Plants miraculously create clean energy using only sunlight and water, and until recently, we’ve only been able to look on in envy. All our attempts to mimic photosynthesis have been expensive and energy intensive. But a new start-up aims overcome those challenges: Sun Catalytix, founded by Daniel Nocera, a chemistry professor at MIT, just opened shop thanks to a $700,000 seed investment led by Polaris Ventures.
That might sound like a small sum, but Nocera has been an epicenter of buzz ever since last year, when he first published the research behind Sun Catalytix. His discovery splits water into hydrogen and oxygen, and the process sounds disarmingly simple: He started by placing a small strip of platinum into a vat of water mixed with cobalt and phosphates. Running a small electric current through the water, he found that the water’s oxygen atoms bubble away, leaving pure hydrogen. Pure hydrogen, of course, is an excellent way to store energy.
Typically, the electricity generated by solar panels is stored as either water pumped uphill or in batteries. Both are expensive and inefficient. Batteries, for example, store just 300 watt-hours of energy per kilogram, compared to 13,000 watt-hours for gasoline. Nocera envisions a different system. Vats performing his chemical process would be attached to solar panels, and some of the electricity generated by those panels would power the water-splitting reaction, leaving hydrogen behind in the bargain.
There are still several problems to be solved: Sun Catalytix needs to replace the platinum used in Nocera’s process with something cheaper, for example, and the large-scale engineering process is still pro forma. There’s also competition, Nanoptek is pursuing its own catalytic, water-splitting process, and has already raised $4.7 million in Series A financing. For now, both companies are in stealth mode, refusing press inquiries. Yet the goal is close enough to see, at least in outline: A cheap way to get energy from the sun, just like plants do.