Can windows to accumulate energy while contributing to cooling or heating the interior of the buildings? The answer comes from Vaduz, the capital of Liechtenstein, the show Futuris on euronews.

It resembles a conventional container, but is not. This is due to these windows have cover them with special fluids. The outer surface of the window in this way is able to collect sunlight and convert it into energy and the inside of the window contribute to the change of temperature in the container.

The windows are fed with a special liquid that can be painted. thereby converted into an active tool for energy savings. And not only.

For Anne Sophie Zapf, architect at the University of Liechtenstein and the European coordinator Fluidglass program: "The windows can provide shade so as to protect from the rays of the sun. They also help to heat or cool the interior. And they can be converted to solar panels. Absorb sunlight and use its energy consumption within the building. "

Ideally each window can produce up to one kilowatt of energy per hour (1 KWh).

The liquid in the window is a mixture of water, antifreeze, and magnetic particles. Scientists say the main challenge was to ensure long-term stability.

Therefore they sought particles with very precise characteristics.

According to Daniel Gkstol, mechanical engineer in NTB: «The particles should not be welded must not form a group. They should not remain for long in the window, but should be kept in a liquid and, if necessary, should be easy to filter. "

It is also necessary to ensure that the liquid injected into the windows safe, seamless and efficient manner.

As Stefan Frei explains mechanical engineer, NTB: «The main difficulty for us was to find the right mode. The glass must not operate under pressure, because in this case will be deformed with the lapse of time, and will not have the normal distribution of the particles in the glass. This means that the whole process should be operated at low pressure. Therefore, the circuit changes from excess pressure in the low pressure '.

Sophisticated computer models are also needed to determine to what extent and under what conditions, the windows can better regulate the temperature inside.

For Laura Baoumgkartner, civil engineer at the University of Liechtenstein: "We have confirmed that you do not need any additional heating or cooling system, such as an air conditioner or a heater.

This is one of the important things that we set in the computer. Now should the findings be confirmed through real testing of the container. "

Tests conducted in Vaduz winter and Cyprus in the summer, will show if the windows are actually able to heat or cool the space inside the container.

Waiting for the results, the researchers have already begun to think of the future.

"We expect the main application could be a multi-storey office building with a high percentage of glass surface on the facade. But we have to find solutions, as the wind makes it difficult to cover buildings with large glass surfaces. Anyway large office buildings is our main objective, as individual homes have less glass surface, and to be effective, our system needs as much glass as possible. "

Scientists say that these energy efficient windows could hit the market in less than four years.