– Here you can feel that it is hot, says Geir Andersen in Drammen Eiendom. He feels with his hand the pipe from one of the solar collectors on the roof. – Water circulates inside, which becomes very hot when the solar collectors are black, have glass and stand in the sun, says Andersen. – Instead of heating the school with expensive energy in the winter, we save on solar energy in the summer, says Geir Andersen in Drammen Eiendom. Photo: Kjartan Rørslett / news He is the manager of maintenance and environment in the municipal company and an important driving force behind the “geothermosis” at Fjell skole. They fill up the special heat storage throughout the summer when the sun shines most. “Power plant” on the roof Sun and summer heat are stored in the thermos. In winter, it is brought out again and used as underfloor heating. On the roof, the school has its own small “power plant” that harvests energy from the sun. The heat from 125 square meters with solar collectors can go straight into the thermos or be used at school in the spring or autumn. 1,000 square meters of solar panels produce a lot of electricity. During the summer months, the current drives a powerful heat pump that extracts the heat from the air. – It is 250 kilowatts, runs on electricity from solar panels and draws a lot of heat into the thermos, say Geir Andersen Trond Haugan, Rune Simensen and Geir Andersen from Drammen Eiendom on the roof of Fjell school. Behind them are the solar collectors that heat water. In front of them are some of the solar cells that produce electricity, among other things for the heat pump. Photo: Kjartan Rørslett / news The thermos is 50 meters deep The thermos itself consists of 100 tubes of water that go 50 meters into the ground under the car park at the school. The heat is sent down there from May to September. – The geothermal system is like a 15-storey high block, and it is the stone that gets warm, says Geir Andersen. At the last measurement, the thermometer showed that the rock massif had become hotter than 45 degrees. – There is a lot of energy, says Andersen. So much so that they have stopped filling it for the season. – We could probably have filled it even more. But now there is enough energy to keep the school warm throughout the winter. We are sure of that, says Andersen. Underfloor heating During the winter, the heat from the thermos is used for underfloor heating in the classrooms, library, sports hall and workroom at Fjell School. It happens almost without electricity being used, even on cold days. An 800 watt circulation pump is what is needed to get the hot water out of the thermos. – That is a bit of the point. The school does not burden the power grid, says Geir Andersen. That is one of the reasons why Enova has supported the work with the geothermal system at Fjell skole. – I have come across different heating systems at several schools, not all of them have been equally good. But this works, says principal Arnstein Eriksen. news visits the school on a sunny September day. On a screen in the technical room, project manager Rune Simensen can see how much energy they harvest from the sun at 3pm in the afternoon. The heat pump is powered by solar power and extracts heat from the air. In the summer, it fills the thermos with heat. The heat pump is 250 kilowatts and runs on electricity from the solar panels on the roof. Photo: Kjartan Rørslett / news – Now the solar collectors deliver 56 kilowatts, the solar cells 41h. So in total we get about 100 kilowatts of solar energy, he says. Along one wall, black pipes run close together before disappearing into the concrete floor. – It is the reed that goes to the geothermal system. There are two pipes, one more and one from inside each of the pipes you see. They are used in different ways, depending on what pays off the most, explains Trond Haugan, also technical project manager at Drammen Eiendom. In the mountain bed below the car park is the geothermos which will keep the school warm this winter. Photo: Kjartan Rørslett Can be used almost everywhere The Geothermal system at Fjell skule in Drammen is special, but the technique can be used elsewhere, says Randi Kalskin Ramstad. She is associate professor II at Norway’s University of Technology and Natural Sciences and a consultant at Asplan Viak. As a specialist in geothermal heating, she has been involved in the work with the geothermal system in Drammen. Randi Kalskin Ramstad, associate professor II at NTNU and advisor at Asplan Viak. Photo: NTNU – This can be done where there is stone and favorable loess conditions, air and sun. So it can be used almost everywhere in Norway, says Kalskin Ramstad. – Is a geothermos a good solution for an ordinary residential building? – No, it probably won’t, the heat loss will be too great. This is more relevant for larger development projects where you need more than one million kilowatt-hours of heat during the year, she says. The solution may be used in the redevelopment of the Nyhavna district in Trondheim, where a geothermal system can provide heat for the new buildings. At Kolbotn outside Oslo, the sports team will use slings of water under the football pitch as a large solar collector in the summer. A heat pump must then raise the temperature of the water even more before it is sent down into the heat storage below the ground. When winter comes, the heat from here will keep the artificial grass track free of snow. – The water in the solar collectors gets very hot and can go straight into the thermos, says Geir Andersen in Drammen Eiendom. He has been a driving force for the geothermal system at Fjell skole. Photo: Kjartan Rørslett / news Norway can get many geothermos – How common can this be? – I think it will take some time before it really gets going, we need to have a few more pilot plants first. But in 10–20 years we should have quite a few such facilities in Norway, says Randi Kalskin Ramstad. While high electricity bills mean that many municipalities turn down the indoor temperature in schools this winter, it is not necessary at Fjell skole in Drammen. Here they have the heat on a thermos. – Instead of using expensive energy to heat the school in the winter, we have a heat pump, solar cells and solar collectors in the summer, when there is a lot of sun. When autumn comes, we turn off the heat pump and heat the building from the thermos, says Geir Andersen. Below this car park is the “geothermosis”.
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This school has summer heat on a thermos – news Norway – Overview of news from different parts of the country
