Solvarmeanlægs energibesparelser

Abstract

Energy savings for a number of new solar heating systems in one family houses have been determined by means of information on the energy consumption of the houses before and after installation of the solar heating systems. The investigated solar heating systems are marketed by Velux Danmark A/S, Sonnnenkraft Scandinavia A/S and Batec Solvarme A/S. Solar domestic hot water systems as well as solar combi systems are included in the investigations The houses have different auxiliary energy supply systems: Natural gas boilers, oil fired burners, electrical heating and district heating. Some of the houses have a second auxiliary energy supply system. The collector areas vary from 1.83 m² to 9.28 m². Some of the solar heating systems are based on energy units with a new integrated natural gas boiler and a heat storage for the solar heating system. The existing energy systems in the houses are for most of the houses used as the auxiliary energy systems for the solar heating systems. The yearly energy savings for the houses where the only change is the installation of the solar heating system vary from 300 kWh per m² solar collector to 1300 kWh per m² solar collector. The average yearly energy savings is about 670 kWh per m² solar collector for these solar heating systems. The energy savings per m² solar collector are not influenced by the solar heating system type, the company marketing the system, the auxiliary energy supply system, the collector area, the collector tilt, the collector azimuth, the energy consumption of the house or the location of the house. The yearly energy savings for the houses with solar heating systems based on energy units including a new natural gas boiler vary from 790 kWh per m² solar collector to 2090 kWh per m² solar collector. The average yearly energy savings is about 1520 kWh per m² solar collector for these solar heating systems. The energy savings per m² solar collector for these systems are also not influenced by the solar heating system type, the company marketing the system, the auxiliary energy supply system, the collector area, the collector tilt, the collector azimuth, the energy consumption of the house or the location of the house. That is, yearly energy savings for new solar heating systems in one family houses are high, ranging from 300 kWh per m² solar collector to 2090 kWh per m² solar collector. If the existing energy system is used as the back up energy system for the solar heating system typical yearly energy savings vary from 500 kWh per m² solar collector to 800 kWh per m² solar collector. For solar heating systems with a new energy unit including a new natural gas boiler typical yearly energy savings vary from 1000 kWh per m² solar collector to 2000 kWh per m² solar collector.