Industrial Energy Efficiency Accelerator - Guide to the brewing sector pot

The investigation centred on the brewhouse, small pack packaging, kegging/casking and clean-in-place CIP as the key areas where significant improvements could be made, and opportunities

Industrial Energy Efficiency

Accelerator - Guide to the brewing sector

They UK produces 49 Mhl per year and emits approximately

446,000tCO2/yr Current CCA data shows that in the UK there are 14 large breweries or packaging sites (over 1Mhl per annum), a further 35 smaller breweries and circa 700 micro-brewers This Sector Guide

describes the IEEA findings for the UK brewing sector The investigation centred on the brewhouse, small pack packaging, kegging/casking and clean-in-place (CIP) as the key areas where significant improvements could be made.

Executive Summary

The Carbon Trust has worked with a range of industry sectors as part of its Industrial Energy Efficiency

Accelerator (IEEA), to identify where step-change reductions in energy use can be achieved through detailed investigation of sector-specific production processes The IEEA aims to support industry-wide process carbon emissions reduction by accelerating innovation in processes, product strategy and the uptake of low carbon technologies, substantiated by process performance data and detailed process analysis

This Sector Guide describes the IEEA findings for the UK brewing sector The investigation centred on the brewhouse, small pack packaging, kegging/casking and clean-in-place (CIP) as the key areas where significant improvements could be made, and opportunities categorised according to their degree of technical/commercial maturity; that is, their relative ease of implementation and cost-effectiveness:

Wave 1: Energy efficiency best practice and process optimisation: On the basis of the best practice

survey carried out as part of the investigation, we estimate that a 5% carbon saving (22,000tCO2/year) could

be made across the sector, from the consistent application of all feasible best practice opportunities

Furthermore, a large number of process optimisation opportunities were identified, relating to the kettle, pack pasteurisation, keg/cask processing, and CIP Those that were possible to quantify show that a further 9% reduction (40,000tCO2/year) in carbon emissions could be achieved by optimising and implementing existing best practice process technologies

small-Wave 2: Opportunities on the horizon: Some newer technologies have the potential to make step-change

reductions in energy use; these are commercially available but UK take-up has been low due to concerns over quality impacts, lack of capital, and longer than acceptable payback periods Areas of potential are: adding a wort stripping column or direct steam injection to the kettle; kettle vapour heat recovery; using a heat pump to recover energy from refrigeration system condensers; and switching to flash pasteurisation or cold sterile

filtration for small-pack pasteurisation An estimated 12% further carbon reduction (54,000tCO2/year) could be achieved from such measures

Wave 3: The future: A number of game-changing technologies have been identified but will require both a

time and financial commitment from the industry to bring them to technical and commercial fruition We estimate the key areas with potential to be UV pasteurisation for both kegs and small pack, as well as the development of more precise techniques for monitoring and controlling CIP processes We estimate that a further 5% carbon saving (22,000tCO2/year) could be made across the sector from these measures

The cumulative impact of these opportunities, illustrated in the “carbon reduction road map” shown in the figure below, shows that a total sector carbon saving of 31% is achievable, equivalent to 138,000tCO2/yr on sector baseline emissions of 446,000tCO2/yr This is based on a sequenced scenario where all Wave 1 opportunities are implemented first, so that the impact of the more innovative opportunities of Waves 2 and 3 is made against

an already reduced baseline carbon emissions level

The table below summarises the main areas of opportunity categorised according to the three-wave approach described above, along with their sector-wide carbon saving potential Note that the measures are not necessarily additive; for example, a wort-stripping column and direct steam injection are alternative boil-off reduction

technologies, and cannot both be applied Furthermore, the sector saving potential is also affected by previous improvements: for example, if best practice and the optimisation of existing processes has first been carried out, then the incremental benefit of, say, cold sterile filtration will be against an already reduced starting position of energy use and carbon emissions The road map graph above has taken these factors into account

Wave

Sector Carbon Saving Payback Average

(years)

(tCO 2 ) (%)

1 Best practice in energy Implement all feasible opportunities 22,300 5.0% Unknown

1 Process optimisation Reduce boil-off 11,200 2.5% Unknown

1 Process optimisation Increase high gravity dilution 11,900 2.7% Unknown

1 Process optimisation Optimise tunnel pasteurisers 14,000 3.1% Unknown

1 Process optimisation Optimising cask washing 3,100 0.7% 5.9

Wave

Sector Carbon Saving Payback Average

(years)

(tCO 2 ) (%)

2 Small pack pasteurisation Flash pasteurisation with clean room 53,400 12.0% 2.5

2 Small pack pasteurisation Cold sterile filtration 68,600 15.4% 6.3

2 Pasteurisation Heat pump on refrigeration condenser 29,200 6.5% 2.7

2 Kegs/Casks One way containers Dependent on transport distance

3 CIP Real-time cleaning verification 4,600 1.0% Unknown

3 CIP CIP – novel technologies and low

temperature detergents (ECA) 7,500 1.7% Unknown

3 Small pack pasteurisation UV pasteurisation for small pack 68,300 15.3% 6.5

3 Kegs/Casks UV pasteurisation for kegs 13,100 2.9% 1.9

Recommendations

We recommend that the brewing industry takes the following, tiered approach to energy and carbon efficiency improvement:

Implement remaining best practice techniques and technologies: investigation has shown a considerable

potential for sector-wide savings by ensuring the consistent application of sustained best practice

management techniques and available technologies

Optimise existing processes in the brewhouse, packaging and CIP: further, low cost savings can be

achieved through improvements to operating practices and production methods and by refinements to existing process technologies

Collaborate with equipment suppliers on technology trials and pilot projects: to assess the potential

impact of less proven technologies and techniques on product quality and to support the progression to effective equipment design

cost-BBPA and Carbon Trust support: should be sustained to ensure that the UK brewing sector has access to

the information, case studies, partnerships and innovation support funding that will enable it to achieve the significant carbon emissions reduction potential identified as part of this IEEA project

Table of contents

Executive Summary 1

1 Introduction 6

1.1 Sector background 6

1.2 Process operations and energy 7

1.3 Sector carbon emissions 15

1.4 Issues and barriers relating to energy efficiency and change 16

1.5 Focus processes 17

1.6 Regulatory drivers 18

1.7 Other business drivers 20

1.8 Industry progress on energy saving 20

2 Methodology for monitoring and analysis 21

2.1 What metering/data gathering was done and why 21

2.2 The kettle 21

2.3 Small pack pasteurisation 21

2.4 Keg/cask processing 22

2.5 CIP 22

2.6 Engagement with the sector 22

2.7 Participating host sites 22

2.8 Data gathering 23

2.9 Metering approach 23

2.10 Best practice checklist 24

3 Key findings: best practice survey 25

4 Key findings and opportunities: the kettle - wort stabilisation 27

4.1 Key differences between the sites investigated 27

4.2 Data to support analysis 28

4.3 Best practice process optimisation opportunities 35

4.4 Innovative wort stabilisation opportunities 37

4.5 Summary of findings 40

4.6 Barriers to implementation 40

5 Key findings and opportunities: small pack pasteurisation 41

5.1 Process description 41

5.2 Data analysis and modelling 43

5.3 Process optimisation opportunities 47

5.4 Innovative opportunities and significant change 50

5.5 Summary of findings 53

5.6 Barriers to implementation 54

6 Key findings and opportunities: keg and cask processing 55

6.1 Keg processing 55

6.2 Cask processing 59

6.3 Summary of findings 62

6.4 Barriers to implementation 62

7 Key findings and opportunities: clean-in-place 64

7.1 Data analysis 64

7.2 Process optimisation opportunities 66

7.3 Innovative opportunities 67

7.4 Summary of findings 69

7.5 Barriers to implementation 70

8 Summary of opportunities 72

8.1 Overview 72

8.2 General best practice energy efficiency opportunities 73

8.3 Process optimisation opportunities 73

8.4 Innovative opportunities 73

9 Sector roadmap and next steps for the UK brewery sector 78

9.1 The step change roadmap 78

9.2 Elements of the roadmap 79

9.3 Next steps for the UK brewery sector 81

Appendix 1: Metering rationale 84

Appendix 2: Good practice checklist 87

Appendix 3: Kettle technologies and business cases 99

Appendix 4: Small pack technologies and business cases 104

Appendix 5: Keg/cask technologies and business cases 112

Appendix 6: CIP technologies and business cases 115

1 Introduction

Beer has been a staple part of British food since the early 12th century; it is a much-loved part of British culture, and the industry supports around 400,000 jobs, as well as sustaining many other UK businesses The British Beer and Pub Association (BBPA) is the leading trade organisation representing the UK beer and pub sector Its members account for 96% of beer brewed in the UK and own more than half of Britain's 53,000 pubs

