In order to establish comfortable indoor climate and to avoid installation of conventional radiator heaters, a combined system for ventilation, space heating, and hot water was installed.

Boiler room

District heating
All three complexes are connected to the local district heating system through a boiler room in each building. The heating system uses a low distribution temperature, which means that the water temperature in the piping system and radiators will be lower than in a conventional heating system. Therefore the radiators and the piping system require an increased surface area compared to a conventional system. Radiators are controlled by thermostatic valves and placed in the centre of the dwellings in order to get lower installation costs.

Illustration of the heat exchange system

Ventilation and heat exchange
The heat distribution pipe system is integrated with the ventilation system, which means that the distribution of the hot water to the dwellings passes through a water/air heat exchanger that heats the incoming airflow. The integrated ventilation system moreover includes highly efficient counter flow heat exchangers capable of utilising up to 90% of the energy in the exhaust air. 

There are some differences, however between the complexes. The ventilation in one of the complexes includes low energy heat recovery ventilation systems, supplied with electricity from PV modules integrated in the building facade. The heat exchanger, the ventilation fans and the filters are installed on the outside of the existing wall and a new building envelope was established around the installations. In order to be able to install the ventilation units on the outside wall, it was necessary to reduce the thickness of the heat exchanger and a special unit with built-in filters and fans was developed. The new building envelope is made of transparent glass also acting as a solar wall.

The ventilation system of one of the other complexes installed highly efficient (90%) counter flow heat exchangers in the loft, each with a capacity to cover 10 dwellings.

Solution 1: Special thin design of heat     exchanger with built-in filters and fans

Heat Exchange system in                         the loft

Finally it should be mentioned that the project included an Energy Management System (EMS) that controls and monitors important energy fluxes. Preliminary results confirm that the solar systems function satisfactorily and indicate heat energy reductions of more than 50% and hot water reductions up to 65%.

General information on the technologies:
District heating
Ventilation and heat exchange

Suppliers of technology:
The ventilation system and the heat exchangers are fully integrated with the solar collection system and the PV-modules, which is a solution based on the know-how and products of SolarVent.

Solar integrated heat exchangers:
SolarVent Aps
SolarVent has specialised in solar assisted ventilation solutions, for example solar cell or photovoltaic, PV driven ventilation systems with heat recovery and herein a contribution of electrical power supplied by building integrated PV-modules. SolarVent's know-how embraces experiences on building integrated PV-design with combined use of electricity and heat from the PV-modules where ventilation air is preheated behind the PV-modules.
Address: Valby Kirkevej 5,
DK-2500 Valby
Phone: +45 4032 7882
solarvent@image.dk
www.solarvent.dk