Breakthrough in solar energy storage

The hydrogen economy is heralded in certain quarters as the green alternative to oil as an energy carrier. At present the vast majority of hydrogen generated is generated from natural gas. So right now a hydrogen fuel cell car, is most likely still ultimately reliant on a fossil fuel source, natural gas, to provide the hydrogen required. In the future of course the thesis is that we could use renewable energy sources to split water into hydrogen and oxygen and generate our hydrogen in that way, thus getting away entirely from fossil fuels.

There was an interesting development on this front reported in the media last week. Scientists at the Massachusetts Institute of Technology University have developed an efficient method of using solar energy solar energy to produce hydrogen from water. Nothing new there I hear you say. But the breakthrough appears to be the use of some specific catalysts which make the process of splitting the water into hydrogen and oxygen much more efficient and therefore viable.
There is no doubt catalysts can work some magic and if they have identified something that can do this here, they may well be on to something.

Daniel Nocera of the Massachusetts Institute of Technology in Boston, said the discovery could remove one of the major obstacles that has prevented solar power from being taken up widely as a viable alternative to fossil fuels such as oil and gas.
“The discovery has enormous implications for the large-scale deployment of solar since it puts us on the doorstep of a cheap and easily manufactured storage mechanism. The ease of implementation means that this discovery will have legs,” Dr. Nocera said.

So will solar panels and water solve our energy problems? Dr. Nocera thinks so stating that ‘sunlight has the greatest potential of any power source to solve the world’s energy problems given that in one hour enough energy from the Sun strikes the Earth to provide the entire planet’s energy needs for a year’.

Now there is another group out there, more of a fringe element perhaps, which is proposing the idea that you run your car on water. There is some interesting discourse and commentary on this in the green tech gazette. If you really want the hyperbola and sales pitch on this, check out ‘Run Your Car with Water

The basic premise is that you can use electrical current from the alternator in your car to split water into hydrogen and oxygen. The hydrogen is then burned along with the gasoline which helps increase fuel efficiency. I have to say I am very skeptical about this. I am inclined to think there is no such thing as a free lunch. The First Law of Thermodynamics states that: In any reaction, energy cannot be created or destroyed. The energy to split the water has to come from somewhere and in your car the energy source is your gasoline. If you use the alternator in your car to run your A/C it consumes fuel, so too would running your alternator to generate hydrogen. In fact the new Toyota Prius will have solar panels on the roof to power the A/C for this very reason.
However ….. a caveat to this, may be if there is a synergistic or catalytic effect of co-burning hydrogen with gasoline which makes the whole process more efficient (at present your typical car is about 20% efficient, i.e. 20% of the energy in your gasoline tank goes into moving the vehicle, the rest is lost mostly as waste heat).

Also if you were able to use say for example the braking energy of the car to generate electricity and use this electricity to split hydrogen, THEN you would be taking advantage of wasted mechanical energy to produce that hydrogen fuel. Again, the Toyota Prius already takes advantage of this phenomenon to power the battery.

Paul O’Callaghan is the founding CEO of the Clean Tech development consultancy O2 Environmental. Paul is the author of numerous papers on environmental technologies and lectures on Environmental Protection technology at Kwantlen University College. He is chair of a technical committee on decentralized wastewater management in British Columbia, is a Director with Ionic Water Technologies and an industry expert reviewer for Sustainable Development Technology Canada.