Until the 16th century beer was brewed in the home, on farms, in wayside taverns and, later, in the great

monasteries Its commercial mass production is estimated to have started in the early 16th century; with records

of production available from 1750 They show that UK beer production peaked in 1979 at 67.5 million hectolitres (Mhl) but since then the production has declined gradually to its current level of less than 49 Mhl per year These declines are synchronous to the changes in consumption trends There have been marked declines following recessions at the beginning of 1980s and 1990s, the decline in heavy industry and, more recently, following consumer trends towards wine and other drinks

Figure 1 UK beer consumption and production (1960-2009)1

1 Source: BBPA

Against the background of declining production, there has been a rationalisation within the industry The earliest record of number of breweries is in 1690, which shows around 48,000 breweries in existence at that time In the past thirty years, the number of industrial breweries has reduced from 140 to 49; however the number of micro-breweries has gone up in this period Current CCA2 data shows that in the UK there are 14 large breweries or packaging sites (over 1Mhl per annum), a further 35 smaller breweries, and circa 700 micro-brewers Heineken

UK (formerly known as Scottish & Newcastle), is the market leader, with more than a quarter of UK beer sales The next three largest companies are also foreign-owned companies; Molson Coors UK; AB-InBev UK; and Carlsberg UK On the other hand, Irish-based Diageo is famous for its Guinness brand and is a major

multinational3

There are some changing trends in beer consumption that are worth noting Data from the BBPA CCA 2010 report shows that the volume of ale and stout, the traditional British beers, has been slowly replaced by lager, changing the proportion of ale and stout to lager from 99:1 to 25:75 over the last 50 years Climate Change Agreement (CCA) data for the brewery sector shows that the majority of exclusive ale producers are relatively small in size (annual production below 1 Mhl), whilst all the exclusive lager producers fall in the large category (annual production greater than 1 Mhl)

There has also been a shift from drinking in pubs, clubs and bars to taking beer home for consumption home sales now account for 47% of the total sales volume as against 10% in the 1970s Change in the

Take-packaging mix is consistent with the growth in take-home sales; the percentage of returnable bottles, kegs and casks is steadily declining matched by the percentage of non-returnable bottles and cans increasing The volume sold in cans has doubled in the last 30 years.4

From the perspective of energy and water consumption, the UK brewing industry has seen some encouraging trends Even though, for lager, lower fermentation temperatures and cold-conditioning periods result in higher requirements for refrigeration and thus electricity consumption, and specific energy consumption (SEC) in manufacturing is higher for small-pack products, BBPA data shows that the overall SEC for the industry has fallen by 53% since 1976 Overall water consumption has declined by 49% over the past 30 years and total carbon emission for the industry has dropped by 55% from its 1990 level These achievements are discussed in detail further in this report

1.2 Process operations and energy

1.2.1 Process overview

Brewing is the production of alcoholic beverage through fermentation Brewing specifically refers to the process

of steeping, and extraction (chemical mixing process), usually through heat The brewing process uses malted barley and/or cereals, un-malted grains and/or sugar/corn syrups (adjuncts), hops, water, and yeast to produce beer Brewing has a very long history, and archaeological evidence suggests that this technique was used in ancient Egypt Descriptions of various beer recipes can be found in Sumerian writings, some of the oldest known writing of any sort

Most brewers in the UK use malted barley as their principal raw material The main ingredient for the brewery process (barley grain) goes through malting process (this process is usually done in a dedicated maltings facility separate to the brewery)

2 Climate Change Agreements between industry trade associations and the Government allow industry members to claim an 80% discount on the Climate Change Levy In return companies must hit energy/carbon saving targets and report on progress

3

Source: BBPA

4 Source: BBPA

First the grain is steeped in water This prompts germination which generates α-amylase and β-amylase among other enzymes These enzymes are used later to help the starch in the grain be broken down to sugar Before the malted grain is delivered to the brewery it is usually roasted or dried in a kiln, with longer roasting periods resulting in a darker and stronger tasting beer

1 The first step in brewing involves milling the malted grain to increase the surface areas available so that

a high yield of extracted substances can be obtained This is either done wet or dry

2 The crushed malt (grist) is then mixed with heated water in the mash tun (a large vessel) During

mashing natural enzymes within the malt break down much of the starch into sugars which play a vital part in the fermentation process This process usually involves the mash being heated to several specific temperatures (break points) and resting at these temperatures where different enzymes break down the starch into the desired mix of sugars The sugar and starch solution that is created in the process is called the wort Before the mash is filtered the temperature is raised to 75ºC to deactivate enzymes

3 To separate out the wort from the grist the mash is either sent through a lauter tun or mash filter

o A lauter tun is a large vessel up to several meters wide and tall which has a slotted bottom (like a giant sieve), which allows the wort to fall through while retaining the spent grain grist behind To extract any remaining available sugars fresh water is sprayed onto the mash after the initial wort has drained through the slotted base (sparging)

o A mash filter is comprised of a series of plates where the mash is compressed to remove as much wort as possible The remaining mash is sparged but less water is needed as the mash filter provides a larger cross section of mash with less depth to penetrate than in a lauter tun

o In some cases the lauter tun is combined with the mash tun to form a mash vessel In this case, the wort run off is directed through a series of slotted plates at the bottom of the tun The mash floats

on top of the wort This tends to be the slowest wort separation system although it is the lowest cost

in terms of capital outlay

4 The next step involves the wort being heated in a wort copper or kettle; wort stabilisation involves the

boiling and evaporation of the wort (about a 4-8% evaporation rate) over a 1 to 1.5 hour period The boil

is a strong rolling boil and is the most energy-intensive step of the beer production process

The boiling sterilises the wort, coagulates grain protein, stops enzyme activity, drives off volatile

compounds, causes metal ions, tannin substances and lipids to form insoluble complexes, extracts soluble substances from hops and cultivates colour and flavour During this stage hops, which extract bitter resins and essential oils, can be added Hops can be fully or partially replaced by hop extracts, which reduce boiling time and remove the need to extract hops from the boiled wort If hops are used, they can be removed after boiling with different filtering devices in a process called hop straining

5 In order to remove the hot break or trub (denatured proteins that form a solid residue), the boiled wort is

clarified through sedimentation, filtration, centrifugation or whirlpool (being passed through a whirlpool tank) Whirlpool vessels are most common in the UK

6 After clarification, the cleared hopped wort is cooled Heat exchangers for cooling are of two types:

single-stage (chilled water only) or multiple-stage (ambient water and glycol) Wort enters the heat exchanger at approximately 96-99ºC and exits cooled to pitching temperature Pitching temperatures vary depending on the type of beer being produced Pitching temperature for lagers run between 6-15°C, whilst for ales are higher at 12-25°C Certain brewers aerate the wort before cooling to drive off undesirable volatile organic compounds A secondary cold clarification step is used in some breweries

to settle out trub, an insoluble protein precipitate, present in the wort obtained during cooling

7 Once the wort is cooled, it is oxygenated and blended with yeast on its way to the fermentation vessel

During fermentation, the yeast metabolizes the fermentable sugars in the wort to produce alcohol and carbon dioxide (CO2) The process also generates significant heat that must be dissipated in order to avoid damaging the yeast Fermenters are cooled by coils or cooling jackets In a closed fermenter, CO2 can be recovered and later reused Fermentation time will vary from a few days for ales to closer

to 10 days for lagers The rate is dependent on the yeast strain, fermentation parameters and the taste profile that the brewer is targeting

