Energy & carbon
Hungary: Old technology, new applications
The brewing process requires a significant amount of heating and cooling at different stages. Many breweries use relatively simple heat recovery processes to capture waste heat from boiling, wort cooling, and other processes but these methods are reaching a point where recovery of heat is uneconomic or impractical to reuse.
Absorption cooling is a very old technology used in refrigerators where electricity was unreliable, costly, or unavailable. They are powered by heat from the combustion of fuel. Waste heat available from a brewery process provides an opportunity to "power" an absorption cooling system.
Czech Republic: Exploring new sources of renewable energy
One of the ways to reduce CO2 emissions is through replacing the current energy supply with greener alternatives. In the Czech Republic, Plzeňský Prazdroj has recently established and completed pilot work at Radegast Brewery Nosovice with a local University to evaluate the feasibility of the anaerobic digestion of waste streams from the brewery process.
From this analysis, it is now possible to compare the life cycle effectiveness of different options of generating renewable energy from waste streams.
Other pathways for producing energy from waste are the direct combustion of spent grain and other solid waste, or the production and recovery of fuel ethanol from these waste streams. The details of these pathways are also under investigation so that the business can make decisions on their most sustainable solutions.
Netherlands: Grolsch - optimising ventilation and lighting systems
Apart from the brewing process itself, ventilation and lighting consume the largest amount of energy at the Grolsch brewery in The Netherlands with its 29 ventilation units and hundreds of lights.
Traditionally, most lighting and ventilation systems ran at fixed times during the day, regardless of whether the plant was in operation or not. Since January 2009, Grolsch has been optimising its control systems to link the ventilation and lighting systems to the operation times of the brewery.
As a result, the brewery has saved more than 100,000 kWh a month without significant capital investment.
South Africa: Cutting out coal
At ABI Phoenix, a feasibility study of a proposed heat recovery system to reduce the load on the coal fired boiler and ideally to completely remove it from service was undertaken. The idea was to recover heat from the ammonia compressors and install an additional heat exchanger on the sugar syrup plant to pre-heat the incoming water with the exiting hot water and simultaneously reduce the amount of cooling required.
From the heat balances it was shown that the recovered heat is not sufficient for all the requirements and an additional make-up supply was required. The proposed solution was to install a heat pump on the roof of the plant and utilise the heat in the exhaust air from the screw compressor to improve its efficiency.
Following this project, the Carbon foot print of the plant has been reduced dramatically; no more coal dust and lower power consumption than before. Coal consumption has been reduced from +- 35 tons per month to zero and power from +- 28 kW to +- 15 kW 24 hour average.
South Africa: Using biogas at Alrode Brewery
At its Alrode brewery in Gauteng, SAB has developed a biogas recovery plant to reduce its traditional dependence on coal.
The brewery’s effluent is treated using an anaerobic digestion process, which generates methane gas. The brewery currently produces five million litres of effluent a day and 90% of the organic load is turned into biogas with a methane content of 85%.
This biogas is used as fuel in a new, dedicated boiler where it’s burnt to boil water and produce steam for the brewing process. This project has provided a further demonstration to the business that using biogas is feasible and could be adopted across other parts of the group.
Reducing our energy and carbon footprint 00:04:17
Reducing our energy and carbon footprint. Why it's a priority and the action we're taking in Hungary and the Czech Republic.