Innovation provider



Thomas Lindström
Telephone :+46 8-581 76100


EVI HEAT SPLIT SUN is a heat pump that supplies your home with environmentally sound heating. It was specially developed for households with stringent demands on cost, comfort and the environment. What makes the solar heat pump unique is that it uses heat from the sun combined with solar heat stored in the earth or groundwater to heat your house and hot water.
The sun lights your roof annually for 800-1,000 kWh/m2, which means that a house with a roof area of 120 m2 absorbs 120,000
kWh of solar energy each year. EVI HEAT SPLIT SUN uses this free solar energy – helping to reduce your carbon footprint and your energy costs.
Buy “green” electricity and become 100% environmentally friendly
A solar heat pump can heat your house up to 80% with energy from the sun. The remaining 20% depends on you. If you buy “green” electricity from your energy provider, you can heat your house 100% with renewable energy.
Save another 40% or so compared to traditional ground-source
A solar heat pump with a solar panel consumes about 40% less electricity than comparable ground-source heat pumps. And it can also produce hot water up to 85ºC in the summer. The low energy consumption also means a minimal effect on your pocketbook when electricity prices rise. So a solar heat pump is especially good for households with stringent demands on cost, comfort and the environment.
Annual efficiency over 500%
The solar function in EVI HEAT SPLIT SUN helps reduce compressor operating time but also increase its power and efficiency. In practice, this means that the heat pump delivers five times more heat energy than it consumes in a year.
The highest efficiency in the market, 700%
The coefficient of performance, COP, can be as high as 7.0 (efficiency 700%) because the solar panel increases the temperature of the brine to a maximum 20ºC before it enters the heat pump. On average, COP is 5.5
(efficiency 550%), which is by far the most efficient in the market.
Ready to add a solar panel right now or at a future date
EVI SPLIT SUN has all the necessary solar equipment preinstalled and is ready to be connected to a solar panel. Without the panel, it works as a traditional heat pumps and still has the highest efficiency (COP). All this is due to the highly efficient Benchmark compressor and optimised heat pump circuit. The solar heat pump also uses ground-source or water-source heat as an energy source along with solar and can be connected to any fluid heating systemin your house, such as radiators, convectors or floor heating.


All EVI HEAT pumps are solar steered from the factory, but depending on if you wish to use solar heat in combination with heat pumps directly or in the future there are various options. You can choose between two different heat pump types: GeoSun I incorporates a hot water tank and sun control unit or GeoSun II without tanks, but quite ready to work with solar collectors from the start.
 Many of our clients wish to connect the solar panel or other external source of heat to its heat pumps in the future. Until the fall of 2007, they referred to buy our solar pump with built solar steering and separate tank (EVI HEAT SPLIT SUN), which becomes a more costly and bulky solution in comparison with a standard heat pump. We have therefore developed a standard heat pump with is integrated to the hot water tank in which steering is ready to deal with solar. When it is time to utilize solar energy supplemented this heat pump with solar panels and solar modules. The module contains both the physical sun control typically found in the solar pump and makes the standard heat pump to a complete solar pump.

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Exported to other countries 

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National Contact Point

Uwe Fortkamp
IVL Svenska Miljöinstitutet AB
Valhallavägen 81
P.O. Box 210 60
114 27 Stockholm

Tel: +46 8 598 56300
Tel: +46 8 598 56390