Four district heating plants in southern Jutland will be converted to make use of solar energy, engineering consultancy firm Rambøll reported in a press release last week, creating the largest solar heating plants in the world.
The new plants will measure between 40,000 and 80,000 square metres, making each one larger than existing solar plants in Denmark and Saudi Arabia.
Fuel for the plants is currently supplied by natural gas. Rambøll, which will perform all the consulting work for the projects, reported that half of the fuel will come from solar energy, while the other half will come from a combination of natural gas and heat pumps.
“The new solution means that citizens will be able to avoid the expenses of high fuel taxes, thus reducing their heating bills by 15 to 20 percent,” Flemming Ulbjerg, a senior consultant at Rambøll, said in the press release. “Today, solar heating is the cheapest solution, compared to other alternatives such as natural gas and biomass, even though these are also tax-exempted.”
Solar panels, which are placed in fields next to the four heating plants, will collect heat from the sun’s rays, which will then be used to heat water, according to Rambøll. The water is then transported to a district heating station and converted into heating.
Such a technique is well-known in private residences, where solar panels are often installed on the roof in conjunction with a hot water tank.
Denmark’s less-than-balmy climate makes it important to store seasonal deposits of thermal energy for later use, Rambøll reported. “These stores can contain somewhere between 100,000 and 200,000 cubic metres of water and will be placed 10 metres underground,” the press release explained.
“The reason why a solar heating plant this big can be established at all is that we already have lots of district heating plants that we can transfer the heat to,” Ulbjerg said. “This is a unique thing for Denmark and it will probably take a while before we see solar heating plants this big in other countries.”
While plans are still in the design stage, the first plant will be completed and ready for use by 2014.