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Why fuel cell cars don't work

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Re: Why fuel cell cars don't work

#161

Post by crimsonalucard »

D_Alex wrote: post #131
crimsonalucard wrote: post #11

Earlier quoted context omitted.

There is no excess. Renewables do not have anywhere near the capacity to charge a fuel cell automobile economy. Additionally, if there was capacity why not use it to charge lithium batteries?

>There is no excess ...yet. But solar and wind power are becoming the cheapest way to generate electricity. Their naturally variable production will mean that there will be periods of excess power available, and finding a good use for that excess would be nice. But I agree that batteries, not hydrogen, are the way to go.

When you factor in all the sources of energy consumed in this country, captured solar power amounts to well less than 1 quadrillion Btu out of an annual total of 96.5 quadrillion.

There will never be an excess of solar or wind. Even if you continue the dramatic growth in renewables of the past decade there is utterly no chance that renewables can replace fossil fuels. The gap is too great.

You are living in a dreamworld if you think that the path to a sustainable future can be found through technology alone. Sustainability can only be achieved by dramatically lowering our energy consumption rate.

Re: Why fuel cell cars don't work

#162

Post by darkmighty »

kylebrown wrote: post #156
schiffern wrote: post #132

Earlier quoted context omitted.

Here's the dirty little secret of the "hydrogen economy": it's a fossil fuel bait-and-switch. Renewable hydrogen from water is 2-3x as expensive as making it from natural gas†. It simply can't compete at the pump. People won't pay $9/gal equivalent when $3/gal is available right across the street (or across town, for that matter). † releasing just as much CO2 and fugitive methane, and still being wholly unsustainable

The question isn't, "what's the cheapest fuel at the moment?" The question is what's the cheapest carbon-neutral power source that could scale up to meet future global demand? Daniel Nocera has been arguing for years that using solar energy to split water into hydrogen (ie. the "artifical leaf") is the best strategy. Not even nuclear can scale to meet global demand[1]. But solar devices can be mass manufactured and d…

If a 'artificial leaf -> fuel cell -> power' is less efficient than 'photovoltaic cell -> battery -> power' and the cost is comparable, I don't see how your point is valid.

Yes, we'll need a lot of energy, but note that that figure is for the whole world. I think it's doable. Hell, it's the best alternative so 'doability' doesn't really matter, but I guess we'll see how close we'll get (with nuclear+solar). Note that china alone has 200 nuclear plants in project right now [1].

[1] http://nextbigfuture.com/2015/02/china-could-build-200-nucle...

Re: Why fuel cell cars don't work

#164

Post by baddox »

darkmighty wrote: post #162
kylebrown wrote: post #156

Earlier quoted context omitted.

The question isn't, "what's the cheapest fuel at the moment?" The question is what's the cheapest carbon-neutral power source that could scale up to meet future global demand? Daniel Nocera has been arguing for years that using solar energy to split water into hydrogen (ie. the "artifical leaf") is the best strategy. Not even nuclear can scale to meet global demand[1]. But solar devices can be mass manufactured and d…

If a 'artificial leaf -> fuel cell -> power' is less efficient than 'photovoltaic cell -> battery -> power' and the cost is comparable, I don't see how your point is valid. Yes, we'll need a lot of energy, but note that that figure is for the whole world . I think it's doable. Hell, it's the best alternative so 'doability' doesn't really matter, but I guess we'll see how close we'll get (with nuclear+solar). Note tha…

It depends how you're calculating efficiency. If you're talking about solar input to usable output, I contend that efficiency doesn't actually matter that much (at least until we start using a sizable portion of Earth's solar input). What matters more is dollars per watt. Last I checked (several years ago), simple solar heat engines were considerably cheaper per watt than photovoltaics (for generating electricity), even though photovoltaics were considerably more efficient by the former metric.

Re: Why fuel cell cars don't work

#165

Post by canberroid »

vacri wrote: post #146
greglindahl wrote: post #87

Earlier quoted context omitted.

Lots of people who have yet to own an electric car think like you do. People who've tried it and have home chargers discover: 1) It's really nice that your car is fully charged every morning... sure beats having to visit gas stations on a regular basis. 4 hours is not a big deal if you're asleep. 2) If you want to go long distance, a network like Tesla's supercharger does the trick. (Tesla owners drive SF-LA by stopp…

and have home chargers This is an incredibly significant point that continuously gets glossed over in these pro v con lists. I park my car on the street, and that's not particularly uncommon. Should I run an extension cable over the footpath? What if I have to park further away than my cable reaches?

I would run some underground conduit to a box in the ground by the road with ~10m of extra extension cable in the box.

Re: Why fuel cell cars don't work

#166

Post by tarikjn »

Refilling and storage issues are being worked on by using ethanol instead of H2 (look up Direct Alcohol Fuel Cell). It is considered better than methanol due to a much lower toxicity and higher energy density but the tech is just not there yet. This is considered to be the future for medium size batteries (small vehicles, hand machinery etc.).

