Industrial Energy Efficiency Accelerator - Guide to the brewing sector

127 Pages·2011·3.36 MB·English

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, small-
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.
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
Brewing Sector Guide 2

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.

Step change road map for UK brewery sector

100%
90% 14%
80% 12%

70%
100% 5%
60%
50%
40% 69%
30%
20%
10%
0%

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.

Sector Carbon
Average
Wave Saving
Area Description Payback
(1/2/3)
(tCO) (%) (years)
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
Brewing Sector Guide 3

Sector Carbon
Average
Wave Saving
Area Description Payback
(1/2/3)
(tCO) (%) (years)
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 Kettle Wort stripping column 21,500 4.8% 2.4
2 Kettle Wort steam injection 18,700 4.2% 3.2
2 Kegs/Casks One way containers Dependent on transport distance
3 CIP Real-time cleaning verification 4,600 1.0% Unknown
CIP – novel technologies and low
3 CIP 7,500 1.7% Unknown
temperature detergents (ECA)
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 cost-
effective equipment design.
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.
Brewing Sector Guide 4

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
Brewing Sector Guide 5

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
Brewing Sector Guide 6

1 Introduction

1.1 Sector background
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
Brewing Sector Guide 7

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. Take-
home sales now account for 47% of the total sales volume as against 10% in the 1970s. Change in the
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
Brewing Sector Guide 8

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.
Brewing Sector Guide 9

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.
Brewing Sector Guide 10

Figure 2 Brewing process diagram