As a leading player in America’s solar thermal industry, we have heard all the arguments against renewable energy. The sun doesn’t always shine, the wind doesn’t always blow, and there is no way to depend on renewable sources to the same degree we can depend on fossil fuels. Well, officials in Marstal, Denmark have heard the same criticisms. That hasn’t stopped them from generating more than half of the heat required by a town of 2,300 via solar thermal.
Marstal is just one of a small number of communities occupying space on Aero Island off the southern coast of Denmark. It is a community that has long lived according to the dictates of the sea. It is a community that has long depended on nature to supply its most basic needs. So when they decided to embark on a solar thermal project to provide district heating, they were determined to make it work despite the region’s reputation for frigid weather. And work it does.
On the outside of town is a field with more area than six football fields, filled with solar thermal collector panels. Those panels are connected to a network of underground pipes through which flows water used to provide central district heating. The panels collect solar energy, then transfer it to a thermal liquid that is circulated through a heat exchanger. The extracted heat is then transferred to the water circulating through the system.
Year-Round Space Heat
So far you haven’t read anything that would suggest this installation is unusual. Still, you might be wondering how Marstal manages to generate 55% of its heat in an environment that gets limited sunshine during the winter months. They deployed a simple solution that has proven very effective. The Marstal heating project does not rely on anything other than an insulated, underground tank that holds water heated by solar thermal panels.
That’s right; something as simple as burying an insulated tank stores enough heated water to provide more than half of the space heat the town needs year-round. Obviously, it would be better to have a storage solution that could provide 100% of the heat, but that solution is not yet available. In the meantime, a system that provides 55% of the heat is remarkable. Even more impressive is the fact that it puts no additional strain on Denmark’s electrical system.
Denmark is a nation in which roughly 60% of the structures are connected to district heating. This is motivation for Danish officials to figure out how to provide cost-effective centralized heat without having to depend on fossil fuels. They have found that solution in solar thermal.
If They Can Do It in Denmark
It’s not unusual for us to hear that solar thermal is impractical for year-round space heat and hot water. We beg to differ. What many people don’t know is that our patented SunQuest 250®™ solar thermal collector doesn’t need direct sunlight in order to be effective. That’s why it generates energy even in the dead of winter.
Our solar collector panel utilizes evacuated tube technology along with an absorption material that captures ultraviolet energy instead of direct sunlight. That means our collector panel is absorbing solar energy even on cloudy and overcast days. With a properly designed system including efficient storage, an installation based on our patented SunQuest 250®™ solar thermal collectors can provide virtually all the hot water and space heat for your commercial building. If they can do it in Denmark on such a large-scale, we can certainly do it for your building as well.
1. GovTech.com – http://www.govtech.com/fs/This-Energy-Technology-Gets-No-Respect-at-All-but-Its-Cutting-Carbon.html