On a south-facing roof surface on the environmentally friendly block (Block B) a 70 m² solar collector connected to the heating system is set up. The solar collector primary produces heat for domestic hot water and secondarily to the heating of rooms. If the water from the solar collector is colder than the water heating up the domestic hot water, the water from the solar collector is diverted to the floor heating system. If the water from the solar collector is colder than the water to the floor heating, it will be diverted as well.

The flats in both blocks are heated through a low-temperature floor heating system connected to the city’s district heating and in Block B the floor heating is connected to the solar collector. Furthermore, an addition of 50 mm isolation has been placed in the walls and 100 mm on the ceilings in Block B compared to the conventional block (Block A). Block A is build according to the current building regulations.

These initiatives have resulted in heat consumption in Block A on approx. 70% of the consumption of heat in Block A. It is difficult to point out precisely to which level the different initiatives have influenced the result.

The heating systems in the two blocks are built up quite differently. In Block B the heat comes from both the district heating system, solar collector and the ventilation system.

However, the effect of the solar collector can be measured precisely regarding the domestic hot water. It turns out that the residents in Block B use only half as much heat for domestic hot water compared to the residents in the conventional block. This is due to the effect of the solar collector.

Solar system costs: 218,000 DKK (29,300 €)

Estimated pay back time: 12 years. The payback time is calculated based on a kWh price of 0,60 (0,08 €) and a yearly saving of DKK 30,000 (4,037 €).

Supplier of technology:

ARCON Solvarme A/S
Jyttevej 18
DK-9520 Skørping
Phone: +45 98391477
Fax: +45 98392005
e-mail: export@arcon.dk
www.arcon.dk

ARCON Solvarme produces and markets four different flat-plate collector models for use with domestic solar energy systems and one special model for large plants. Furthermore Arcon offers storage-tanks, control-units, etc. for implementation in complete ARCON solar energy systems.