Drive addon cuts the cost of compressed air

Edited by the Engineeringtalk editorial team Oct 18, 2006

EnergAir has partnered with KEB to develop an integrated compressor control and management package that is being made available to both end users and compressed air distributors.

Air compressor control specialist EnergAir has partnered with leading inverter drive manufacturer KEB to develop an integrated compressor control and management package that is being made available to both end users and compressed air distributors.

Designed to work with the majority of both new and installed screw compressors, the package offers improved control and management in addition to dramatically reduced energy consumption.

According to Pete Tomlins, EnergAir UK Manager: "Energy saving in compressed air is a massive issue right now; by running even a modest sized compressor house more efficiently companies could reduce their energy bills by tens of thousands of pounds per annum".

"Key to improved efficiency is matching air generation closely with demand and this is difficult to achieve without at least one compressor delivering variable speed operation".

"New variable speed drive (VSD) compressors represent a large capital outlay and most compressors are only part way through their life, hence, a retrofit package at a fraction of the cost makes a lot of sense".

The EnergAir/KEB solution means that end users operating one or more fixed speed air compressor are now able to buy in an optimum energy saving solution without the capital outlay of a completely new VSD air compressor, and ensure that the new variable speed feature will work with virtually any existing installation regardless of age or brand.

Many compressor manufacturers now offer a VSD version alongside their standard fixed speed air compressor range, but these compressors are not delivering the energy savings they should, because in many situations they are not working in unison with other compressors under an effective management control system.

The added advantage of the EnergAir/KEB drive upgrade for existing compressors is that it can easily be integrated into an advanced EnergAir control system designed to help manage and maximise energy savings in multiple compressor installations.

EnergAir and KEB software and hardware engineers have worked closely over the last twelve months to integrate the EnergAir control and compressor management software with the VSD motor control parameters, the task has been made easier by common Modbus communication and a wealth of shared experience.

Says Matt Handley, Managing Director of KEB in the UK: "The KEB drives range spans from 0.37kW through to 800kW and so comfortably covers the usual 50 to 200kW range of most screw type compressors".

"We were also impressed with EnergAir's specialist knowledge of compressor control and excited by the prospect of working on both retrofit and OEM solutions".

Over 60% of KEB's Eur 140 million global turnover is in VSD drives, and so the company is able to offer guaranteed availability and a global supply and support network.

The KEB range of peripheral equipment such as filters and chokes for special requirements and expertise in reducing harmonics also adds to the package of user benefits.

Says Tomlins: "The VSD drive package has been developed partly as a result of market demand and partly because we see a huge opportunity for a convenient and reliable solution".

"Compressed air generation is equivalent to about 10% of industry's total electricity usage, rising to 30% in some sectors".

"By employing an effective drive package such as ours compressed air distributors can also offer end users significant improvements in air generation efficiency".

Payback periods typically range from six to eighteen months depending on the size of the installation and the operating schedule; most large installations tend to run 24h and show shorter payback periods.

To give an example, by installing a VSD retrofit package, and an effective management control system, a site with four 150kW compressors working average shifts could reduce energy usage by over 800,000kWh per annum, reducing annual costs by more than GBP 50,000, based on present energy prices.