The Royal Festival Hall celebrates its 50th anniversary today. When it was opened, it was considered to be ground-breaking in many ways - a novel design representing the spirit of the time, even though the postwar era in Britain was not easy.
Sterling had been devalued, building costs were high and materials were in short supply. Herbert Morrison, leader of the London County Council (LCC), who was seen as the godfather of the Festival of Britain, was trying to cut through British reserve and encourage innovation.
According to some pundits at the time, the architects - Robert Matthew, Leslie Martin and theatre designer Peter Moro - were crazy to consider a site so close to a mainline rail viaduct. Although there proved to be just a small amount of noise and vibration from passing trains, the design team provided a doubleshelled auditorium to be on the safe side, thereby insulating the performance space by surrounding it with other necessary accommodation.
This type of imaginative and compensatory design was also applied to the building services. One of the least-known innovations, located deep within the bowels of the building, was a bold experimental installation of a unique engine that produced more 'heat energy' than was used for driving it. The supportive energy produced to heat and cool London's new concert Hall was not from coal, oil or gas but the freely available waters of the River Thames.
The luxury of installing an airconditioning system in soot-bound London was seen as a symbol of progress. But the original decision by the LCC to back a demonstration project (designed by engineers in the Ministry of Fuel and Power) to develop a commercially viable energy-saving heat pump, was intended to have a much greater impact.
The government was aware that the US was kick-starting a domestic heat pump market, so, in the 'national interest', the ministry engineers wanted to assess the true economic value of the system and its scope of application.
First invented in 1852, the heat pump is a machine that can extract heat from a low temperature source, such as air, soil or water, and upgrade it or 'pump' it to a higher temperature level. It is like a refrigerator cycle in reverse.
As Oliver Lyle, senior adviser to the government's Fuel Efficiency Committee, wrote in 1947: 'Why should we be ashamed of a device like the heat pump where the Almighty gives us something for nothing, where we can turn useless energy into useful energy.'
In 1950 there had only been one successful application of a heat pump - by the city of Norwich's chief electrical engineer, John Sumner - and the results were encouraging.
In the case of the Royal Festival Hall, water from the Thames was drawn through a centrifugal pump installed below Charing Cross Bridge at a rate of 1,800 gallons a minute to vaporize a refrigerant at low pressure.
Centrifugal compressors were driven at speeds of up to 17,500rpm by two 12-cylinder Rolls-Royce Merlin aircraft engines, converted to run on town gas with specially designed components that allowed for compactness of plant.
In this way, the heat of the primary fuel was supplemented by the latent energy taken from the river. By making use of the heat dissipated from the exhaust of the engines, as much heat energy as possible was abstracted.
The plant was versatile and could quickly be switched over to operate in a cooling mode. It was intended that the full operational data of the 7,600 kilowatt system was to be assessed after a year, with the additional benefit that it would serve the whole festival complex to make it economically viable against the cost of town gas. According to the plant engineer's notes, the system worked.
When the exhibition was over, however, a new government assetstripped the site and with it went the demonstration heat pump.
Two professors of building science at Strathclyde University, Markus and Morris, writing in 1980, quoted earlier pronouncements that the energy requirements had been grossly overestimated and the heat pump grossly oversized. They believed that 'a more favourable situation would have existed had the heat pump been designed to have an output based on the cooling load, rather than the heating load'.
This is partly the basis of the new refurbishment scheme.
New feasibility studies have been prepared by building services engineer Max Fordham & Partners to ensure that a comfortable environment meets 21st century standards.
Design engineer Colin Darlington said that a 'modern heat pump using Thames water was considered', but strictures by the Environment Agency concerning the temperature of any returning high volume of water 'reduced its viability'.
Heat pumps will be used, once again for cooling only, served by bore hole water and ice storage. Even though it is not the same heat source as was originally envisaged, it is good to see that the same energy-saving process is the basis of the new services proposals to be phased in over the next five years.