8 At the conclusion of the fermentation process the beer is cooled to stop the action of the yeast, then the

yeast is removed through settling or through a centrifuge (although with real ale: some yeast is retained and after the ageing it is added with the beer into the barrel)

9 Beer aging, conditioning or maturation is the final production step The beer is cooled and stored in

order to settle remaining yeast and other precipitates and to allow the beer to mature and stabilize Different brewers age their beer at different temperatures, partially dependent on the desired taste profile Beer is held at conditioning temperature (-1ºC to 10ºC) for several days to over a month, and then chill-proofed and filtered (the process for real ale is different to lager as the yeast is not filtered out

of the beer)

10 With the beer at a temperature of -1ºC, a kieselguhr (diatomaceous earth or mud) filter is typically used

to remove any precipitated protein and prevent the beer from clouding when served at a cool

temperature With real ale the beer is not filtered so that the yeast is still ‟live‟ when it goes out in the cask

11 In high gravity brewing (high alcohol content), specially treated de-aerated water is added after the

filtration stage to achieve the desired final gravity The beer‟s CO2 content can also be trimmed with CO2 that was collected during fermentation or from external supplies if enough CO2 is not recovered

on site

12 After being blended the beer is then sent to the bright (i.e filtered) beer tanks before packaging

13 Beer that is destined for bottles or cans is sent to the fillers where a vacuum or counter pressure filler

will be used to fill the bottles or cans Other beer will go to the flash pasteuriser and be filled at a later stage in, casks, kegs or sometimes directly into tankers (for real ale the beer is not pasteurised as this would kill the yeast)

14 The beer must be cleaned of spoiling bacteria to lengthen its shelf life One method to achieve this,

especially for beer that is expected to have a long shelf life, is pasteurisation, where the beer is heated

to 75°C to destroy biological contaminants (this is not carried out with real ale as the process would kill the yeast in the beer) Different pasteurisation techniques are tunnel or flash pasteurisation:

o Flash pasteurisation involves the beer being heated for a short amount of time and then being bought down in temperature in a heat exchanger prior to filling

o In-pack pasteurisation is the pasteurisation of beer that has already been packed in bottles or cans,

by bringing the whole packed beer container up to temperature by heating with hot water This is typically done in a tunnel pasteuriser

15 Finally, the packaged beer undergoes any secondary or retail packing processes and is ready to be

shipped

The diagram below shows these 15 process steps, with annotation as to where cold liquor (cold water), hot liquor (hot water) and de-aerated water are added and where heating and cooling take place

Figure 2 Brewing process diagram

1.2.2 Process energy use

Energy consumption in any typical brewery is divided into two parts: electrical energy consumption and thermal energy consumption Thermal energy or heat is typically generated using different fuels in a boiler house Coal and oil were the traditional boiler fuels but the majority of boilers in the UK now run on natural gas, with fuel oil used as a backup Process heating typically accounts for a large share of thermal energy Electrical energy is either sourced from grid or generated on-site, for example, in a combined heat and power (CHP) system Refrigeration for process cooling typically accounts for a significant amount of electricity An estimated CO2 emission breakdown by main process areas in percent of total energy consumption is shown in Figure 3 for a typical brewery

Brewhouse 38%

Packaging 35%

Cold Block 11%

Waste Water

7%

Building services 5%

Warehouse 4%

Typical site CO2 breakdown

From this information the main energy users can be identified as the brewhouse, packaging and the cold block By looking at data gathered during previous studies at several large breweries (2+ Mhl/year) we have

been able to build an approximate model of where both electrical and thermal energy is consumed in these individual sections of the brewery

The following diagrams and charts demonstrate what type of inputs each process requires and how much energy each stage consumes In each stage the areas that we have focused on may not be broken down into exactly the same stages that the process diagram indicates This is down to insufficient metering for each process

5 Source: Camco data and IEEA data collection

As the charts below indicate, the vast majority of thermal energy is used in brewing operations and pasteurisation, while electricity consumption is more evenly divided among fermentation, beer conditioning and utilities

In Figure 5 below, the wort cooler has been combined with the whirlpool and kettle as a single energy user The wort cooler also recovers a lot of heat as hot liquor (water) which is subsequently used to mash in the next batch, therefore the virgin energy consumed for mashing is not as much as might be imagined as the energy recovered

by the wort cooler reduces the energy input required for mashing in

The largest energy consumer in this area is clearly the kettle and any energy improvements in this area could have a significant impact to overall brewery SEC (Specific Energy Consumption measured in this report as kWh/hl)

Cold Block

In Figure 7 below, the centrifuge has been combined with the fermenters, and the beer cooler has been combined with the filtration process

From the data available the electrical energy used in fermentation and filtration are the highest users in this area and involve multiple processes (maturation involves cooling tanks only) The thermal inputs to filtration and fermentation are down to the local clean-in-place (CIP) systems The filters use a considerable amount of hot caustic solution to regenerate

Packaging

Figure 8: Packaging process diagram

In Figure 3 the packaging block is shown to be responsible for the second highest energy demand within the brewery, but how this energy is used cannot be simply mapped out by individual processes as each brewery operates a different packaging set up and pack type mix

Packaging in the UK is comprised mostly of non-returnable bottles and cans, and returnable kegs and casks Table 1 shows the percentage of beer packed in each of these pack types

Table 1 UK packaged beer by packaging type

Pack Type Percentage of Packed

1.3 Sector carbon emissions

1.3.1 Carbon dioxide emissions

In the UK in 2009, 43 Mhl of beer was produced, and 49 Mhl of beer was packed, by the 49 sites covered by the sector‟s CCA (ie, 6 Mhl was imported in bulk but packaged in the UK) From these sites a total of 446,000 tonnes

of energy-related carbon dioxide (tCO2) was created, either through electricity or direct fuel consumption on site From CCA data this gives average specific energy consumption (delivered) of 37.5 kWh/hl and emissions of 10.4 kgCO2/hl

1.3.2 Brewery archetypes

We plotted a scatter graph of the 49 sites included in the BBPA CCA of production versus specific delivered energy per hectolitre of beer produced, and specific CO2/hl of beer produced This allowed us to draw a line of best fit or performance curve through where the sites lay on the graph By combining this line with a production dividing line (1 Mhl/year production was close to the average and also a sensible division between smaller and larger sites); the graph is divided up into four sections, or “archetypes”:

Large sites with higher Specific CO2 (kgCO2/hl product)

Large sites with lower Specific CO2

Small sites with higher Specific CO2

Small sites with lower Specific CO2

Figure 9 CCA brewery archetypes: total CO2 ratio vs total production with 90% of sites falling between the grey lines

Table 2 CCA brewery archetypes

Number

of sites

Production (hl)

UK production (%)

Carbon emissions (tCO 2 e)

UK-wide emissions (%)

We can draw the following conclusions from this analysis:

The 14 largest sites account for 83% of the volume of beer packaged and 75% of the total sector carbon

emissions;

Small sites with a high SEC are the next most significant group accounting for 10% of volume and 17% of sector carbon emissions;

In general, larger sites have a lower SEC; and

Implementing emissions reduction projects in larger sites has the greatest potential to reduce sector

emissions

1.4 Issues and barriers relating to energy efficiency and change

Of the 49 brewery sites in the UK under the sector‟s CCA, 14 account for 83% of all beer produced and 75% of sector emissions These 14 large breweries are solely lager or mixed breweries and replicability of opportunities within these sites will lead to the highest source of emissions reductions within the sector

However, a large amount of beer is brewed under license in the UK, with many of these sites owned by multinational companies based outside the UK, producing the same brand in many locations around the world, as well as similar beers under different brand names, depending on location and market Hence, the need to seek agreement from internationally based head offices for changes of UK based plants creates a significant barrier to change

A potential barrier to energy and carbon emission saving opportunities that may affect the recipe of beers or fundamental packaging methodologies (e.g reductions in kettle boil-off or different pasteurisation techniques) could understandably be the manufacturing standards used by non-UK companies that apply to multiple breweries around the world

If significant energy saving opportunities can be identified without any negative impact on beer quality or taste, then the key to enabling these opportunities for the UK industry may be the effective engagement of such international stakeholders These companies are all committed to reducing their environmental impact across each market they operate in

