Improving energy efficiency by Optimizing the Return Temperature (RTO) in DH systems

High return temperatures in district heating systems result in huge energy waste. If the return temperature is lowered a few degrees significant energy savings can be achieved, as Return Temperature Optimization (RTO) result in the following benefits:

1. Lower heat loss from the district heating network
2. Lower pump costs associated with less pumping needs
3. Larger capacity in the network, which means possible to connect consumers
4. Lower production costs and better operation, including highly improved fuel efficiency

In Denmark DH systems supplies heat approx. 63 % of all buildings and are prevalent in all major cities. Optimizing return temperatures in Denmark alone will mean big energy savings, and will be an essential tool for district heating companies in an effort to meet the DEA´s energy savings targets. Globally, most DH systems operate with higher temperature levels than in Denmark. Therefore optimization of both supply and return temperatures has strong export potential. A key element is the use of meter data from all remote reading systems (BigData), as from example Kamstrup metering system. Presently DH companies invest large sums in smart meters, mainly for billing purposes, both in Denmark and abroad. The project will involve these systems, but with the technical use of meter data in mind, which is analogous to the smart grid idea in the electricity industry.
Aim of the project for the energy technological and commercial area
The goal of the project is to bring the software solution up to a stage where the RTO has matured to the Danish and the international market.
The Danish market position in the DH world is maintained only if the industry continues to develop innovative solutions. RTO and real smart-grid use of meter data and real-time models will arouse international attention and pave the way for export of Danish DH technology.