Volumetric energy density in watthours per liter:
Gasoline....9000 Wh/l
LNG.........7216 Wh/l
Propane.....6600 Wh/l
Ethanol.....6100 Wh/l
Liquid H2...2600 Wh/l
150 Bar H2...405 Wh/l
"..you do have to consider the contained weight of an energy delivery system. A gas tank adds relatively little weight to the gasoline it contains. But it is enormously unlikely you would be able to contain an equivalent 13 pounds of hydrogen in any 26 pound tank. Thus, the real-world contained energy density of hydrogen by weight is typically a lot worse than gasoline.
On the volumetric side, the hydrogen news is worse than all bad. STP hydrogen gas is laughingly pathetic. 2.7 watt hours per liter recoverable as electricity, or 3.3 watt hours per liter as heat. After compression and containment losses, ultra cold cryogenic liquid hydrogen has around one-fifth the energy density of gasoline.
Curiously, there is more hydrogen in one gallon of gasoline than there is in a gallon of liquid hydrogen. This happens because gasoline is denser by more than its hydrogen mole fraction.
At first glance, hydrogen would seem to have some things going for it as an alternate energy resource. Hydrogen burned in oxygen forms only water vapor. Which is a relatively benign pollutant. But when hydrogen is burned in air, more noxious oxides of nitrogen can also result.
In a typical situation, electrolysis takes two or more kilowatt hours of electricity worth ten cents each and converts them into one or fewer kilowatt hours of hydrogen worth less than a penny each. And that is before any fully burdened cost accounting, amortization, storage or processing. Thus... Electrolysis for bulk hydrogen energy is pretty much the same as 1:1 converting US dollars into Mexican Pesos.
At its very best, electrolysis introduces a staggering loss of exergy that dramatically reduces the quantity and value of transformed kilowatt hours of energy. Electrolysis is thus wildly unsuitable when driven from high value electrical sources such as retail grid electricity or any small scale photovoltaics."
Don Lancaster is compares gasoline tanks with tanks holding hydrogen in gas form. Then he shows the energy lose when dealing with hydrogen in liquid form. Both of these arguments are very valid and have held back hydrogen use in vehicles. But the beauty with United Nuclear’s fuel system is that the hydrogen is chemically bonded to hydrides. There is no seepage, and the research is moving very fast on improving the hydride storage system. For example: sodium aluminum hydride, also known as sodium alanate, has the potential to store (bond) more hydrogen then can be stored in liquid form.
Many people continue to point out that it cost energy to produce hydrogen, yes, this is true, but doesn’t it cost energy to explore for oil, drill, pump, ship, refine, store and sell gasoline. It seems ridiculous to shoot down the idea when the technology is moving so fast, just because there is cost involved. There are cost built into everything, but we don’t move forward by sticking our heads in the sand.
Don Lancaster worked very hard and put together some fine research, but technology is passing by him. He must have a look at the hydride storage system because it reduces much of the waste and cost he deplores in the hydrogen system. Think about the cost savings (energy savings) by producing hydrogen at your home, i.e., exploring for oil, drilling, pumping, shipping, refining, storing, gasoline tax, complications in the mid-east and selling gasoline.
It will not be free, but nothing is.
Holtz
JeffersonRepublic.com