1.4.2 Heritage and tradition

Many UK brewers rely on brands that claim to have been brewed in the same way for long periods of time This builds a brand that the consumer can associate with and trust to deliver quality with a recognisable taste Encouraging any changes to the brewing process to save energy could be met with opposition if these changes might impact on marketability, and any such changes would need to be measured in terms of the impact on

quality and taste The customer is king and many breweries perceive that their customers have great loyalty to their beer being produced in the traditional way in the traditional place

This should not deter this project from investigating opportunities that could lead to large emissions reductions, but it demonstrates that the Carbon Trust and its partners must engage sensitively with brewing companies to examine how to mitigate any issues that may arise in this area

Initial site visits have shown that, on the whole, sites are aware of what is termed „best practice‟ for energy efficiency However, this does not mean that all best practice opportunities have been carried out where possible Where best practice has not been carried out, it is usually down to lack of available capital, resources or expertise or the barriers discussed above

By sending out a best practice survey to the whole sector we aimed to understand the level of remaining best practice implementation potential, including the key opportunities still outstanding for the sector and the main reasons they have not already been implemented (see Section 3 for the summary of the best practice survey results)

The UK brewery sector is made up of three main types of site: large lager and mixed breweries; small ale-only breweries; and micro-breweries that do not participate in the CCA The way in which each type of brewery makes beer is similar, but the technology used can be very different

While looking for opportunities for this project care has been taken to include areas of focus that have an effect

on all parties involved This has been carried out to reduce the likelihood of disenfranchisement and maximise the potential benefits of having the whole sector involved

Through choosing the following processes to focus on we aimed to direct the project into the investigation of the highest energy using processes with the potential for improvement, as discussed and agreed in initial sector stakeholder meetings

Kettle As shown in Figures 3 and 5, the kettle is the biggest energy user on site, so we have looked into

how much energy is required to boil several different types of beer By looking at multiple breweries we have been able to see what effect different kettle technologies have on the energy demand of the brewery process and have used this information for building business cases for alternative approaches

Small pack pasteurisation The second biggest area of energy use in the brewery is in packaging Within

this area the pasteurisation of the beer is the largest user of heat and a considerable user of water and electricity We have monitored two distinctive types of small pack pasteurisation:

o Flash, where the beer is heated up to pasteurisation temperature and then brought back down in a

plate pack heat exchanger and then bottled; and

o Tunnel, where the beer is bottled or canned and then raised in temperature by spraying hot water

over the containers to bring the whole package up to pasteurisation temperature

Currently, the use of flash pasteurisation is relatively rare in the UK due to a number of perceived product quality issues By looking at these two types of pasteurisation we have been able to build a case study of the two systems, showing the cost involved with each and the implications for moving from one technology to the other This has also been used to quantify savings from using alternative pasteurisation techniques such

as ultra-violet light

Kegging and casking The third area that we have focused on is in kegging and casking After our initial

site visits we identified that the way in which kegs are cleaned was different at each site and there was no common approach The monitoring programme aimed to understand what the different heat loads within the keg cleaning process are and recorded exactly how much water, electricity and compressed air is used to process each keg at different sites By calculating these utilities benchmarks we assessed the potential savings from alternative technologies in both the keg cleaning and flash pasteurisation for kegging

Cask cleaning has been largely been ignored over recent years as the ale industry has been in decline against lager Resurgence in ale from the cask means that this area needed to be revisited and so we have tried to understand how much energy is used in cleaning a cask and to define standards for current best practice

Technical difficulties acquiring data from kegging plants during the analysis period resulted in the data being limited to electrical, heating and water demands for two of the sites monitored The compressed air recorded was not reliable and so has not been included in the analysis

The implication of the decline in casking means that we were unable to find no real innovative technologies

in the market place

Clean in Place (CIP) within breweries is a significant energy and water consumer Camco carried out an

extensive analysis of CIP as part of the Dairy Sector IEEA project It is believed that much of this information and knowledge is transferable to the brewing sector, therefore metering of CIP was not carried out under the scope of this project Where data already exists we have sought to establish benchmarks of key parameters for comparison

1.6 Regulatory drivers

Climate Change Agreement

The UK brewery sector is covered by a Climate Change Agreement, under which its members receive an 80% (65% from April 2011) discount on the Climate Change Levy, which is a surcharge on energy bills The CCA requires companies to reduce their carbon emissions according to an agreed series of milestone targets or risk losing the discount The scheme provides an incentive to improve energy efficiency: if the milestone reduction target is not achieved, the CCL discount is lost on all eligible energy and fuels purchased As a consequence, the brewery sector has performed well, reducing energy consumption by 16% since the start of the scheme in 2001.6 The brewing sector has met its final targets, resulting in the discount being received up to March 2013 The Government has recently announced that Climate Change Agreements will continue until 2023, albeit with a reduction in the discount from 80% to 65% up to April 2013

EU Emissions Trading Scheme

The EU ETS is an emissions reduction framework based on the cap-and-trade principle First implemented in

2005 across the EU, it covers selected energy intensive industries such as cement and steel production, as well

as all combustion plant above a certain size threshold (20MW) If a site meets one of these criteria then it must join the EU ETS, even if it is also covered by a CCA Sites in the EU ETS are assigned an emissions “cap” and they must buy emissions permits to hit the cap if they are not able to reduce their emissions internally Large brewery processing sites are covered by the EU ETS on the basis of their boiler plant, which typically will be above the size threshold

Phase 3 of the EU ETS runs from 2013 to 2020

6 Source: BBPA

F-Gas Regulations

HFC refrigerants are affected by EU Regulation 842/2006 which covers certain fluorinated greenhouse gases Gases) commonly used in refrigeration equipment HFCs are potent greenhouse gases, with global warming potential of around 2,000 times that of CO2 In the past, refrigeration and air-conditioning systems have leaked potent HFCs into the environment Some brewery sites use separate refrigeration plants with HFCs for areas such as cold storage

(F-The F-Gas regulations require operators of air-conditioning and refrigeration plant to prevent refrigerant leakage and carry out regular leak tests; recover HFC refrigerants during maintenance and plant decommissioning; maintain accurate records and ensure that equipment is appropriately labelled and operated and maintained by suitably trained personnel

Ozone depleting substance regulations (R22 phase out)

The phase out of HCFCs for maintenance of existing refrigeration and air-conditioning systems began at the end

of 2009, as required by EU Regulation 2037/2000 on ozone-depleting substances The regulation banned the use of virgin HCFCs for maintenance from the end of 2009 and recycled fluid from the end of 2014 This is of crucial importance for many companies and means that all users of R22 and other HCFC systems, if they have not already, need to consider alternative refrigerants or the purchase of new equipment Other clauses in the regulation also affect the use of existing HCFC systems

It is important that R22 users have plans in place for the phase out of HCFCs as it is not recommended to rely on the 2014 recycled fluid phase-out date, as this date could be brought forward as part of the review process The amount of fluid being recycled has in fact turned out to be very small to date, so there is no guarantee that sufficient supplies of recycled R22 will be available between 2011 and 2014

An alternative in some refrigeration plant is to use drop in replacement gases, but in nearly all cases these have

a degrading effect on refrigeration plant energy efficiency

IPPC

Integrated Pollution Prevention and Control (IPPC) has been in place since 2005 and is a regulatory system that employs an integrated approach to control the environmental impacts of certain industrial activities It involves determining the appropriate controls for industry to protect the environment through a single permitting process This UK Guidance for delivering the PPC (IPPC) Regulations in this sector is based on the Best Available

Techniques (BAT) reference document BREF produced by the European Commission7 For the brewery industry the relevant reference document is (BREF 08.2006) Food, Drink and Milk Industries The key environmental issues managed by the permitting system are:

1.7 Other business drivers

Brewery processing is energy and water intensive and the introduction of carbon-related costs as well as rising utility prices means there is ongoing pressure to reduce utility usage This is compounded by the squeeze on product sales prices applied by the major customers – supermarkets – who are in a position to dominate the supply chain and who often require their suppliers to take the pain of product discounts and promotions in the stores Cost minimisation is a powerful driver

