Mathias Bahrenscheer (23), David Bonde (23), Nicklas Funk (22) and Caroline Rossing (23) are currently on the fifth semester of their
Design and Innovation programme. They have developed a sustainable refrigerator that pumps water up from the bottom of a lake and uses if for cooling. There is great potential for their invention in developing countries, for example.
By Maja Tolstrup Pedersen
“We’ve designed a fridge that uses water from a relatively cool lake bed to chill the contents. The process involves a system based on a circulation pump. We have used an energy-efficient pump donated by Grundfos that consumes just 3 W, which reduced the energy consumption even further. The pump sends the cool lake water through the copper pipes in the refrigerator, and the only power used for cooling is the power for the pump. This is supplied from solar cells, so the unit as a whole is energy neutral. The now-heated water is then pumped back into the lake.
We tested the fridge and the pump at this year’s Roskilde Festival, where we discovered that the system could cool canned beer down to just two degrees above the water temperature.
During the process, we have discovered that not only does the circulation system have the potential to contribute to the sustainable, energy-efficient refrigerators of the future, but it may also feature a humanitarian dimension, given that it can be installed anywhere with a lake and it doesn’t consume any resources.
This means that in future it can be used in developing countries, for example, where important products such as medicines require cooling. Grundfos has shown great interest in the project and we are currently waiting for the company to check the refrigerator’s function in its test facilities and send us feedback so we can move on.”
From the 'What's up' section in DTUavisen no. 9, November 2014.