Four reasons to run an ESOS energy audit

By Ruth Fain and Dave Mercer

- Last updated on GMT

Energy audits are not just for energy savings
Energy audits are not just for energy savings

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Energy audits required by the EU’s Energy Savings Opportunity Scheme (ESOS) can help food manufacturers with more than energy savings, explains Golder Associates’ Ruth Fain and Dave Mercer.

From this year, all UK companies with more than 250 employees have to comply with ESOS. The idea behind this is to save thousands of pounds a year, but the benefits don’t stop there. An energy audit can be particularly beneficial for food and beverage manufacturers – and anyone working with perishable goods.

Here are four good reasons why food firms should grasp the ESOS opportunity and review the broader impact of energy use on production: improving product quality, harmonising the energy balance, improving compressed air supply and improving working conditions.

Improving product quality

Energy efficiency can improve overall product quality – particularly for perishable products such as fruit, dairy or fresh meat. To avoid degradation in quality, the entire processing chain must be carefully plotted and controlled. Any break in a cold-chain, for instance, will result in ice cream rapidly melting and becoming crystalline on refreezing. To mitigate the risk of this happening, monitoring and energy efficiency systems should be in place.

At the other end of the temperature scale, we recently audited a factory where a bread-baking oven with dated burner technology and limited turndown capability was leading to over-cooking and less-than-optimal energy performance. This shows that an energy audit can be just as important for ensuring product quality as it can be for saving money.

Harmonising the energy balance

Another benefit of an ESOS audit is regulating the complex energy pathways behind certain food preparation processes. When preparing food and drinks, simultaneous heating and cooling is often required in different parts of the production line.

A good example of taking advantage of this is a poultry processing facility we currently work with. The business captures waste heat from the frozen room ammonia compressors to generate low temperature hot water for other process demands.

Another classic example is breweries recovering waste heat from wort coolers into the liquor stream to heat the next brew.

Such opportunities may take time and experience to identify, but the process of becoming ESOS compliant will help recognise ways in which heating and cooling systems can ‘work for each other’. Obviously, all sites won’t be able to move their freezers and furnaces freely around, and laying pipelines across a whole factory floor is rarely an optimal solution. But we often find that small adjustments can make big differences.

Improving compressed air supply

Compressed air is present in all industrial processes, and usually presents a utility management conundrum. It’s very expensive to generate and distribute compressed air, due to most of the energy input to the compressor being immediately lost as waste heat. Many operators, however, believe that compressed air is free, as it’s ‘just air’. The result is a valuable commodity that is frequently misused.

For a typical food and beverage facility, producers may encounter spiralling costs and staff complaining of inadequate air pressure. In extreme cases, producers may even consider installing additional compressors to compensate for air-related loss of production. If they wait until after they’re ESOS compliant to do this, however, they may realise they don’t need a new air compressor after all.

Improving working conditions

A fourth and vital spin-off of good energy stewardship is staff wellbeing. In an office the link between good lighting, temperature, and staff wellness and productivity is well understood. On a production site, however, the links may not be so obvious. 

A lack of thermal insulation on steam pipework, for instance, not only wastes energy and costs money, it may potentially result in burns and other injuries sustained due to exposure to hot surfaces. And if motors and drives are neglected and fall into disrepair, drive-belts and cooling fans may be exposed, creating excessive noise and unsafe electrical systems.

These are only a few of the advantages that can follow on from an ESOS audit. At Golder we have found that even the newest sites can make considerable financial savings and see an increase in production quality. The ESOS regulation is a good reminder to businesses that they should do what they can to save energy, streamline production and improve their product quality. Given the chance, it will benefit everyone in the long run.

* Ruth Fain is Golder Associates​’ senior environmental scientist and Dave Mercer is energy and carbon lead.

Four reasons to run an ESOS audit

  1. Improving product quality
  2. Harmonising the energy balance
  3. Improving compressed air supply
  4. Improving working conditions

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