Another driver is corporate responsibility where, in addition to meeting any regulatory requirements, a brewery company wishes to demonstrate to investors, environmental organisations, the local community and the wider public its commitment to being proactive on climate change: for example, by setting voluntary carbon reduction targets; producing product carbon footprints; or investing in environmental initiatives which reduce energy use and carbon emissions

1.8 Industry progress on energy saving

Beer brewing and processing into consumable products is complex and energy intensive The internal and external pressures on the industry to reduce costs have led to the brewery sector being progressive in terms of energy efficiency This in turn means that good practice in energy management is already quite widespread (although there is still potential for improvement, as described in Section 3), and that many of the cost-effective technology opportunities for reducing energy consumption – such as improved controls, or more efficient motors and drives - have already been implemented at some sites The good practice survey (Section 3) shows that there are still significant opportunities available, and perhaps the best way to address this is to raise awareness

of what is possible at a site level

2 Methodology for monitoring and analysis

2.1 What metering/data gathering was done and why

The monitoring design and associated data gathering carried out as part of this project concentrated on the first three of the four focus areas described in Section 1.5 The objective of the monitoring exercise was to deploy additional meters to supplement the information that could be collected from the existing sites‟ SCADA systems

to build up a more detailed understanding of the following process energy consumptions:

The kettle/wort copper

Small pack pasteurisation

Keg/cask processing

Virtually all breweries in the UK have these processes as part of their facilities, meaning the opportunities

identified in these areas will have the widest possible potential for replication across the UK brewing industry (for further details, see the metering rationale in Appendix 1)

2.2 The kettle

For the kettle we wanted to understand how much energy is used to process the wort For each type of beer, a target % boil-off or evaporation is predetermined and then the wort is heated for a time period to produce this reduction We measured the energy going into the kettle and the level of wort in the kettle during the boiling process to determine how efficiently this energy was used to achieve the required evaporation

With data from three different wort heating systems (three different breweries), we were able to approximate the potential savings to be made through using alternative technologies That is, by understanding the relationships between boil-off and energy consumption for different kettle types, we were able to quantify the benefits from technologies that claim to reduce evaporation energy requirements

2.3 Small pack pasteurisation

The heat energy used in small pack pasteurisation is used to raise the temperature of the beer up to a set level

so that pasteurisation can occur We measured the heating energy, electrical energy for pumping and water consumed over a period of time then divided it by the bottle count on a bi-daily basis to get a specific metric for tunnel pasteurising systems

We did not meter a canning line as there were more systems running bottle pasteurisers in the sites that we visited than canning lines, so bottle pasteurisers were targeted

2.4 Keg/cask processing

To look at how energy savings could be made with kegs and casks we first needed to know how much energy is used in keg and cask processing For casks, the process varies from site to site and so we compiled a list of five different sites showing how much heat, water and - where possible - electrical energy and compressed air is used

to process each cask From this list we were able to identify the key differences and best practices available, to determine the savings that could theoretically be made if all cask sites moved to that option

This process was also carried out for kegs Both of these figures were then used to work out the emissions savings associated with alternative packaging technologies

CIP was not specifically metered during the monitoring process since much CIP monitoring had been done under the IEEA dairy sector project However one ale production site did have comprehensive data available for heat and water input to CIP Lessons from the dairy sector IEEA project were applied to existing CIP data provided by the brewing sector project partners In the dairy sector IEEA project, the heat input for CIP detergent tanks in several systems was measured over a two week period at two dairies This heat input was then divided by production over this period to give a specific heat consumption figure based on production Although this figure was obtained for a different industry, dairy processing plants and breweries share common CIP problems, both sending fluids through multiple tanks and processes which have to be cleaned to a high level

Although the cleaning requirements for milk and beer are different owing to the differing viscosities and chemical properties the nature of CIP systems and their operational parameters are similar in both industries in that both run caustic and acid cleaning solutions, at similar temperatures to lines and vessels The notable difference for the brewing industry is that a lot of hot water product pushes and line flushes are used between batches and optimisation represents a significant area for water and subsequently heat savings

This dairy analysis will be used in conjunction with available brewery energy data to gain an understanding on CIP costs and produce some indicative figures for energy saving opportunities Relevant technologies have been analysed and potential energy savings and project costings have been carried out where the available data permits

During the study there was continual engagement with the sector laying out the progress with the investigations and the direction that we were intending to follow This was initially done through agreement with the five

companies providing sites for metering, agreeing which site would be the most suitable, and then through regular update emails, project steering group meetings and a final workshop, in which a wider industry group (including technology companies, equipment suppliers and academics) participated in a discussion on the benefits and barriers relating to the opportunities identified

2.7 Participating host sites

Five companies volunteered five sites as hosts for the IEEA Stage 1 project investigation Out of these sites there are three large sites with lower SEC, one large site with higher SEC and one small site with higher SEC This group is therefore representative of archetypes that represent 93% of sector volume and carbon emissions

When choosing the most suitable sites to work with there were a number of considerations to take into account

By working with larger sites the opportunities highlighted can be rolled out over the largest proportion of the market (in terms of beer production volume and emissions) But working with smaller sites can often prove fruitful

as small organisations are often much more free to implement and trial new technologies than larger companies Selecting two sites with similar production volumes, but different SECs allowed us to compare directly the effects that different innovative technologies may have on energy consumption at higher and lower energy intensity sites

From these five sites, three were selected for additional metering in order to give a clearer picture of the energy consumption in the focus areas and the potential for savings through the adoption of new and innovative

technologies The information already available from the site SCADA systems for the other two sites was deemed adequate, allowing the data gathering budget to be used in the most efficient manner

2.8 Data gathering

Data on process energy performance was gathered in the following ways:

Historical CCA data from UK breweries;

Meetings with site engineers over the course of the metering programme;

Data collected during the metering programme itself; and

An energy good practice check list that was sent out to industry members

2.9 Metering approach

Having focused the metering strategy on the kettle, small pack pasteurisation, keg and cask processing, a monitoring plan was devised to collect process performance data whilst minimising disruption to the day-to-day running of the site The approach involved looking at the individual processes that needed to be understood in more detail, highlighting the data needed to build this picture

The first step was to assess the range of information already being recorded on the sites‟ SCADA systems, to identify data gaps and to specify the data collection hardware to be installed in order to build up a complete set of data The appropriate metering technology was then specified and installed by the Carbon Trust‟s IEEA meter data services contractor and either connected to the sites‟ SCADA system or operated independently of site systems, with the data from both sources combined for analysis after the end of the monitoring period

Ease of metering

Collecting identical data sets from the target sites was not possible, as the data that could be extracted from the SCADA systems, or the variables to be metered, varied from site to site, depending on the age and installation of the systems Older SCADA systems have limited memory and so the number of variables that were monitored in such cases was limited, reducing the amount of data that could be combined with any additional metering for analysis

Typical metering devices installed at the three sites:

Steam meters

Cold and hot water flow meters

Compressed air flow meters

Temperature sensors

Pressure sensors

Level sensors

Electricity meters

Data Integrity

The metering devices were installed between December 2010 to February 2011 and data collection from new metering came online in a phased manner from early February through to early March The target minimum data collection duration was a two-week period, since brewery operations normally run 24/7 with little variation and a representative data set should be achieved over that period

Through data collected from all of these sources process energy models were compiled that enabled the review

of energy consumption during the monitoring period and the identification of any irregularities during process runs

It should be noted, that at the time of writing, not all data had been analysed due to various operational delays relating to meter installation, therefore the breadth and depth of the data set, whilst representative, is not as comprehensive as originally planned Where any assumptions have had to be made as a result of this we have indicated them clearly

2.10 Best practice checklist

During the project a survey of energy best practice in energy efficiency was sent to industry members The aim of this survey was to gain an understanding of how widespread the take-up of good practice was across the

industry, and also to raise awareness of energy related issues and the IEEA programme itself The survey comprised a checklist of around 150 questions, divided into the following sections:

