Excel Compressor Engineering Ltd.

Improved control and maintenance practice not only saves energy costs but can also increase plant life and reduce the risk of costly downtime from compressor failure. These cost savings, while often hard to quantify, can be at least as large as the savings in direct energy costs.

In many cases, more savings can be made where it is economic to recover waste heat and use it for other purposes. Even with the most efficient plant, up to 90% of the input power is lost as heat in the compressor and much of this can be used usefully.

Energy Saving Opportunities

A typical air compressor installation of 100kW (605 cfm) operating on a three-shift seven-day system could cost £40,000/year in energy costs. An approximate cost for compressed air can be calculated assuming a cost of 0.8 p/cfm/hour or £65/cfm/year.

Savings of up to 20% are possible through good selection, control and maintenance, reducing the energy bill in this typical plant by around £8,000/year. This would also reduce CO2 emissions by over 400 tonnes/year.

The Climate Change Levy and Compressed Air

All non-domestic energy users should be aware that on 1st April 2001 the Climate Change Levy came into effect. The CCL applies to electricity, gas, coal and LPG.

The levy on electricity is 0.43p/kWh, so even for small users of compressed air, this could represent a sizable increase in their electricity bill. There will be a rebate of 0.3% on N/I contributions. Some large energy users are negotiating a discount with government for signing up to energy targets. However other companies will pay the full amount and reducing energy use is vital.

How to reduce the impact of the levy

Save tax by taking actions as follows:

Have an Energy Audit carried out;
Identify leaks as the single most important area for saving and carry out corrective action;
Identify opportunities for changing less energy-efficient products in the systems for new energy-efficient products;
Confirm that the piping sizes used are correct in each section of the compressed air system use - size up wherever appropriate;
Study the operation of the system and its compressor and system controls wherever they exist - make a detailed study of the savings to be made with appropriate changes.
By these actions you can not only balance out the levy cost, but you can make substantial savings beyond this.

For more details on the Climate Change Levy call 0800 585 794 or visit www.defra.gov.uk.

Regarding the Enhanced Capital Allowance Scheme, please note the following points:

Two relevant items are covered - electric motors and variable speed drives.
Enhanced Capital Allowances (ECA) can be claimed on qualifying plant and machinery whether the item is bought alone or incorporated into another piece of equipment and whether it is to be used in a new or existing system.
The amount claimable if the qualifying plant and machinery is incorporated into another piece of equipment is the price listed in the web site at www.eca.gov.uk (price includes an amount for installation/fitting).
Items of plant and machinery that pass the qualifying criteria will be found on the web site in November. The qualifying criteria for motors does not distinguish between the applications in which motors may be used. However the qualifying criteria for variable speed drives distinguishes between those used in 'liquid and gas' movement applications and only those VSDs will be entitled to an allowance (ECA).
Seven manufacturers supplied information on Variable Speed Drives as well as the Trade Association GAMBICA. This information was the basis for the prices presented on the web site, a sum was added for fitting/installation.
Examples of prices listed on the web site are as follows:

By fitting an energy-efficient motor you can claim e.g.
11kW motor claim amounts to £1,902;
45kW compressor costs (our list fig.) £13,500 motor claim amount is £5,385 or 39.88%.
The criteria for Combined Heat and Power are fully explained on the web site.