Invest in your system to save money
May 1st 2010

Colum Whelan, Managing Director at C&L Industrial identifies the key areas within a compressed air system where investment can, in most cases,pay for itself through sustainable reductions in energy costs

With economists predicting a "sluggish" recovery in 2010, industry is facing yet another tough year of trading. Alongside continuing rises in electricity prices, tighter budgets will mean that many businesses will be looking for ways to reduce their input and investment costs.

Energy is the most costly part of running a compressed air system, accounting for 75% of the lifecycle costs of the compressed air system. However, compressed air is one technology where most businesses can improve efficiency and in doing so reduce their associated energy costs.

Frequency control Compressed air demand fluctuates depending on shift and production patterns. For some users these fluctuations may be greater in the current economic climate. Investing in a frequency controlled compressor can exactly adapt to demand fluctuations producing the required volume at a constant pressure thus reducing energy costs. The Boge SF series of frequency controlled screw compressors can help to produce savings up to 40%.

In control Introducing a control system that monitors and optimises the compressed air system can assist in reducing energy costs. Designed to continuously adapt to the consumer's momentary demands, Boge's airtelligence PROVIS ensures the most efficient compressor combination is working at all times. A permanent consumption calculation continuously underpins efficient operation of all the interconnected compressors.

Unlike traditional control systems,with airtelligence PROVIS crucial efficiency related parameters are visually displayed.This provides a transparent log of the behaviour of the compressor station and its ongoing efficiency.

Airline system It has been estimated that the leak rate on an unmanaged compressed air distribution system can be as much as 40% of the output.And, just one 3mm leaking hole costing roughly 3kW which equates to some €2400 per annum (depending on your local kW power cost). Additionally, unmanaged air leaks heighten the maintenance required on the associated equipment as unnecessary compressed air is produced.

It is possible to identify air leaks while also assessing the efficiency of your compressed air system yourself.At the end of a working day record the pressure on the air receiver before you turn the compressor off – then start your stop watch.By timing how quick the pressure drops in the receiver you can determine the rate of air leakage in your compressed air system. If your system is efficient, the pressure will remain the same once the compressor has been switched off and in an ideal world it should still be the same when you come to switch on the compressor the next day.However, if the pressure has dropped it is a sure sign that the system is inefficient and that you have air leaks.

Of course, the most comprehensive method is leak detection. By using an ultrasonic leak detector, a compressed air professional can detect and locate the air leaks precisely. Leak detection will often form part of a wider compressed air audit.

You may also want to assess the airline distribution system. Traditional screwed steel pipe can develop an average leakage rate of 10 - 15% in old compressed air systems. Opting for modern aluminium piping can improve flow rates reduce pipe diameter and eliminate leakage.

Heat recovery Almost the entire energy consumption from the supply net of a standard compressor is converted into heat.Taking the example of an oil lubricated screw compressor, up to 94% of the input electrical energy is available for heat recovery.The waste heat generated by the compressor can be redirected into heating spaces, such as workshops, or for pre-heating domestic water. The associated energy costs can therefore be reduced.

The Boge Duotherm heat recovery system can reclaim up to 75% of the electrical power taken into the compressor. This is taken in the form of heat recovered from the compressor oil.

Developed for oil injected screw compressors, these heat exchangers operate independently from the cooling system in a highly efficient manner.

Lubricant choice Opting for a quality long life synthetic lubricant such as Boge Syprem 8000S can yield energy savings of up to 5%. Creating virtually no residual carbon or lacquer deposits, having a stable viscosity, low oil carryover with corrosion as well as wear protection these key characteristics help which make this a highly efficient and energy saving lubricant option.

Maintenance Following the recommended maintenance schedule additionally contributes to the overall energy efficiency of the compressed air system. Eliminating or even reducing service visits will affect the quality of the air produced, the lifetime of wearing parts and the associated energy costs. It is a fact that a poorly maintained compressor will not be working energy efficiently.

Invest to save! Although a number of efficiency remedies can be made at no or low cost (such as repairing air leaks) most of the opportunities will require investment. The good news – most will be self financing in terms of the energy savings they will create.

C&L is the exclusive authorised distributor of Boge compressed air equipment within the Republic of Ireland.

More articles from C & L Industrial Ltd: