You are currently viewing SemiWiki as a guest which gives you limited access to the site. To view blog comments and experience other SemiWiki features you must be a registered member. Registration is fast, simple, and absolutely free so please, join our community today!
Although not semi technology, this could radically change the semi landscape in everything from planes, cars, potable devices and anything needing energy storage. It could also change our whole electric grid that our society and industry is based on. It seems in small devices semi fabrication techniques could come into play and advance this technology even more. Comments, thoughts, observations wanted.
I think it could be a good propositions for automotive applications as it provides longer duration of storage. However it may not be suited for mobile phones because vapor discharge may not be desirable from smartphones.
Dan, it isn't the fuel cell that's the big deal, it's how they store the hydrogen. This is what's revolutionary. This is what will make electric cars viable and convert intermittent wind and solar to a steady reliable power source. The weight at one tenth of batteries and more viable than compressed hydrogen is the key.
The major cost in Hydrogen fuel is the containment, but containers come down in cost relatively as they get bigger since there is a ratio of surface area to volume that comes into play.
If Hydrogen was a viable fuel you should see it in larger vehicles first - e.g. ships and aircraft - and smaller vehicles last - cars. Also the energy density for pressurized (gas) H2 systems isn't much better than Li-Ion batteries - and you can just charge them at home.
The only application I can see working in the near term is intercontinental air travel using liquid H2 as fuel instead of kerosene - the liquid H2 can be stored in very large tanks at airports, and aircraft only fueled at the last minute so that (low pressure) cryogenic tanks are used instead of high pressure tanks, and you get the better energy density.
The problem is that hydrogen isn't really a fuel, it's an energy storage medium -- it has to be generated from something (water, hydrocarbons) using energy from somewhere (fossil fuels, nuclear, renewables) and then converted back to electricity (fuel cell) and used to drive something (electric motor). Unfortunately the efficiency of this whole process is pretty lousy, considerably worse than using batteries, and -- if the energy source is fossil fuels -- less efficient than just burning said fuels in a diesel engine. And don't even think about burning the hydrogen in an IC engine, this is far worse still.
So for anything that consumes a lot of energy -- cars, planes -- it's a pretty poor solution which just costs more and makes global warming worse.
For things which consume a small amount of energy -- phones, laptops, like the original posting -- it could make sense since the energy density is higher than current batteries, so long as the storage problems can be solved. But their blurb about high-efficiency is bullsh*t, it ignores the inefficiency of generating the hydrogen in the first place, never mind the cost of storing it -- compared to batteries the overall efficiency is terrible.
- that's a simple process that gives you Hydrogen on demand, so no major containment required, fully recyclable. Last I heard someone is trying to commercialize it.
Making Hydrogen then transporting it doesn't make sense.
"FCVs are more energy efficient than gasoline-powered vehicles. A fuel cell uses about 40 to 60 percent of the available energy in hydrogen. Internal combustion engines use only about 20 percent of the energy available in gasoline, although this is expected to improve over the long term.[16] EVs are more efficient than FCVs, using about 75 percent of available energy from the batteries.[17]"
Now add the inefficiencies in generating the hydrogen in the first place, and battery vehicles have much better grid-to-wheel efficiency than fuel cells -- which is what I said
All this says is that they've raised the throughput rate of hydrogen generation. The lower efficiency of a (power grid -- hydrogen -- fuel cell -- electric motor) system compared to (power grid -- battery -- electric motor) is a matter of basic physics, no amount of tinkering can close the gap. Even if the power comes from renewables, a fuel-cell based system consumes at least 50% more energy -- and since the issue with renewables is getting enough capacity in the first place, using it efficiently is critical.
- that's a simple process that gives you Hydrogen on demand, so no major containment required, fully recyclable. Last I heard someone is trying to commercialize it.
Making Hydrogen then transporting it doesn't make sense.
Exactly the same issue as all the others -- what's the overall cycle efficiency? Bet you [insert amount of your choice here] it's a lot lower than BEVs...
If the world wants to reduce CO2 emissions by switching to renewables, the first priority is to make efficient use of the power generated by them since their density is so low. Anything which wastes a big chunk of this due to inefficiency is a non-starter.
All the "hydrogen economy" proponents say how much better their system is than IC engines burning fossil fuel, while carefully ignoring how much less efficient they are than batteries. Yes of course there are issues with BEVs (range, refuelling time, grid loading), but given scarce and expensive power from renewables if we dump fossil fuels, they're the best solution to the transport problem.
- LITTLE ENGINEERING GIANT - Brunel observed that if (air/water) resistance is a square law and size/volume is a cube law then for a given % of load given to fuel, bigger vehicles go further - so he built very big ships to get across the Atlantic under steam power. Physics hasn't changed since his day.
The lower efficiency of a (power grid -- hydrogen -- fuel cell -- electric motor) system compared to (power grid -- battery -- electric motor) is a matter of basic physics
Not all research for hydrogen tech is on this cycle. You have direct solar -- hydrogen cycle avoiding the low-efficiency (<20%) solar -- electricity cycle. Or fuel cells running on natural gas maybe combining heating your house with loading your car batteries in a heat-power cogeneration system.
Not all research for hydrogen tech is on this cycle. You have direct solar -- hydrogen cycle avoiding the low-efficiency (<20%) solar -- electricity cycle. Or fuel cells running on natural gas maybe combining heating your house with loading your car batteries in a heat-power cogeneration system.
I agree that if you consider things like CHP the picture might change -- but then CHP has been proposed for many years and it is still only a minute fraction of energy usage/generation because it just doesn't fit with where and when the heat and power are needed (but this could change with mass adoption of battery power storage, combining home and car resources). If there was a high efficiency solar-hydrogen cycle (is there?) the picture could change again.
But almost everyone pushing "the hydrogen economy" is just ignoring the overall efficiency issue, this is the point I was making.
