A New Energy Storage Medium: X PRIZE

[Knucklepop]

Semi-Solid Lithium Rechargeable Flow Battery

Some progress.

[GreedIsYourGod]

Why was the prize for a device with "an energy storage density equal to or higher than gasoline?"

Environmentally benign, that I totally get! But I think you have chosen the wrong yardstick in saying that the replacement must be energy dense.

In my mind the best replacement would be that one that is the least expensive in dollar cost (and resource cost) per Joule stored.

I think a better goal would be to undercut both the dollar cost and environmental impact of gasoline.

[jib1000]

How would an energy storage unit replace gasoline? Gasoline is a source of energy. If you replace it with a battery, as you suggest, you just have to get your energy from somewhere else. You aren't fixing anything, just moving the pollution from the road to the power plant.

[luceneInAction]

@jib1000, energy storage would replace gasoline by storing power derived from sources other than gasoline. Sources such as the massive 200 to 500 MW solar plants that are scheduled to be constructed in California and the Southwest. Or the large wind farms being planned across the country. Even electricity generated from coal has a smaller carbon footprint that gasoline burned in an internal combustion engine. Internal combustion engines are incredibly inefficient.

[jib1000]

@luceneInAction True but solar is even more inefficient that gasoline, and wind power has a huge footprint that can never cope with the nations energy needs. Neither of these two sources of energy can replace the energy needs of all gas engines, not to mention the electricity needs of our country.

Coal and natural gas are slightly less polluting than gasoline, but if you are going to make some sort of battery, you'll have to use up resources making, maintaining, and disposing of them.

[justmesujoy]

Try hydrogen, its about 131MJ per Kg. ENJOY!!!

[Knucklepop]

@justmesujoy Close. Liquid Hydrogen: 143MJ/kg, or more importantly: 10.1 MJ/L

10.1 MJ/L is significantly less than gasoline and most other liquid fuels. On top of that, maintaining Liquid H requires intensive cooling.

If you had said Mr. Fusion I'd be on board :)

[justmesujoy]

@Knucklepop Just that actually! Engines did not replace horses nor did petrol replace grass but the car as a whole replaced the horse and buggy. There is no single solution to the energy and climate problem, the solution lies in the effective utilization of the solution. You cell phone battery recharges in about 30 minutes so could your car's battery. It will take advancement in different technologies and more importantly a change in attitude.

[primophysico]

While synthesis of Ethanol from atmospheric CO2 and electrolyzed H20 would drastically reduce the carbon contribution of the fuel, the costs of these processes seem prohibitive. Wind power is currently and will likely remain one of the most costly forms of energy (due to up-front costs) and electrolysis is a terribly inefficient process due to the loss of heat generated by resistance. Ethanol of course is also about 2/3 as energy dense as gasoline and therefore cannot be used by all engines.

[GlennDoty]

If you take industry exhaust - rather than atmospheric CO2, the environmental effect is the same, and the cost is much less.

High pressure electrolysis efficiencies: ~80% HHV (further processes use that heat, the energy isn't wasted).

RFTS efficiency ~80%.

Wind is by-far cheapest renewable energy source (~$0.03/kWh in good locations).

Total system efficiency ~60%, total energy expense ~$0.05/kWh.

We can make gasoline, ethanol is more profitable.

The market rules everything.

:)

[GlennDoty]

Why must this have a greater energy density than gasoline? Gasoline does pretty well, if someone came up with a truly carbon-neutral gasoline... that should be fine. For that matter, carbon-neutral ethanol should be fine... The key is making something that can scale to market demand and be used in today's technology. Right now, the only chemicals that fit your (per mass) energy density are hydrogen and methane, which are useless as energy storage. Better to focus on costs.

(IMO)

:)

[primophysico]

Gasoline is indeed a very efficient fuel source (which is probably why it was chosen as a reference), but one of the points made in this video is that the new fuel source must compete with gasoline. Competition requires undercutting your competitors and so a more energy dense and more improved fuel for this competition would seem to be warranted. The video also makes no explicit reference to chemical fuels and leaves open the entry to solid state storage such as batteries and capacitors.

[primophysico]

Glenn...Just a note on the science: Carbon-neutral ethanol has been shown theoretically to be nearly an imposible achievement in the purest sense of "carbon-neutral".

[GlennDoty]

Nonsense. Biofuels aren't carbon-neutral, that doesn't mean that ethanol can't be.

Biofuels from new fields are actually more carbon emittive than any other fuel source, they are horrible, and contribute to the food shortage that is starving the Earth... You don't have to convince me there!

We're working on chemically reducing CO2 to CO, electrolyzing water for H2 and O2, and using the CO and H2 in an FTS process to make ethanol-all using wind energy.

Pure carbon-neutral "WindFuels".

:)