Window technology opening up energy efficient buildings

European researchers have developed and are currently testing a water flow glazing system designed to turn windows into efficient solar energy collectors.

Belén Moreno Santamaría is an architect at the Polytechnic University of Madrid and an expert in high-performing buildings. He explains how the technology works:

"The system is based on two glass panels. Inside the chamber, instead of - as is far more common - having air or gases like argon, we have water. The water flows in a closed-loop circuit. This water exchanges heat with what we call a 'primary energy system'; it can be a geothermal system, or a heat pump or a buffer tank, depending on the energy strategy the building is aiming at.

"Each glass panel is independent, and all of them take part in this closed loop circulation system.

"Water is very good at generating heat. This allows us to grab the energy from solar radiation in this water sheet that is constantly flowing. All the heat that we can capture can be transported to other parts of the building where heat is needed. Or the heat can also be transported and kept in a temporary energy storage system for later use in other buildings also in need of heat".