Energy Efficiency Measures in the Grocery Industry

Improving energy efficiency through the use of more resource efficient products and services can be a ‘win/win’ in terms of environmental benefits and financial savings for individuals and organisations.

The need for energy efficiency

The food and drink sector is a very energy intensive industry. According to the Carbon Trust, in 2000 the industry used nearly 70TWh of energy, enough to power one million homes for approximately 15 years. As a whole, the food chain is responsible for 17% of the UK’s greenhouse gas emissions (Source: Defra) around 111 million tonnes CO2e, so improving energy efficiency will have an overall positive impact on greenhouse gas emissions.

The financial benefits of improving energy efficiency make it an attractive area for companies to address. Commercial buildings are responsible for approximately 17% of UK energy use, but despite this, the Carbon Trust estimates that businesses in the UK waste some 10-20% of the energy they buy due to poor control of heating, air conditioning and ventilation and through leaving lights and appliances on when not in use.

The Climate Change Agreement

A number of sub-sectors within the food and grocery industry have discussed Climate Change Agreements (CCA) with the UK Government to reduce their energy usage, through the Food and Drink Federation or other trade associations of their own. Agreeing to a CCA enables an 80% discount from the Climate Change Levy. (See Defra link below for more information)

The Carbon Reduction Commitment

The Carbon Reduction Commitment (CRC) will start in 2010, it is a legally binding climate change and energy saving scheme. As a guide organisations spending more than £500,000 a year on electricity will be subject to the CRC. The CRC requires organisations to surrender carbon allowances to cover the emissions they generate, allowances will be available at a fixed price for the first three years, then through an auction. Revenue from the sale of allowances will be returned to obligated companies in proportion to their improvements in energy use. The scheme will be administered by the Environment Agency. Finally CRC is designed with the CCA and EU ETS in mind, it is aimed at organisations outside the scope of both of these ongoing obligations.

Areas of energy usage within the food and grocery sector

Within the food and grocery sector there are a number of specific areas of energy use including:

Refrigeration
Boilers and heat distribution
Cooking
Compressed air
Motors and drives

The following graph shows the relative energy requirements of these technologies:

The percentage of fuel used by technology in the UK food and drink industry

The percentage of fuel used by technology in the UK food and drink industry (Source: Defra)

(Source: Defra)

Refrigeration - The food and drink industry is one of the main users of refrigeration. For many businesses refrigeration costs can account for up to 50% of all electricity used on site (Source: Carbon Trust).

New legislation will mean businesses using refrigerant R22 (an HCFC) in their systems will need to replace them before 2010 when they are due to be phased out under EU regulations on ozone-depleting substances. The potential for large environmental damage from refrigerants is clear: 1 kg of refrigerant R134a has a global warming potential 1,300 times greater than that of 1 kg of CO2, so any small leakage through failure to maintain equipment could reduce the environmental benefits of CO2 energy-efficiency.

Boilers and heat distribution – Uses the vast percentage of fuel consumption within the industry. This is partly due to the fact that almost all of the sub-sectors in the food and drink industry need some form of process heating. There are many ways to reduce energy efficiency through simple measures such as maintenance. The Carbon Trust estimates that a poorly maintained boiler can consume 10% more energy than a well maintained one. Insufficient or ineffective insulation can account for about 10% heat loss in a steam boiler. Ensuring efficient steam generation and distribution can reduce energy costs by up to 50% (Source: Carbon Trust).

Cooking – Within certain sub-sectors of the industry cooking can be the main energy consumer. Energy savings can be achieved through efficient planning and utilising the opportunity for recovery of heat.

Compressed air – Is used throughout the industry for a number of processes from blow moulding plastic bottles to lifting products off conveyor belts to cleaning. It is used because it is a versatile, safe and flexible energy source. However, an unused compressor can still use up to 40% of its full load. A well maintained compressor can be 2% more efficient and with proper understanding of its usage lower pressures can be used to fulfil many requirements.

Understanding the machinery is an essential part of energy reduction and efficiency. If compressors are used with a cool air intake it can improve efficiency, as the air is denser, for every 4°C drop in temperature of intake air efficiency improves by 1%. In addition, up to 90% of the heat generated by the compressor could be ‘captured’ and used for space heating within warehouses (Source: Carbon Trust).

Motors and drives – Electric motors are used in many processes within the food industry. Energy efficiency can be met by ensuring current motors are well maintained and are used at the required speed; lowering the speed of a motor by 20% can produce an energy saving of 50%. Using new motors, such as higher efficiency motors can produce savings of up to 3-4%. The implementation of automatic sensors or encouraging staff to turn off motors that are not in use may also produce significant savings.

Other areas of energy usage

Lighting - Costs can be as much as 40% of a building’s electricity consumption. The correct use of lighting controls to reflect actual occupation and daylight linking can reduce operating costs by between 25% and 50% (Source: Energy Services and Technology Association).

Cooling - Mitsubishi Electric estimates that air conditioning (AC) units could account for up to 1,600,000 tonnes of CO2 emissions per annum for cooling. This figure could increase to 2,400,000 tonnes of CO2 per annum by 2016. From January 2009 all existing AC systems over 250 kW must have been inspected. A further two-year leeway has been negotiated for smaller AC systems (Source: ENERGY).

Meeting the target and regulations

The food and grocery industry must reduce CO2 emissions by 20% between 1990 and 2010 to meet the targets set out in the Governments Energy White Paper 2007. Emission rates from food manufacturers fell by 15.2% from 1990 to 2005, according to data from the Digest of United Kingdom Energy Statistics. The major contribution to this fall has been a move from coal to gas in power generation, in addition to improving energy-efficiency. This puts the industry in a good position to hit their targets for 2010.

However, to reach the targets of 60% reduction in emissions by 2050 there is likely to be a need for change in attitudes regarding energy efficiency and investment in alternative and new technologies with cooperation between government and businesses regarding planning permission. (See Renewable energy through micro-generation factsheet)