On a recent fact-finding trip to Denmark, representatives from SAV Systems and Nottingham City Council saw clear evidence that low flow temperatures in heat networks deliver significant energy savings.

The party visited two residential district heating schemes, both operating with
flow/return drop-the-flow-pic2water temperatures of 55°C/35°C – considerably lower than the 80°C/55°C typical in many UK projects. Each of the trial systems saw a fall in heat losses from the distribution network of around 75%, compared to higher temperature systems.

During the tour the party also attended seminars on the future of low temperature
district heating schemes and also visited the Metropolitan Copenhagen Heating Transmission Company (CTR) which is responsible for most of Copenhagen’s district heating.

drop-the-flow-pic1SAV Sales Director Jan Hansen observed: “There are growing environmental and regulatory pressures in the UK to make wider use of heat networks for both large and small scale projects. When we do so, however, it is essential to design the systems for maximum efficiency – and to facilitate the use of a mix of a low carbon heat source.

“Denmark’s experience clearly shows that a key element of meeting these criteria is to design for low system temperatures – even lower than those currently recommended by CIBSE”.