Climate change caused by global carbon emissions has spawned a massive international effort to begin generating electricity from clean, renewable sources, such as the sun. A smaller, but equally important international effort has been spawned by the growing demand for water caused by global population growth. These may seem like two entirely separate issues, but IBM has found a way to solve both of these problems at the same time.
In partnership with Airlight Energy, IBM has developed a 30-foot solar concentrator is shaped like a sunflower and is capable of not only generating electricity, but also desalinating water to make it drinkable. This kind of technology would be incredibly useful in hotter climates, deserts in particular, where there is an abundance of sunlight and a scarcity of fresh water.
Called a High Concentration PhotoVoltaic Thermal (HCPVT) system, each one is a parabolic dish that’s comprised of 36 mirrors that are made of recyclable, silver-coated plastic. All of the mirrors concentrate sunlight onto photovoltaic chips that convert a whopping 80% of the sunlight harvested into useful energy.
On a sunny day, each chip is capable of producing up to 57 watts, and an entire array could, with the entire dish generating up to 12 kilowatts of electrical power and 20 kilowatts of heat, provide more than enough energy and heat to supply several average homes.
The problem is that the chips become extremely hot as a result. In order to combat this issue, a liquid cooling system was added to the array which could, with proper modifications, also work to produce fresh water.
“For example, salt water can pass through a porous membrane distillation system, where it is vaporized and desalinated,” said an IBM researcher. “Such a system could provide 30 to 40 liters of drinkable water per square meter of receiver area per day…a little less than half the amount of water the average person needs per day according to the United Nations, whereas a large multi-dish installation could provide enough water for a town.”
Read more about the story at Inhabitat.