February 03, 2008
Solar Material Makes Hydrogen From Water
Instead of using photons to produce electricity a start-up is using photons to split apart the hydrogen and oxygen molecules in water.
Nanoptek, a startup based in Maynard, MA, has developed a new way to make hydrogen from water using solar energy. The company says that its process is cheap enough to compete with the cheapest approaches used now, which strip hydrogen from natural gas, and it has the further advantage of releasing no carbon dioxide.
Nanoptek, which has been developing the new technology in part with grants from NASA and the Department of Energy (DOE), recently completed its first venture-capital round, raising $4.7 million that it will use to install its first pilot plant. The technology uses titania, a cheap and abundant material, to capture energy from sunlight. The absorbed energy releases electrons, which split water to make hydrogen. Other researchers have used titania to split water in the past, but Nanoptek researchers found a way to modify titania to absorb more sunlight, which makes the process much cheaper and more efficient, says John Guerra, the company's founder and CEO.
Suppose this Nanoptek approach really works and eventually can be used to make hydrogen cheaply. What to do with it? Hydrogen is still difficult to transport and store. But hydrogen attached to carbon is very useful in both gas and liquid forms. The problem then becomes where to get the carbon? Ethanol seems a good candidate. It contains a partially oxidized carbon that'd be more useful if its oygen got replaced with a hydrogen. That would lead to ethane and eventually ethylene. The ethylene has many industrial chemical uses.
The hydrogen could also be used with the exhaust of an coal electric power plant to combine with the carbon in the carbon dioxide to again make reduced carbon in gaseous or liquid form. A hydrocarbon with longer carbon chains would be ideal since it would be liquid at room temperature and hence useful for powering cars and trucks. So a light-driven process for splitting water would be most useful combined with a process to reduce carbon into liquid hydrocarbon molecules.
It seems to me that the best thing to do with H produced from solar energy would be to burn it for power where it is produced. Keep enough in tanks to run the generators overnight. Or even for a few days if the average sunlight statistic indicates that would be sensible.
Large solar installations of any type are likely to be in lightly populated areas anyway. That is where land is cheapest. And a good place for electrical generators too.
The above is predicated upon Solar to H to Electricity proving cheaper than PVSolar or ThermalSolar. That seems unlikely but facts will tell. And, as noted above, H is by definition available at night whereas PV and Thermal must either shutdown or add a workaround.
My guess is that this is doesn't look promising. It depends on titania absorbing light and releasing electrons, which means that it's just another form of PV - it's unlikely to be more efficient at producing electrons than other forms of PV, and unlikely to produce hydrogen more efficiently than standard electrolysis, so where's the advantage?
Perhaps titania is cheaper than traditional silicon PV, but PV is getting cheaper very fast....
But also there is significant progress on fast algae that have high oil content. The oil extracted from farmed algae can either be used to make liquid fuels, or else all of this kind of biomass can be directly burned in power plants instead of coal to make electricity:
But on the other hand, the total 2009 budget of the US Department of Energy is is only $26 billion, and this includes all activities, which is ridiculously low, considering the astronomical amounts we are wasting in Afghanistan and Iraq:
If we get out of Iraq, then that money should be allocated immediately to the Department of Energy: Make that budget $125 billion per year.
Iraq is doing just fine, thank you. Or actually, no thanks to you and your ilk.
If you actually want cheap energy, read the site www.focusfusion.org . Development and initial implementation costs there are a few $million. Target implementation 5-6 years. Power at $0.001/kwh.
I don,t know what rock you have been living under,but hydrogen was used in the first internal combustion engine before they invented gasoline. plans for browns gas or hydrogen from water are all over the net. I have seen a working model you could build in a day. so I dont know who would pay money for a plan ,when it,s already on the net FREE jonno
If the one can make use of kind of material similar to TiO2 but in addition has capability of absorbing visible light then such systems will be very useful
I doubt that the hydrogen produced can be put directly into fuel for steam-turbine carnot-cycle and have the same or better efficiency as solar panels. The allure of hydrogen is its portability. It's a very good fuel per unit mass. If this company can make ethanol into a better fuel, we might have just found a cure in the energy crisis. Less corn, more power. Har ho ho har ho.