Engaging Energy

A word to the wise – never be in London when there is a tube strike about to start, things get a bit crazy.
Anyway Day Two of the discussion meeting covered: Hydrogen storage, cerium oxide (for synfuels and hydrogen production), nuclear fission & fusion, more fuel cells, some super-capacitors and a bit of policy.

Interesting stuff that I noted down:

Zuttel
Each kWh provides €25c of full-cycle economic advantage while the current average cost to European consumers is about €5c/kWh.
The oil price spike in 2008 took those prices towards parity meaning, that no net economic advantage was effected by the energy expended, contributing in a large part to the economic crash.
I’d not heard it put in those terms before, and if there is a real and verifiable corelation between delta energy cost/benefit and the occurrence of economic crises, then we have a really powerful preventative tool. My guess is that this relationship is much less clear cut and that the materials scientist who proposed it isn’t fully up to speed on behavioural economics, but that’s only a guess.

Hydrogen carries 39kWh/kg

Recent regulations against the use of asbestos have effectively killed the prospects of using electrolysis of water as a large scale hydrogen production method in Europe. Asbestos was used in industrial electrolysis as a membrane.

Hydrogen storage tanks are now made of a thin blown aluminum shell, wrapped with kevlar or carbon fibre.
Hydrogen storage in metal hydrides can be twice the amount that can be held in tanks as the hydrogen is adsorbed onto the metal hydride in a very densely packed fashion. However, you need one metal hydride per hydrogen, so the storage media gets really heavy, really quickly as the tank size increases. There is an option to combine both hydride and liquid storage to get the best of both worlds.
Even with hydrogen stored in metal hydrides, the energy density is still only half that of gasoline.

Haile talked about ceria (cerium oxide) – a wonderful material apparently (she got her mineral economics all out of whack of course, but was better than most on the resources side).

Full cycle ceria-mediated synfuel production is currently 13% efficient, 23% efficient if you recover 50% of the process heat. The inputs are sunlight, water and CO2 as far as I can tell.

She quoted ceria availability at 40Mt – enough for >50,000 100MWe power plants operating 6hrs a day. Cost $140/MW installed using $20/kg of ceria. She didn’t mention that in Feb 2008 cerium price was $9.50/kg, so I will.
Cerium (for the uninitiated) is the least rare of the Rare Earth Elements (REEs), but that doesn’t mean that is is geologically more readily available than, for instance, lead which has a similar crustal abundance. The geochemistry of REEs means that there are very few deposits rich enough to be mined at a profit. Deposits are generally rich in either ‘light’ REEs or ‘heavy’ REEs, but not both. This limits a mine’s ability to fully service a customer with a mixed REE product, so limits its profitability. There are three main REE deposit types as far as I know; carbonitites (igneous intrusions such as that previously mined at Mountain Pass, California), ionic clays (where the REEs have been adsorbed onto clay minerals from groundwater) and REE-enriched iron ores. These last two are the forms seen in China, which currently provides 95%+ of the world’s REEs. Anyway, yes they may be relatively abundant, but they are not very available.

Grimes showed some nice animations on defect modeling in radiative environments.

Duffy talked on fusion. Apparently the bigger, the better with fusion (less losses through reduced surface area of the plasma per unit volume). ITER should be a net power producer giving up 10x the energy put in (50MW in – 500MW out), but it won’t be set up to extract that energy from the system because that isn’t what its for. It is primarily a materials test lab since the plasma physics is pretty much sorted (they think). The demo plant, to follow in 30 years or so, is sketched out to be a 3,000MW monster producing 50x energy input. First electricity to grid sometime after 2050.
For Paul; the fusion boys are not in the least worried about lithium availability for the tritium breeder jacket because there is ‘loads of it around’. As you know I tend to agree, lithium availability is energy price sensitive and not geologically constrained.
However other elements in the reactor vessel may be resource constrained – beryllium & tungsten specifically and they are looking at these very closely.

Hirose (a bit of a legend apparently, now works for Toyota Fuel Cells division)
The Japanese always have a different angle on things and it was fun to hear the debate between the Japanese view and the Californian when it came to transport availability. Hirose stresses the Quality of Mobility (QoM) and the role of fuel cells in maintaining or extending QoM, whereas Haile warned against generalisations of social conformity in development of scientific solutions. The point was actually raised several times that social science needs to be engaged in progressing societal change and the roll-out of these new technologies. I agree, why else would I be here ?

Toyota’s well to wheel efficiency for fuel cell vehicles using hydrogen is about 40%

Simon on Supercapacitors – ‘supercaps’ in the biz
They are a complimentary technology, not a disruptive one to batteries. They have a short discharge time ~10sec at high power, so have applications in acceleration of mass, quick deployment mechanisms and the like, but the most interesting applications were in energy harvesting from mechanical systems to time-shift that energy back into later acceleration. Effectively its the regenerative braking that is talked about in Formula One.
But you will never run transport just on supercaps, they just make the system more efficient, ~30% more efficient at present. Good news, but not a stand-alone solution.

Foxon was the only speaker to come in under time, brought no new data and was dull. I’m just all-round glad he’s not coming down to speak at our conference