What is the liquid used for solar thermal energy circulation?

Our flat solar collector utilize pure water to circulate in the flat solar collectors. Not only is water an environmentally friendly fluid that is available everywhere, it is also an amazing fluid with a heat capasity 5-times better than sand and nearly 10-times than that of steel. To avoid any situations related to freezing or boiling, the water is drained when not in use.

What is the cost of a solar thermal energy system?

The price of a solar thermal energy system depends on the size of the installation and this again depends on your energy needs. By using our solar thermal energy calculator, you can calculate how much energy you need and the area of flat solar collectors you need to meet your energy demands. If you are going to cover the hot water for a family, you probably need no more than 6 m2. Are you going to cover both hot water and heating demands, you can expect between 10 and 15 % of the building area as flat solar collectors. Price experiences indicate that the price per m2 of flat solar collector is around 350, - €, including installation, flat solar collectors, solar heat storage, connections, pipes and a solar thermal energy system control unit.

What is the size of the solar collectors that I need?

The surface of collectors depends on your energy needs. To calculate the amount of solar thermal energy you can download the solar thermal energy calculator You can generally count between 10 and 15 % of the residential area in the form of flat solar collectors, if you heat the home using under-floor heating. A solar water heating system for a family of 4 people need a facility of approx. 6 m2.

Can I place the solar collector in a flat position?

We tested to see how flat our solar collectors can be mounted without compromising the drain-back properties. We have tested several different angles and see that the drain-back is not affected significantly even at only 3 degrees. This allows for "flat" installation of our solar collectors and architectural integration even on flat roofs.

Am I free to place the solar collector where I want?

Yes - our solar collector is based on drain-back. Ie. the circulating fluid is drained back into a storage tank when the temperatures are too low or too high. Many customers have requested a solution to allow this drain-back even when the solar collectors are placed at the same level or lower than the solar heat storage tank. We are pleased to meet our customers demand with this new solution that allows for installation of the solar collectors above, same level or below the level of the solar heat storage tank. Now you may concentrate on the architectural integration rather than the levels of the solar thermal energy system.

Can I combine solar thermal energy systems with other heat sources?

Yes, you may want to combine solar thermal energy with other energy sources. Just keep in mind that the solar energy is stored in a solar heat storage and that this is used as buffer when the sun provides less energy during cold overcast weather. Since you do not know when the sun contributes, the solar thermal energy system should be the first part of the heating system and separated from all the other sources. Other heating should be applied if the flat solar collectors do not have enough solar energy to render. Then you are sure you are not using other energy sources to heat the solar heat storage and you will obtain the best possible operating conditions for your solar thermal energy system.

May I mount the solar collector at the same level as the solar heat storage?

Yes, we found a solution that enables installation of the solar collector at the same level as the solar heat storage. This is particularly interesting if you plan to install the solar collector on a wall or a low roof or in the case where you don't have a basement where the solar heat storage can be placed.

What is the optimum angle for a flat solar collector?

The optimal angle as far north as in the Oslo, Norway area is 75 degrees, but the panels utilize solar energy with about the same efficiency even at common roof angles like 22 degrees. Thus, regardless of an angle at 22 degrees or at 75 degrees, the utilization of the solar thermal energy will be about the same. Even placement on a wall that is 90 degrees will work well.
You can calculate the effect of different solar angles.

Is it profitable with solar energy?

Yes, it's more than enough solar energy even as far north as in Norway. You can expect to harvest between 250 and 800 kWt/m2 og flat solar collectors depending on the location of your site and number of hours of sunshine. This means you pay approx. 0.05 € / kWh if you depreciate the facility over 15 years. The solar thermal energy system is deprecated after 4-5 years if you consider the current energy prices.
Return on flat solar collectors

Is there any solar thermal energy to get during the winter?

The solar radiation varies from about 1200 Watt/m2 at equator to some 150 Watt/m2 in Norway at the winter solstice. This means that even on a very cold winter day of -20 degrees C, you will have valuable energy if you have sunshine. The outdoor temperature has only marginal significance in relation to the solar thermal energy.

What about freezing in winter and boiling in the summer?

Our flat solar collectors are designed to withstand frost and high temperatures, but the liquid that circulates in the panels provides additional challenges during freezing and boiling. Therefore, the solar thermal energy system is designed to drain automatically when the temperature is low (below 10 ° C) or high (above 95 ° C). In case of power failure, the solar thermal energy system drains automatically.

Do I mount a rack on top of the tiles?

Our flat solar collectors are designed to integrate into the roof or into the facade. You may off course mount them on a rack on top of the tiles or outside the wall, but we recommend that you take away the roof tiles or wall cladding where the flat solar collectors will be installed. The flat solar collector is only 83mm thick, so it easyly integrates into a neat and architectural solution.