Heating and Ventilating

Cool-Therm has installed a pair of Turbomiser chillers into an unusual application in Wales
In what is believed to be the first cooling project of its kind in the UK, two Turbomiser chillers are cooling high power lasers and clean rooms at Photronics' production facility in South Wales.

The project, which involves two model TMA300 Turbomiser chillers each rated at 300kW, was carried out by specialist cooling contractor Cool-Therm (Wales).
The Turbocor-based chillers replaced aging Trane and Climate units running on R22 and the interim refrigerant R79.

Photronics makes components for semiconductors and flat panel displays. It has nine manufacturing plants around the world, strategically located near the major electronics and display screen producers.

The chillers provide chilled water to clean room air handling units and vital cooling for manufacturing lasers which cut masks and reticles - very fine optical etchings - for high quality imaging screens.

It is the first of the manufacturer's facilities to make the switch from conventional cooling technology to the new generation of high efficiency chillers based on compact, inverter-driven centrifugal compressors.

The new compressors are oil-less and have a drive shaft that runs on levitating magnetic bearings.

A key requirement was that the replacement chillers had to operate with very low noise levels and deliver high efficiency, reliable cooling.

'Another important consideration in the project was managing the switch over from existing to new chillers,' says Cool-Therm's Dave Blackmore. 'Photronics operates a 24/7 continuous process business, and there had to be continuity of cooling during the change-over and high resilience once up and running.'

This required meticulous planning by Cool-Therm engineers throughout the installation and commissioning process. The use of oil-less Turbocor compressors is a major advantage in such a situation, as there is no need to wait for the traditional 24-hour crank case pre-heat operation to boil off oil before switching into circuit.'

Dave Blackmore says: 'The Turbomiser is highly flexible in this respect, and lends itself well to 'running switchovers' when the manufacturing process cannot be interrupted.

'The installation was carried out at ground level and was completed without too many complications. There was a requirement to adjust the water flow during the change over process in order to balance and optimise performance. This was accomplished by updating the pipe work and valve configuration.'

The switch over was achieved smoothly, on schedule, ensuring that the laser manufacturing process continued uninterrupted.

Electricity consumption by plant at the site was carefully monitored before and after the installation. Since the Turbomisers were installed, the end user reports that energy used for cooling has been halved.

With a fairly constant process load throughout the year energy savings are expected to be significant and expect to provide a pay-back on the project in around 17 months.

Patrick Silman, who heads up the process facilities at Photronics, said: 'We are monitoring energy use carefully and are on schedule to save some £170,000 within two years on power costs alone, a very impressive achievement and exactly what Cool-Therm promised they would deliver.

'The machines are also incredibly quiet. I sometimes have to go and physically check they are actually running.'

He added: 'The project has been handled superbly by the Cool-Therm team from start to finish. The installation has delivered everything promised - and more. In terms of both energy efficiency and noise, the Turbomisers are excellent.'

On the day of our visit, the energy monitoring system indicated that one of the chillers was developing 182kW of cooling power while consuming 13.2 kW of electrical power. This equates to an impressive EER of 13.79.

Dave Blackmore said: 'We believe Turbomiser has great potential for application across a range of process industries. The steady cooling requirement provided by a process heat load, plus Turbomiser's proven efficiency and reliability, mean it is ideally suited to such applications.'

The Photronics installation is based on standard HFC versions of the award-winning Turbomiser technology. The latest generation of the chiller uses the new generation HFO1234ze refrigerant, which has zero ODP and a very low global potential (GWP) of just 6.

Trials to date suggest that the energy efficiency of the new HFO chiller compares favourably with Turbomiser systems running on R134a, while benefiting from the low GWP and reduced carbon footprint.

Ken Strong, managing director of Cool-Therm, says: 'With a much lower GWP and efficiency that matches or is better than R134a, the new HFO Turbomisers offer an attractive and practical green solution, which delivers both for the environment and for clients seeking to cut their running costs and carbon emissions.'

The technology behind Turbomiser is said to be proven, with some 200 installations across the UK in applications as diverse as hotels, data centres, universities, commercial offices and, now, industrial process applications.

A recent installation of six Turbomisers at Colt Technology's data centre in Wapping, London is claimed to have resulted in a 55 per cent reduction in energy consumption - and significant reductions in service and maintenance costs.