The project was carried out at the world-famous Dorchester Hotel, on London’s Park Lane. The installation has a combined chiller capacity of 3MW, and involved the installation of three Turbomiser chillers, model TMA 1050/34, each in turn housing three high efficiency Turbocor compressors.

The plant was supplied by Wimbledon-based specialist Klima-Therm/LH plc, while consulting engineer on the project was Cudd Bentley Consulting (Birmingham office), and the installer All Group Services.

LH plc de-commissioned and removed the existing water-cooled, R22-based Carrier chillers and cooling towers, which had reached the end of their working life. This was done in stages to minimise cooling down-time during final changeover.

The new plant was sited externally, with one chiller positioned on the roof of the rear third floor, and two chillers on the roof of the tenth floor, freeing up the hotel’s basement plant room.

Site constraints included limited roof space, with two chillers located in space previously occupied by the cooling towers. There were also strict planning conditions regarding noise. In addition, the main condenser water riser had to be converted for chilled water use.

The key benefit for the client of the Turbomiser design was anticipated savings in running costs – to be achieved through improved chiller energy performance and use of air-cooled condenser, saving on water and chemical treatment costs.

Since being installed, the system is reported to have delivered in excess of £10k savings in energy costs per month, compared with the previous system. This is even better than the substantial savings of £8-9K per month savings anticipated.

With this level of saving, the installation is expected to deliver a payback on the additional capital cost over conventional chillers in the first year.

The other significant advantages of the solution were the compact dimensions and low weight of the Turbomiser chillers. This enabled the new machines to be sited on rooftops, freeing up the former plant room space for alternative use.

The chiller’s outstanding energy performance is due to specific design features incorporated in the chiller by Geoclima. It uses a combination of flooded evaporators to maximise heat exchange, and therefore cooling capacity, and employs control technology fully integrated with the compressor control, plus high efficiency fans.

Ian Mundie of Klima-Therm says: “The Turbocor compressor is a superb and innovative piece of engineering, however Geoclima has taken it a stage further. By harnessing its capabilities to the full, Turbomiser builds on an already impressive machine and delivers truly outstanding performance.”

The approach ensures maximum COP is delivered at all times, optimising chiller performance in response to changing ambient temperatures and load.

Ray Pask, chief engineer at The Dorchester Hotel, said: “The installation has delivered everything promised, and more. I am a strong believer in Turbocor technology, having specified it before on another high profile project. It offers major efficiency benefits, and the oiless bearings make start-up from stand-by mode straightforward.
“The Turbomiser chillers installed at The Dorchester Hotel have worked superbly and the energy savings already achieved are substantial, and should result in an even better pay-back time than anticipated.

“We look forward to continuing to benefit from the excellent performance of the system and the substantial savings in running costs over its lifetime.”

The projects described here provide a compelling argument that few clients can afford to ignore.