Performance of low-temperature district heating for low-energy houses

A Low Energy District Heating (LEDH) network supplying district heating water with temperature 50°C was built in Lærkehaven-Lystrup, Denmark, as a part of the ongoing “Energy Technology Development and Demonstration Programme” [EUDP, 2008] focused on “CO2-reduction in low energy buildings and communities by implementation of low temperature district heating systems”. The network supplies 40 detached Low Energy Houses built in accordance with the requirements of the Danish low energy class 1. The project aims to test and evaluate in real conditions the concept of LEDH for the supply of low energy houses, which was previously developed and reported in the project “Development and demonstration of low-energy district heating for low energy housing” [EFP, 2007]. Two different concepts of low energy district heating substations are tested, and measurements of their performance aim to document that LEDH is a proper solution for sustainable heating systems and answer the question which concept of used substations is more favourable to be used in detached low energy houses. The preliminary results show that LEDH can provide low energy buildings with space heating and domestic hot water (DHW) with high comfort, good economy and proper cooling of district heating water, and it is a good solution for low energy buildings even in areas with decreased heat demand as detached houses settlements.