Solar heating: a bright alternative

Energy from the sun is the single largest source of energy on Earth. The daily insolation of light from the sun on our globe is approximately 6,000 times the total amount of energy consumed daily on Earth.

Solar heating represents a great potential

Solar heating technology

Energy, light and heat from the sun have been used by humans since ancient times. Already at the end of the 15th century Leonardo Da Vinci suggested that solar energy could be used at a large scale to heat up water. Today the utilisation of solar energy is much more than just an idea. Over several decades a lot of resources have been spent on being able to utilise this fantastic source of energy. Solar energy is a well-known alternative energy source. This is why it is one of the fastest growing alternative energy sources – for the benefit of our globe and the environment.

Solar heating panels transform the sun's energy into heat or thermal energy by heating up water. Solar heating is one of the most well-known and environmentally most sustainable alternatives over traditional energy sources. Ramboll has since 1994 had a strong commitment to solar heating and is the leading consultant within the area in Denmark. Over the past decade we have been involved in the establishment of ten of the largest solar heating facilities in Denmark. The life span for these facilities is expected to be 30 years.

An efficient alternative energy source

"In line with the increasing popularity and establishment of wind power for producing energy, solar heating becomes feasible as well. As wind power takes over the production of electricity from the traditional Combined Heat and Power plants, these plants are increasingly focussing on the production of heating rather than electricity. Solar heating systems help make the production of heating much more efficient," explains Flemming Ulbjerg, expert in solar energy at Ramboll.

According to Flemming Ulbjerg, the cost of producing heating at district heating plants will be reduced with 5% from the very first day of implementing solar heating. During the 30-year life span of the solar heating facility, this may increase to a reduction of 15-20% of the cost of producing heat. A cost reduction that ultimately benefits the consumers of district heating.

"Many of the solar heating facilities we provide consultancy for have a Net Present Value of 125-150 DKK/MWh. This is far below the alternatives, most frequently being natural gas at a cost of more than 400 DKK/MWh. It is also cheaper than biomass such as straw or wood chips," says Flemming Ulbjerg.

A shining example

The development of solar heating used for district heating in Denmark has to a large extent been influenced by the development of solar heating on the little Danish island, Ærø. On this island there is no access to natural gas, meaning that other energy sources had to be explored.

"Ærø is a good example of how the future energy supply could look in Denmark. In the long run it wouldn't be sensible to be dependent on the supply of natural gas. And the amount of available biomass is limited, and therefore has to be used with care," says Flemming Ulbjerg.

Marstal District Heating has for several years been the worlds' largest solar heating facility with 18,000 m2 of solar heating panels. There are plans to double this area to approximately 35,000-40,000m2 in total.