Air Compressors – A Guide to Energy Efficiency

Compressed air has been referred to as the fourth utility, along with the first three – water, electric, and gas – because it has become essential as a source of power that is safe, reliable and versatile. It does take a great deal of electricity to compress air; UK industries use more than 20TWh of electricity to compress air, which is about 10% of the industrial sector’s entire energy cost.

It is important to find ways to optimise the energy efficiency of air compression. Not only does it improve the compressor’s performance, it saves on the total cost of ownership.

Cost of ownership can be improved by ensuring that compressors have the correct specifications for the job.

• Is it the right size?
• Is it the best choice for the demand?

There is no need to over-specify because that can call for a higher initial outlay and on-going maintenance that costs more than it needs to.

Know the air pressures and the compressed air flow the system needs. Mid-Tech Engineers and a proper data-logging system can provide the necessary information.

The whole life costs are a consideration. Paying less upfront to save money might not be the best way to go. A cheaper product can cost more in maintenance in the long run.

Energy audits are invaluable. It is estimated that 80% of the total cost of compressor ownership is in the energy costs. If you can track wasted energy and find ways to recover it, it can result in a large cost savings.

An energy audits should include information on ways to improve productivity, how to safeguard product quality and steps to reducing site downtime.

Auditing performance involves assessing pipework leakages, contamination, heat loss, and bad piping. Pipework leakages account for 35% of total air consumption. The leaks can result from shut-off valves and manual condensate valves being left open and leaks in hoses, couplings, pipes, flanges and pipe joints.

Contamination can come from piping that is compromised by unsealed joints, cracked pipes and open valves. Air is allowed to escape while moisture and contaminants enter the system.

Heat loss is a costly waste of energy because 94% of compressor-generated heat can be recovered through having an energy recovery unit fitted to the oil circulation system, or by recirculating warm air. It is also possible to heat water supplies for use in central heating and hot water washing as well as in steam systems.

Poorly laid out or aging piping can create pressure loss, causing the compressor to work harder, using more energy.

In summary, repairing these faults in the system increase the level of efficiency and lower the total cost of ownership. It is wise to be aware of, and open to, initiatives that can identify inefficiencies and help optimise performance, reduce leak reduction and manage air processes.

An example is iConn, which is a cloud-based, air management platform. It can provide advanced analytics that are historic, real-time, predictive and cognitive. It allows issues to be fixed before they become costly problems.

For further information on how Mid-Tech can save your compressed air installation costs on energy usage, please call the experts on 0121 275 2787 or click here.