Compressed air

Building and lighting

Cooling and refrigeration

Boilers and steam distribution

Vacuum

Waste water treatment

Process energy

Energy management practices

Whilst best practice is not directly in the scope of the IEEA project this exercise allows companies to benchmark themselves against the industry and drive forward best practice, and allows us to highlight potential areas for improvement later in this report

The results of the IEEA investigations are shown in the following sections:

Section 3: summary results from the best practice survey

Section 4: key findings for the kettle process

Section 5: key findings for small pack pasteurisation

Section 6: key findings for keg and cask processing

Section 7: key findings for clean-in-place

Whilst Section 8 provides a summary of innovative energy saving opportunities relating to these process areas and Section 9 some recommendations on next steps for the sector

3 Key findings: best practice survey

The pie chart below illustrates how, for the 10 companies that responded to the survey, a quarter of the

measures classed as „best practice‟ have not yet been carried out, but could still be implemented There could be good remaining potential for energy savings within the industry simply based on the implementation of further low, or no-cost measures Whilst this is not the focus of the IEEA programme, energy managers within the industry should make sure that they have not overlooked any of these measures that may apply to their sites The full analysis of survey responses from the 10 different sites (all separate companies) is shown in Appendix 2, which also provides the full list of best practice measures

Figure 10 Summary of responses from the best practice survey

Some examples of the reasons that were chosen for „not possible‟ responses were:

Payback deemed too long

Not relevant to our specific processes / operation

Impact on production downtime

Lack of people skills

Lack of available capital budget

Process change control restricted to group level

From the collated responses there were several opportunities that half or more of the respondents thought were possible, and were either easy to implement or could lead to substantial savings These opportunities included, for example:

Installing a flue gas economiser to use the waste heat from the boiler flue gas for preheating the boiler feed water saving between 4 – 6 % on annual fuel bills

Improving boiler burner efficiency through oxygen trim with flue gas analysis (2-3% fuel savings for out of spec burners)

Install VSDs on air compressors

Whilst the survey provides a useful indication, the true value of such opportunities will only be assessable on a site-by-site basis, through more detailed analysis of the relevant process area

4 Key findings and opportunities: the kettle - wort stabilisation

Stabilising wort through boiling in the kettle has been a largely unchanged process for the last few hundred years

in the brewing industry Only recently has this process been challenged and the real underlying process

requirements identified which affect the flavour and quality of the wort

In summary, the main aims of the boiling process are:

Isomerisation of hops (unless using pre-isomerised hops)

Sterilisation of the wort

Removal of volatile compounds

Boiling sterilises the wort to stop spoilage during fermentation, breaks down the hops, and the gas bubbles formed during boiling help strip the wort of unwanted volatile compounds This process is very energy intensive due to the large amount of heat going into the system to evaporate the wort to the prescribed level (boil-off)

4.1 Key differences between the sites investigated

The gravity at which the beer was brewed varied from no final dilution to up to 49% final gravity dilution Brewing

at higher gravity, and blending after the kettle or fermentation stage, reduces the amount of wort that needs to be boiled and hence energy consumption When beer is brewed with a 49% end dilution only 51% of the final packaged beer needs to pass through the kettle, roughly halving the required energy necessary

Vapour heat recovery

Vapour heat recovery for the kettle was found on one of the host sites The technology involves passing the vapour from the kettle boil-off and condensing it through a vapour condenser where the heat is extracted to a hot water tank storage tank This hot water is then used for a pre-heater to increase the temperature of wort entering the kettle This technology typically works well with high percentage boil-off sites, since there is more vapour produced and hence more energy to capture Therefore the lower the boil-off the lower the financial return on investment for such a system and it is not typically viable for boil-offs below 4%

For the IEEA site where there was vapour heat recovery, the size of the system was actually quite small and was primarily designed to remove odour from the vapour that drifted to the local town rather than to recover a

significant amount of energy

Internal / external calandria

Wort heating is carried out through passing the wort through a heat exchanger known as a calandria The

calandria can either be placed externally, outside the kettle, or placed in the centre of the kettle The advantage

of an external type is that it can be easily inspected for maintenance but there is an efficiency advantage for the internal variety as all of the heat exchanger is emerged in the wort, reducing heat losses as well as reducing pumping needs

Heat source – steam or high pressure hot water

The calandrias (kettle heat exchangers) at the IEEA sites monitored were supplied with steam or high pressure hot water (HPHW, 140ºC) Steam systems are more common and typically easier to maintain than HPHW systems, but there are no flash steam losses from trapping and condensate recovery in a HPHW system, which theoretically makes them more energy efficient Flash losses are explained in the pasteurisation section of this report (Section 5)

4.2 Data analysis

The diagram below shows a simplified wort kettle and shows the four variables that were recorded to support the analysis of the specific energy used on each brew:

Wort input temperature

Temperature of wort in the kettle

Fill level

Heat input

Figure 11 Simplified kettle diagram

Heat in, temp

Fill level Temp

of wort

The variables have been plotted for a single boil in Figure 12 below to demonstrate a boil profile This particular kettle uses a dynamic boiling system where the wort is heated under pressure and then the kettle depressurised causing vigorous boiling and flashing At first, a consistent heat input can be seen which raises the wort

temperature to boiling point When the temperature gets to around 100ºC a number of sequential heat inputs can

be seen through the evaporation phase, where the level of the wort starts to reduce until 3.5% of the wort has been evaporated A traditional kettle shows a similar profile, but with a more consistent heat input

The total energy input over the duration of the boil has been used to work out the specific energy per hectolitre of beer processed

Figure 12 Kettle level, temperature of the wort in the kettle and heat input for a brew at Site 1

0 100 200 300 400 500 600 700

Kettle level, kettle temperature and heat input over one brew for a standard

product at one brewery

Heat input into kettle (kW) Temperature of wort in kettle (C) Level of kettle (hl)

4.2.1 Kettle energy balance

Based on a mixture of monitored and calculated data, we have derived a loss bridge for the kettle heat input The following diagrams shows loss bridges (energy balances) for the boiling process at two of the monitored

breweries Delays in metering installation resulted in monitored data for the third site not being available in time for this report

Figure 13 below shows that is a 4% unaccounted for loss in the kettle, with the remaining energy being roughly split 50:50 between heating up the wort to boiling point, and evaporating the necessary amount to achieve the required boil-off level Figure 14 shows a 3.5% under-measurement which is most likely due to the steam meters not reading true

Overall however there is a good correlation between the calculated and empirical data, suggesting that it is credible for us to estimate the specific energy for other sites based on calculation from their boil-off percentage and other kettle parameters

Figure 13 Loss Bridge for the kettle process in Site 1

Figure 144 Loss Bridge for the kettle process in Site 3

The other important fact when looking at the energy used per specific volume of packed beer is the high gravity (HG) dilution rate This is the percentage of fresh water that is added after the wort has been boiled in the kettle This can be before fermentation or prior to filling

All of the beer brewed in the IEEA host sites visited boiled-off some fraction of their wort in the kettle; however, the energy per hl needed to raise the wort temperature to boiling point will be similar across these sites The differentiating variables are the amount of wort that is boiled-off and the end dilution rate A beer with 50% HG dilution rate will only need half the heat energy per packed volume to a beer with a 0% HG dilution rate Figure 15 shows the boil-off and HG dilution of the main products at three of the IEEA host sites monitored Both of these parameters have an effect on the overall specific energy consumption for packaged beer, as shown in Figure 16

Figure 15 Specific heat breakdown of the kettle at three breweries

Figure 16 shows that the higher the brewed gravity (the HG dilution rate) and the lower the boil-off, the lower the specific energy per unit of packed product The losses associated with the kettle have been shown to have up to

a minimal effect on the specific energy consumption (4% maximum, shown in Figure 13) and so the important factors remain boil-off and HG dilution How both of these factors affect the specific energy is discussed in Section 0 below

Figure 16 Specific heat from boiling in packaged beer

0.001.002.003.004.005.006.007.00

4.2.2 Specific heat energy per boil

To calculate the energy needed for a boil we take the input temperature into the kettle and calculate the energy needed to bring the wort to boil For the theoretical boil-off for that product we can calculate the energy needed to evaporate the liquid from the wort These two figures were then compared to the energy actually used in the plant

as steam or high temperature hot water

The results shown in Figure 17 show that the amount of energy used for boiling the wort of the main product at a modern brewery is approximately 5.3 kWh/hl (average for the main product at one site over a month) The variance demonstrated for one product is explained below in Section 4.2.3

