Compressed air energy efficiency

All compressed air equipment needs to be replaced at some point, either because it has broken down and can't be repaired or because of a change in business requirements. Purchasing equipment that's energy efficient is usually more expensive, but it's cheaper to run and will save money during its lifetime compared with less efficient models.

Compressed air monitoring before you buy

By installing an effective monitoring system you can get a profile of air demand at your site. This will enable you to buy equipment that matches the demand profile as closely as possible, cutting out the need for compressors to waste energy idling.

Ownership costs of new compressed air equipment

When you choose new equipment you need to consider the overall cost of ownership throughout its lifetime. This includes the purchase cost as well as maintenance, repairs and energy consumption. You may decide to sign up for a manufacturer's fixed-length service contract. This may be for basic maintenance only or an all-inclusive package that covers all parts and labour for routine maintenance, as well as any breakdown or repair costs. The manufacturer will be able to tell you the cost of a service contract for a given period.

Generally, manufacturers can also tell you the energy consumption of a particular piece of equipment under different loads, which you can use to calculate your expected energy costs.

Specification of new compressed air equipment

Every compressed air system installation is unique in its design and purpose. So it's very important that you evaluate your own air demand before you buy any new equipment. When you decide which compressor is most suitable there are several factors to take into account, including:

• the level of air quality that the application or process requires - for example, the compressed air may need to be oil free
• the flow rate and pressure that's required
• how much you have available to spend on the initial purchase and the ongoing running costs

You could consider using a variable speed drive to save energy and money by regulating the output of the compressor.

It's also a good idea to think about adding automatic controls and pressure-regulating devices to your system to further improve energy and system efficiency.