The new Turbomiser chiller with its Turbocor oil-less compressors is said to be breaking new ground in energy efficiency - a claim that is now being proven at high profile UK hotels.

Chillers based on the oil-less centrifugal Turbocor compressor have been around for a while. Their compact design, variable speed capability and magnetic bearings are known to deliver a combination of excellent performance and class leading energy efficiency. Now, however, leading Italian manufacturer Geoclima claims to have developed a new approach to harnessing the benefits of the innovative centrifugal machines that takes the technology an important stage further – and delivers unprecedented energy savings for clients. Recent high profile installations in the UK highlight the outstanding performance of the Turbomiser chiller, and substantiate the claims being made. The project was carried out recently 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. Limited roof space meant two of the chillers needed to be located in space previously occupied by the  cooling towers. In addition, the main condenser water riser had to be converted for chilled water use. There were also strict planning conditions regarding noise.

Energy savings

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. As a result, 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 energy performance is attributed to a combination of flooded evaporators to maximise heat exchange, high efficiency fans and control technology fully integrated with the compressor control. 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 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.”

Ian Mundie says: “There is no doubt that Turbomiser is a technology whose time has come. We believe it has an important role to play in delivering what the market needs, and with a pay-back that is shortening with every rise in energy prices. The level of interest from clients supports this.” Ken Strong added: “With end users under pressure to reduce costs and their carbon footprints, we are convinced that the future of medium capacity water chillers will be oiless technologies, based on small centrifugal compressors with flooded evaporators, coupled with high efficiency fans. Turbomiser delivers this in a compact package, proven to work.”