Scientists Develop First Practical Artificial Leaf March 28, 2011Posted by Metabiological in Ecology, Science.
Tags: ecology, environment, renewable energy, science
This is all kinds of awesome. Researchers have developed the first practical example of an artificial device capable of producing electricity through the process of photosynthesis. In short and artificial leaf.
About the shape of a poker card but thinner, the device is fashioned from silicon, electronics and catalysts, substances that accelerate chemical reactions that otherwise would not occur, or would run slowly. Placed in a single gallon of water in a bright sunlight, the device could produce enough electricity to supply a house in a developing country with electricity for a day, Nocera said. It does so by splitting water into its two components, hydrogen and oxygen.
Holy renewable energy Batman. This is the holy grail of renewable energy research. A device that enables us to power our society using the non-polluting and completely renewable energy of the sun AND it helps to bring down atmospheric concentrations of CO2. This is so good that at first I wasn’t sure this wasn’t a prank or an early April Fools joke but it seems to be legitimate.
Now if you’ll allow me to come down from cloud 9 for a moment there are of course practical considerations that need to be addressed. First and foremost is cost. Though the article mentions that one of the things making this new “leaf” practical is the fact that it uses lower cost materials than previous models it still remains to be seen whether the technology can scale up and compete with more traditional fuel sources.
Secondly, and more important in my opinion, is the question of water. The device splits water into it’s component parts (hydrogen and oxygen) and uses them to make energy. This of course means that for the device to work it will need a steady and most likely substantial supply of water. The problem is that the water crisis is the biggest environmental problem you’ve never heard of. Humanity is already using more than half of all world runoff for our own purposes leaving very little for the rest of the natural world. Adding another human use for water may push us over the edge in terms of our water consumption.
I’ll add one caveat to that. The article didn’t mention if the water had to be fresh. Terrestrial plants need to use fresh water for physiological reasons, primarily to maintain levels of salt concentrations in their tissues (I’m not going into the details, Google it if you’re interested). However there doesn’t seem to be any reason apparent to me why these artificial leaves couldn’t use salt water for their purposes. If that turns out to be the case then my water concern is largely moot since salt water is one thing this planet has plenty of.
Finally I will offer not so much a problem as an interesting thought experiment. If this device works by splitting water into hydrogen and oxygen then presumably at least some of that oxygen will be released into the atmosphere. Done on a large enough scale, like if this technology takes over as our primary power source, it could conceivably alter the composition of the atmosphere enough to produce changes in the biosphere. An greater abundance of oxygen could be beneficial to certain species of animal life allowing them to extract more oxygen with fewer breaths and therefore generate more energy at a lower cost to themselves. Incidentally this is also predicted to happen to plants as CO2 concentrations rise. Of course a greater abundance of oxygen could also lead to a greater risk of wildfires and could lead to oxygen toxicity in vulnerable environments.
Difficulties aside I am completely supportive of this kind of technology and look forward to seeing it break into the mainstream.