Saturday, August 3, 2013

A bursting bubble? - Hydrogen

Hydrogen - the mirage,

I'm beginning to see the conservative news machine and astroturf bloggers winding up for a go at electric cars. This makes sense as Big Oil needs to squeeze maximum dollars out of vast holdings that require fracking and pollution intensive methods for recovery.  Regardless of US security interests, world climate, etc. One of the darlings of this group is the hydrogen car. It is held out as 'the answer'. Why not - when it combines hydrogen and oxygen in a fuel cell - what do you get - good old safe non polluting water and electricity to power a vehicle.

That model also excites gas companies - liquid hydrogen can't be produced on your roof with solar cells or wind in the backyard. Electric utilities don't find it competing with their baseline load production like home solar and wind. Stations will just offer regular, unleaded, and liquid hydrogen. Centralized with the big companies selling the consumer 'what they need'. Taxed by the cold pint of course so legislators and oilmen turned politcos are just drooling at this well understood road revenue source.

My good workout friend Larry pointed out a desert solar plant for making liquid hydrogen. I'll grant you this is a positive - hydrogen cracking because the electrical cost to produce chilled compressed hydrogen from water doesn't make sense from an electric cost, but a giant desert solar source going to waste due to transmission costs. That works. You can truck it out on a hydrogen big rig - ok thats fair if you solve all issues with hydrogen storage. The energy density is nowhere near gas or lithium air. Still might work, uses seawater and desert, and very low enviro impact with no CO2 - which is great.

The overall efficiency of producing, compressing, and using the hydrogen in a fuel cell is 46.9%.  This is not much greater than the 40% efficiency of the Prius hybrid and well below the efficiency of a diesel hybrid.  Researchers at Massachusetts Institute Of Technology (MIT) have reported that diesel with hybrid is more green than hydrogen fuel cell vehicles. So this hydrogen production is best done at some kind of desert area where solar is wasted. Of course there are the various maintenance costs for the plant but still this is promising.

The physics for hydrogen make for a tough case for anything not zeppelin or big rig size. Huge tank and safety armor required. That's not optimum real world implementation - that's basic physics of hydrogen. To quote Elon Musk whose SpaceX runs resupply vehicles to dock with the International Space Station:

“You could take best case of a fuel cell, theoretically the best case, and it does not compete with lithium-ion cells today. And lithium-ion cells are far from their optimum.”

A pessimistic link:

Check out this video from Fully Charged about fuel cells - interesting and partly positive:

Some other sources on the problems with hydrogen:

On balance I'd say economical hydrogen without an increase in CO2 is going to take renewable non CO2 energy as in Larry's link to the seacoast desert solar plant, combined with hydrogen powered transport rigs. For use in large vehicles due to the tank size and corrosive maintenance involved with hydrogen. I don't see it in normal vehicles any time soon. Perhaps a Hummer? - which could please conservatives and monster truck enthusiasts alike.

Robert Llwellen in the Honda FCX *Video*

Don't get me wrong - I applaud Toyota saying they will have 50 to 100K dollar consumer hydrogen vehicles by 2015. I am a skeptic though and I'm curious if their rollout beats Tesla's consumer model 40K dollar family car.  Combined with minimal cargo space, fuel costs greater then gas, and immense maintenance issues will Toyota's new offering stand up to Tesla's battery powered one?

Even more reading:

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