Firms make huge savings through energy efficiency

30-Apr-2010 - Last updated on 13-Mar-2017 at 14:42 GMT

Companies could save themselves large amounts of cash by the systematic monitoring and targeting of their use of utilities, which can lead them to becoming far more energy efficient, it has emerged.

For example, as part of its 2007 'Purple Goes Green' commitment to halve carbon dioxide emissions by 2020, Cadbury has following an audit reduced carbon emissions at its Chirk factory in North Wales by well over 100t by reducing compressed air leaks on equipment.

An air leakage audit carried out by industrial maintenance specialist Brammer identified leaks on machinery that were costing Cadbury more than £32,000 a year. These were repaired at a cost of just £1,500 less than 5% of the leakage cost identified.

In the future, Cadbury will use a computer-aided web-based leakage management system, which will report on and provide data on where leaks are occurring.

For most manufacturers, compressed air represents more than 10% of total energy bills, claims Brammer. As well as being the most expensive form of energy a company uses, compressed air machinery can have a leakage rate of up to 2030%, it added.

Cadbury's environmental manager Matt Bardell said: "The compressed air solution specification is much more efficient than our previous set-up and we're really starting to see a healthy reduction in our energy consumption as a result."

Meanwhile, Dairy Crest has reduced gas consumption at its Kirkby factory which makes branded spreads, such as Utterly Butterly, Clover and Vitalite by 18% following an energy audit carried out by Spirax Sarco. This identified the need for a number of energy-saving measures, such as a range of steam system improvements.

Steam system optimisation played a big role in achieving the overall savings, leading to rapid payback on the costs of the audit. "In terms of payback we're talking months, not years," said Dairy Crest's engineering manager Gordon Davies.

One of the big improvements was achieved by raising the temperature in the boiler feed tank from between 79°C and 82°C to 96°C. Generally, claimed Spirax Sarco, increasing the temperature of the feed to a boiler by 6°C reduces the boiler's energy consumption by 1%, so this measure alone will have yielded savings of at least 2%.

Condensate recovery was another area that produced big results, raising the proportion of hot, treated water recycled back to the boiler from 76% to between 94 and 95%.

In addition, the steam system audit highlighted a variety of other energy saving measures, such as repairing and installing insulation, improving the blow-down control on the boiler and repairing or replacing any malfunctioning steam traps.