Figure 17: Specific energy recorded for wort heating of one product at one site over a month

The range for other products over the same period was from 4kWh/hl to 8kWh/h with the majority of the brews having specific energy consumptions between 5 and 6kWh/hl The high gravity dilution rate at which the beer shown in Figure 17 was brewed was 49%, so the overall specific energy for the wort stabilisation process,

5.3 kWh/hl

allowing for dilution, is around 2.6kWh/hl of packaged product This is for a brewery that has an average boil-off

in the kettle of 3.6%

The more energy intensive breweries that we visited for this project had boil-offs of around 7% with a high gravity dilution rate of 10% and so the specific energy per hectolitre of packaged product relating to wort

stabilisation/dilution would be higher at 7.8kWh/hl

This demonstrates the energy saving potential of high gravity brewing, where this is allowed by site conditions and the product requirements

The key variables we expect to lead to energy input variances between boils are laid out below For each case

we have compared two of the breweries where in-depth data was available to show our rationale for quantifying the difference in how the kettles are controlled:

Wort input temperature – was measured to be consistent at the two breweries analysed Both consistently show a variation in kettle entry temperature of only 2ºC (between 75ºC and 77ºC) This was consistent

across a broad range of products

Figure 18: Wort entry temperature per brew for multiple products at one brewery

The volume of the batch – the two monitored sites showed variable kettle volumes, usually due to the kettle being topped up with fresh process water to correct any wort strength inconsistencies

Figure 19: Maximum fill level for the kettle per brew for one product over a month for two sites

0 100 200 300 400 500 600 700 800

Heat losses from the system – should remain consistent for the same kettle, boiling the same product over

As can be seen from Figure 20 there is a significant variation in specific energy for evaporation input per brew of +/-50% from the average specific heat energy As evaporation accounts for approximately half of the energy going into the kettle (the other half is for pre- heating), this gives a total energy variance of up to +/-25% per brew

Figure 20 Specific energy recorded for wort heating of one product at one site over a month for a site with timed boils

Because the rate of heat input and boil time are constant the specific energy of the boil varies according to other inconsistencies such as brew volume For example, if the boil was based around the actual volume of beer starting in the kettle the energy delivered would be on a quantified basis

The second brewery monitored controlled its kettle based on calorific input (heat energy input level as a function

of product volume and desired boil-off), rather than timed controls (boiling the wort for a fixed time and then testing for volatile removal level) The variance in specific energy for one product using a calorific controlled boil over a month is shown in Figure 21 below The amount of energy input per hectolitre of product is visibly much more consistent

Note that the different average specific energy shown in Figures 20 and 21 are not material here, since kettle configuration and boil-of level vary between the two sites The relevant finding is that a calorific (or specific heat input) controlled boil gives a more consistent specific energy compared to time control, and offers a potential energy saving through the avoidance of over provision of heat

Figure 21: Specific energy recorded for wort heating of one product at one site over a month for a site with heat input controlled boils

3.1 3.12 3.14 3.16 3.18 3.2

Number of brews in a month of one product

Another possible cause of the inconsistency seen in Figure 20 could be burn-on, which reduces the efficiency of the calandria (fouling) However the kettles monitored were both cleaned weekly and if there had been burn-on then within each week a consistent pattern of increasing energy consumption would have been seen, which it was not As we did not have alternative data to identify the burn-on status of the kettle we cannot make any further judgements on this possible variable, but it seems unlikely from the data collected

For the site that has a varying heat input (Figure 20), the boils with the least specific energy are currently deemed acceptable, inferring that the boils with higher specific energy are using more energy than is necessary It is therefore reasonable to assume that moving to a system that operates on calorific controlled boils will reduce the variance in heat input, and result in an overall reduction in energy consumption though the avoidance of over provision of heat

If a kettle with a timed boil-off could be re-programmed to provide heat on a calorific controlled approach, then the amount of energy needed for evaporation could potentially be reduced by as much as 25% from the average for a site where the boil off is around 3.5% For sites with a higher boil (say 7% boil off) the fraction of total kettle energy needed for evaporation will be higher at 64% as more energy is needed to drive off more wort compared

to the pre-heat energy, so the potential saving by moving from a time-based to calorific controlled boil-off will be greater

4.3 Best practice process optimisation opportunities

There are several methods in which the energy necessary to carry out these processes can be reduced All of the following opportunities have been carried out in one form or another by international brewers and have been proven to work without detrimental effects to the quality of the beer We recommend that if any of these

opportunities have not yet been implemented then they should be investigated; their savings potential has been estimated in Section 4.3.2 below.

Calorific kettle heating: As described above, controlling the heat input to the kettle based on specific energy

per hectolitre of wort in the kettle allows for more accurate control of kettle energy input and process

consistency For the specific example identified during the monitoring exercise, if the kettle with the timed boil-off had been re-programmed to provide heat on a volume based or specific calorific approach, then the amount of energy used for evaporation could potentially be reduced by as much as 30% from the average As

the loss bridges in Figure 13 and Error! Reference source not found show, as about half of the energy

used in the kettle is used for boiling, the equivalent energy reduction for a site could be between; equivalent

to around 10% of total site energy usage (this saving will ultimately depend on the level of boil-off in the kettle which depends on product type and whether high gravity brewing is used)

Reducing boil-off and using a sparge ring: The processes needed to stabilise the wort are heating and

volatile stripping The heat can be provided by heating the wort to 99.9ºC as boiling does not increase the temperature for sterilisation or hop isomerisation The stripping of volatiles can then be performed through sparging air or another stripping gas through the wort instead of relying on the steam bubbles generated through a boil This can be done in conjunction with boiling, gradually reducing the boil and increasing gas sparging while controlling the product characteristics in line with the recipe requirements This concept differs from the opportunities discussed in Section 4.3.2 regarding reduced boil-off, as it uses air as the stripping gas rather than steam

Low pressure boiling: The have been a number of systems introduced to the market which use a vacuum

pump to lower the static pressure on the kettle and reduce the boiling temperature to extract volatiles from the wort while reducing the total energy needed for the process Evaporation rates as low as 2.6% have been cited using this technology This will give similar savings to the direct steam injection savings quantified below (2.5% equivalent boil-off)

Vapour heat recovery: The technology involves passing the vapour from the kettle boil-off and condensing it

through a vapour condenser where the heat is extracted to a hot water tank storage tanks This hot water is then used for a pre-heater to increase the temperature of wort entering the kettle This technology typically works well with high percentage boil-off sites since there is more vapour and so more energy to capture Therefore the lower the boil-off, the lower the financial return on investment for such a system and it is not typically viable for boil-offs below 4%

Isomerised hops: The use of pre-isomerised hops allows the boil-off of the wort to be reduced as the

process of breaking down the hops has already been completed prior to insertion into the kettle As one of the key reasons for boiling the wort is to isomerise the hops this allows the amount of energy needed for the boil

to be reduced There will still be some energy needed (outside the brewery) to pre-isomerise the hops, but this will be only to heat a small volume of liquid to boiling point, with no evaporation needed, so there will be a net reduction in energy use

Reduction in steam pressure: Through reducing the steam pressure that is delivered to the calandria the

burn-on of wort onto the heat exchanger (calandria) will be reduced and the efficiency of the heat exchangers increased This will also result in a reduction in CIP as the amount of burnt-on material adhered to the heat exchanger will be less, saving further energy and water The flash steam losses in the condensate system will

also be reduced (explained in detail in the pasteuriser section of Section Error! Reference source not found.) The penalty to pay for reducing steam pressure is an effective de-rating of heat exchanger capacity Adding adjunct after the kettle: If adjunct is needed then it should be added on the hot side of the wort

cooler This will save on the energy needed to boil-off the fraction on the adjunct added since the adjunct material will not need heating The reduction in kettle energy consumption is in proportion to the reduction of liquid volume in the kettle

