Scientists find key to lock up solar power

Posted by Wolfgang Gruener

Cambridge (MA) – If you have ever looked into installing solar panels on the roof of your home, then you may have found that the technology can cost you tens of thousands of dollars, the power gain is very limited at this time and power is only produced during daylight hours. But, it seems, science is working on each of those shortcomings and we are hearing about possible new solutions, including much more efficient solar cells almost on a weekly basis. In the most recent development, MIT scientist claim they have now found a way to capture solar power, convert it and store it so it can be used during night times.  

There is no doubt the solar energy may be among the greenest and most promising ways of generating electricity, but at least today there are just too many holes in the infrastructure between generating and distributing solar energy to make it a mainstream solution for virtually any household. One of the big holes could be closed soon as MIT professor Daniel Nocera, and Matthew Kanan, a postdoctoral fellow in Nocera's lab, claim to have found a way to store solar power.

The technology is based on the idea to use the sun’s energy to split water into hydrogen and oxygen gases. The oxygen and hydrogen can be recombined inside a fuel cell, creating what appears to be completely carbon-free electricity to power a household or your electric car, day or night. According to Nocera, the key component in the process is a new catalyst that creates oxygen gas from water. The catalyst consists of cobalt metal, phosphate and an electrode.

When placed in water and electricity (which can include solar- or wind-based sources) is applied the cobalt and phosphate form a thin film on the electrode, and oxygen gas is produced. Combined with another catalyst, such as platinum, which can produce hydrogen gas from water, the system can duplicate the water splitting reaction that occurs during photosynthesis.

 

Nocera said that the catalyst works at room temperature and in neutral pH water.

More engineering work needs to be done to integrate the new scientific discovery into existing photovoltaic systems, but Nocera said he is confident that such systems will become a reality. The scientist believes that the technology could become a mainstream solution within 10 years. He also noted that “electricity-by-wire from a central source could be a thing of the past” by then. Of course, solar cells will need to become much more efficient, but considering the fact that the sunlight that hits the earth every hour carries enough energy to power the entire planet for one year, there seems to be enough opportunity to justify increased efforts in solar research.  

Storing solar power, however, is not an entirely new idea and has been described on much smaller and perhaps not as green levels before. For example, car manufacturer Fisker said that it will be offering the installation of house solar panels as an option for its upcoming Karma hybrid sedan. The energy captured during the day is envisioned to charge a battery unit placed in the garage which can be used to charge the car overnight or simply when it is parked in the garage.