2.5 Building air conditioning

Secondary cooling systems, using ammonia or hydrocarbons as primary refrigerants, are available for building air conditioning. In these systems the primary refrigerant chills water (or glycol) which is circulated around the building to provide the cooling. Usually, the primary refrigerant is situated outside the main building in order to minimise safety risks.

These systems are commercially available in numerous countries, through a variety of manufacturers. Examples of companies installing secondary cooling systems for commercial air-conditioning, and sites where such systems are already operational

• APV Baker company in the UK.

• Sabroe company have installed secondary cooling in a variety of locations, including cruise liners and Bodo Airbase in Norway.

• ABB Stal installations include Dredsner Bank and Opel(Germany), Palais Grand Ducal (Luxembourg), and PUB Department Store (Sweden). In North America, Stal Refrigeration are suppliers of ammonia-based air conditioning equipment.

• Integral Technologie GmbH (Germany) and Solmecs Flo Ice Systems Ltd. (UK) have installed secondary cooling systems, using Flo Ice (TM) as the secondary coolant, in a number of applications, including air-conditioning of commercial buildings - banks and office buildings - in Germany, Switzerland, Netherlands and the UK.

• A major manufacturer/installer in the UK, Morris and Young , is now providing cooling systems using the Calor Gas hydrocarbon range of products.

• In the UK hydrocarbon based air conditioning has been installed in the offices of the National Trust and London Transport.

• Australia Post has decided that hydrocarbon based air conditioning represented the best option for their sorting offices.

• The large Italian manufacturer De'Longhi launched a new line of propane cooled portable air conditioners called Pinguino ECO in 1995. The portable air conditioner is for both home and office use.

An alternative to vapour compression is the use of absorption systems. This is particularly suitable for air conditioning where there is a source of waste heat available. In the UK this technology has been installed by the BBC, the National Portrait Gallery and University College London. British Gas are a proponent of this type of system. Elsewhere, absorption systems have been installed in banks, restaurants, libraries and offices.