4.3.2 Impact on the UK brewing sector

Due to the variations in brewing techniques across companies, sites and product types it is difficult to estimate with any accuracy the overall impact potential of the above measures across the UK brewing sector The

following opportunities have been quantified using data from the monitored sites to act as a baseline for the current industry position

From the monitoring and analysis carried out on the data collected on kettle energy use we have shown that the energy used can be accurately modelled to within 7 % in terms of specific energy consumption (see loss bridges

in Figure 13 and Error! Reference source not found.) The figures below demonstrate the effect of changing

the key wort stabilisation variables and give an indication of the potential savings available for these changes

Reduction in boil-off: For every 1% that boil-off can be reduced in the kettle, the specific energy needed to

boil the wort can be reduced by 0.63 kWh/hl, which results from less energy being used for the latent heat of evaporation, through evaporating 1% less of the total beer volume For a gas-fired 2Mhl per year brewery this works out as approximately 1.85p/hl reduction in the heat costs or a total site energy cost reduction of

£37,000 per annum If we assume that ale brewers use an average boil-off of 7.5% and that the bigger lager and mixed brewers have an average boil off of 5%, bringing the entire sector down to a common baseline boil-off of 3.5% would yield a sector carbon emissions reduction of around 2.5% Through this reduction in heating fuel, the equivalent average carbon emissions reduction per site would be 337tCO2 per year, for a notional 2Mhl site

Increase in high gravity brewing: For a kettle where the input temperature is 75ºC and there is a 3.5%

boil-off (similar to one of the breweries monitored as part of this project), we have looked into what difference a change in the final gravity dilution of the beer will have on specific kettle energy consumption Through increasing the final gravity dilution less wort has to be processed (heated and evaporated) in the kettle for the same amount of beer packaged

Across the sector, it appears that lager brewers already have reasonably high HG dilution rates of 35% to 50% The ale brewers we spoke to appear to have lower rates, on the order of 10%, and the biggest opportunity for change exists here However, if the large breweries were able to make a further incremental increase in HG rate then a significant impact could be made across the sector

For every 10% increase in the final gravity dilution of the beer at an ale brewery the specific kettle energy can be reduced by 0.73 kWh/hl If we extrapolate an increase from 10% HG dilution to 50% HG dilution this equates to a sector carbon saving of approximately 1.4% (just for the smaller, mostly ale-producing sites)

For a 2Mhl brewery this equates to a £31,000 annual energy cost saving and an annual carbon reduction of 275 tCO2 If the brewery had a higher boil-off of around 7% (similar to the higher boil-off brewery that we monitored), this saving would be 0.73 kWh/hl, with a total annual site energy cost saving of £44,000 and annual carbon reductions of 390 tCO2

If the same were carried out for the larger breweries, by moving from an average HG dilution of 42% at the larger sites monitored to 50% HG dilution, the savings would be 5,800 tCO2 across the UK, equivalent to a further 1.3% sector carbon saving That is, the total sector potential from increased levels of high gravity brewing could lead to

a total sector carbon saving of around 2.7%

4.4 Innovative wort stabilisation opportunities

We have investigated a number of innovative opportunity areas with the potential to reduce kettle energy

significantly:

Using a stripping column

Using a steam injection atomiser

Continuous brewing

Sequential mashing

These are described below; further details on the first two opportunities are described in Appendix 3, together with their outline business cases Insufficient data was available to quantify the savings and hence provide business cases for continuous brewing and sequential mashing

Wort stripping column: The concept involves applying alternative wort boiling technology that offers major

energy savings while producing very high quality wort, and so improving final beer quality The technology also assures an efficient and flexible elimination of unwanted volatile compounds in the wort (such as DMS – dimethyl sulphides)

The device is placed "in line" between the wort cooler and the settling tank and sends the wort through a packed bed, with steam sent up through the bed in the opposite direction This packed bed increases the surface area of the wort, while subjecting the liquid to high temperature steam, ensuring that volatiles can be removed effectively

With a maximum evaporation rate of 2% claimed by manufactures the amount of energy used in the wort boiling process is dramatically reduced, especially for the breweries that currently operate at higher boil-off Note that energy is still needed to pre-heat the wort

Figure 22 Illustration of where a stripping column would sit in the wort processing line

Wort steam injection: The technology is a specifically designed steam injection system that produces very

effective mixing through promoting a supersonic shock wave in the mixing zone The wort is atomised and the mixture of high surface area and the high temperature of the steam allow for elevated removal of volatiles and unwanted flavours from the beer Through removing these compounds faster the total amount of energy needed in the boil is reduced This technology can be retrofitted to existing wort coppers and takes the place

of heat exchanger based calandrias

Up to 50% energy reduction in comparison to using calandria based technology is cited by manufacturer with

no burn-on of material as there is no heat exchange surface This technology also requires energy to pre-heat the wort, so the savings relate to the reduction in evaporation energy

Other innovative opportunities

Below are more innovative opportunities to do with the wort stabilisation process where, due to their early

developmental stage, it has not been possible to develop outline business cases

Continuous brewing: Continuous brewing involves sending the wort through from the grist stage through to

the filling process in one continuous process At present beer production is a batch process, where each batch is limited to the size of the vessel in which it is being processed

Sequential mashing: Sequential mashing involves sending the mash down through multiple vessels while

transferring the wort from vessel to vessel in the opposite direction This process involves increasing the extract potential of the wort, using less water, therefore using less energy to heat the mash to the temperature required for enzyme reactions to take place

The effect of on the energy needed to carry out the wort stabilisation process on both of the brewery types investigated is shown in the graph of Figure 23 below We compare the existing baselines to the technologies and improvements that have the potential to deliver the largest reductions, for both a low and high boil-off

brewery archetype using supplier data Many of the optimisation opportunities would improve site energy

performance to somewhere in between these two extremes These figures take both boil-off and final gravity dilution into account to calculate the specific heat requirements for final packaged beer

Direct steam injection into the wort has been carried out in the UK but all of the previous examples of wort stripping columns to reduce evaporation have been carried out outside the UK in Russia, Belgium, China and Peru to name a few locations

Figure 23 Wort kettle: innovative opportunities

Figure 23 shows the effect the first two innovative opportunities have on the energy used at a brewery Clearly the opportunity for saving is greater at sites with higher boil-off rates Implementing these opportunities could result in a sector-wide CO2 saving of between 4.2% for the wort steam reactor, and 4.8% for the wort stripping column assuming a 50:50 split of more modern breweries with low boil-off rates, and older, less energy-efficient breweries

The payback period for these opportunities depends on the boil-off rate at the brewery Those that operate their kettles with a boil-off of less than 4%, as well as brewing at high gravity, will find it difficult justify the adoption of these technologies However the payback at the other end of the spectrum is more favourable, with breweries operating an 8% boil-off with final gravity brewing (0% final high gravity dilution) yielding a payback of less than

three and a half years These paybacks should improve as the technologies become more mainstream and unit

Sector Carbon Saving (tCO 2 pa)

Sector Carbon Saving (%)

Average Site Cost Saving (£)

CAPEX (£)

Average Payback (years)

Kettle Reduce boil-off 100% 11,200 2.52% £56,000 Unknown Unknown Kettle Increase high

gravity dilution 100% 11,900 2.66% £60,000 Unknown Unknown Kettle Wort stripping

Kettle Wort steam

injection 100% 18,700 4.2% £130,000 £420,000 3.2

4.6 Barriers to implementation

Changing traditional brewing methods: Tradition has been a very strong influence in how beer is made

with many sites taking pride in producing beer in a similar manor for many years Opportunities that involve

changing this tried and tested method raise concerns that the reputation for consistency may be damaged,

leading to loss of confidence in the brand

Scalability of small-scale test results: Brewers may agree that beer made with new technology on a pilot

scale tastes just as good, or even better at times but confidence is lacking that this can then be produced on

an industrial scale with sufficiently mitigated risks, as there may be no reasonable way to go back

Available capital: Lack of available capital resources has been cited as a reason why breweries do not take

up utility saving technologies For example, modernising a brewhouse or replacing packaging equipment

could be a multimillion pound investment which may not be justifiable on utility savings alone