Beyond that, what is wrong with green crude-derived fuels (gasoline, diesel, jet fuel) as a medium of energy storage?

It is being produced right now in small quantities after refining green crude made from algae grown into water/sunlight (carbon neutral form).

Some advantages:

  * doesn't compete with arable land like corn ethanol
  * can be grown in salt water
  * no oxygen atoms to oxide your tank/engine
  * much less sulfurs or combustion by-products than fossil-crude refined fuels
  * can be refined using existing infrastructure
  * can be distributed using existing infrastructure
  * can be used in existing vehicles and machinery
  * recycling combustion engines is much less energy-intensive than batteries

Re: Why fuel cell cars don't work

#167

Post by demultiplexer »

jgamman wrote: post #102

ex-FC researcher here. pretty much gets it. some other context: it's hydrogen for cars because of the chemistry ie, start-up, shut-down and response times. most FC claims are more of a 'displaced emmissions' scheme than zero-emmissions (unless you're in say, NZ where we have @#$# loads of renewables on our grid). PEM fuel cells are limited to 100 dC due to the hydrogen ion transport via liquid water - that's a proble…

(writer of the blog post here) Interesting, can you divulge a bit more about where and when you did FC research? Was it academic or for a manufacturer?

You are absolutely right; PEM FCs - and I glossed over this in the blog post, might want to readdress it in a future part - are the only portable-enough technology for fuel cells and they inherently come with this ion transport problem and by extension cooling problem that is just unsolvable. Which is essentially the root cause of the complexity of an FCV.

Anyway, I feel your jadedness. Until I actually worked with fuel cells, I had absolutely no idea. Nobody had adequately conveyed to me how these things work and what goes into actually building FCVs. Things finally started to click in my head when we had an electric kart on batteries done within days after completing the frame, yet it took many months until the fuel cell worked. And this was a pretty ready-to-go fuel cell in most respects (Hydrogenics HyPM8).

I was too young back then to appreciate how long FC tech has been 'just around the corner' in the media. Now I understand. I built an FCV 7 1/2 years ago! And they're still pretty much at the same point. I wish things were different because I love the tech, but nature wins this time.

Re: Why fuel cell cars don't work

#168

Post by demultiplexer »

r00fus wrote: post #5

The article deftly steps around the real issue: Fuel Cells are entirely an petroleum industry promotion. The goal is to provide a seemingly credible (but in reality completely unworkable) clean alternative so politicians, car companies and oil companies together can work "towards a clean future" while deep down knowing that it's a stalling tactic to keep the petroleum infrastructure in place. Any fuel cell funding su…

(writer of the blog here): Eh... hm.... I really don't want to get into conspiracy theories here. To be honest, during the whole Formula Zero championship we got absolutely zero interest from any fossil fuel companies. I haven't posted a good picture of our kart yet, but our biggest sponsors? - Greenchoice (a grid energy provider with a focus on renewables) - DSM (plastics manufacturer, mostly because of our innovative use of composite body parts) - University of Delft - A whole bunch of mechanical suppliers (Rodac, Swagelok) - A whole bunch of electronics suppliers (Chroma, Cyner, Betronic) - A logistics company (van Kaathoven)

Even the organization of Formula Zero, who had a pretty strong foothold in the fossil business through their renewables programmes, didn't get any attention from fossil fuel anything.

And this barely changed when the competition dissolved into Formula Student. Even though this is one of the biggest student competitions in the world, it doesn't get nearly as much sponsorship from big oil as e.g. the Shell Ecomarathon. If they were really interested in getting enthusiastic, almost evangelistic people on the case to promote hydrogen as the next big thing, they would sponsor Formula Student.

Re: Why fuel cell cars don't work

#169

Post by demultiplexer »

jessaustin wrote: post #39

The picture of their race-car surprised me. The driver's seat is right next to, and seemingly unshielded from, a stack of 36 "very large ultracapacitors". Are these less likely to explode than other capacitors? Sure they might have electronics designed to keep them within safe operating margins, but for safety I'd trust distance and enclosure more than custom electronics.

It's a... student project ;)

However, the actual amount of energy in those ultracaps isn't that much. We're talking a couple tens of kWs or, in other words, all those caps together don't even hold the same energy as one single li-ion cell (18650 size). The energy density is low, thus, the actual safety issue is fairly minor.

That being said, they are in a special Nylon enclosure with polycarbonate sides which provides an effective shield in the case of rupture. But, at the moment that picture was shot we hadn't actually tested that yet :D

Again, students.

Re: Why fuel cell cars don't work

#170

Post by demultiplexer »

smegel wrote: post #47

Why "hydrogen" fuel cell cars don't work. Quite the misleading title.

(author here): this is part 1. I will go into other types of fuel cells in a future part. Hydrogen is the focus of the first two parts just because this is the most mature technology and has actually been used in a couple of (kinda..) production cars.
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