Future of Cars: Hydrogen Fuel Cells, Or Electric?

cartechboy writes: "Back in 2010, Toyota and Tesla teamed up to develop electric cars. That partnership gave us the RAV4 EV electric crossover, but it seems as though that will be the only vehicle we see from that deal. The partnership will soon expire and Toyota has no plans to renew it. Why? Because Toyota believes the future is in hydrogen fuel cell cars, not battery electric vehicles. We knew trouble was brewing when the RAV4 EV failed to set the world on fire when it came to the sales floor. Then Toyota and Honda announced plans to debut hydrogen fuel cell vehicles as early as next year. Add it all together and the writing was on the wall. Is Toyota right? Are hydrogen fuel cell cars the future, or is it missing the mark?"

Re:Electric.

[Anonymous Coward]

Easy to top the energy wasted by burning a gallon of gas in a ICE and not even factoring out the pollution effects.

Re:Electric.

[ShanghaiBill]

Hard to top the energy density in a gallon of gas

You need to multiply the energy density times the efficiency. A gasoline burning ICE has an efficiency of about 15%, an electric motor is over 90%. After that, you will find that the gasoline still wins on range, but loses on cost (excluding the initial cost of the vehicle). Battery technology is improving faster than ICE technology, so is likely to eventually win, as the battery production costs come down and the range goes up.

   

Re:setting the world on fire

[mschuyler]

How many gasoline cars catch on fire every year? Thousands.

How many Teslas have caught on fire ever? Two

Conclusion: Teslas catch on fire.

Re:Diesel

[evilviper]

No alternative fuel even comes close to the reliability and availability of diesel engines

Electricity is both more reliable and more widely available than diesel fuel, by FAR.

Re:Electric.

[Carnivore]

I may be misinterpreting your statement, but Tesla uses AC induction motors with no permanent magnets and no rare earths.

Re:Electric.

[AaronW]

The problem with hydrogen is not just electrolysis being 80%. You lose another 20% just compressing the hydrogen. Then comes safety. Hydrogen leaks and tends to rise so parking a hydrogen vehicle indoors (i.e. a garage) is not safe. It is explosive under an extremely high range of mixtures. It burns with a nearly invisible flame. It can spontaneously combust. It embrittles metal. Unlike CNG you can't just add an odorant either since it will foul the fuel cell.

There is a hydrogen filling station in my local county for filling experimental HFC buses. They've already had one fire at the facility which is not used by the general public.

Hydrogen filling stations are also going to be far more expensive than gasoline stations. The equipment to generate hydrogen is very expensive. You can't transport hydrogen in the quantity needed by truck in a cost effective manner unlike gasoline and diesel and existing pipelines cannot be used due to embrittlement.

Look at how hard it is to stop all these gasoline engine fires. There's dozens every day. Gasoline doesn't spontaneously combust and requires a good spark or heat source to ignite it. It also is not explosive except under a rather limited range of mixtures. If hydrogen starts leaking in a garage it won't slowly combust like gasoline tends to do, if it ignites it will likely explode. With all those poorly maintained vehicles on the road how do you think things will fare with hydrogen? Unlike a gasoline car which only explodes in Hollywood movies, hydrogen is extremely explosive at a mixture between 4 and 74% in air. It will rise so it if leaks in an enclosed space it will rise to the ceiling. Hydrogen requires extremely little energy to ignight. It can spontaneously ignight from a leak or be ignited by sunlight.

Fuel cells are also only 42-53% efficient. Combine that with the losses from compressing the hydrogen (20% loss) and creating the hydrogen (25% loss under the best case). Also, almost all hydrogen manufactured today comes from natural gas and at least 20% is lost due to the endothermic reaction. You then have the same losses you would have with an electric vehicle and the losses of a battery, since HFC vehicles also need a battery for regenerative braking and to handle acceleration since the HFC will likely not handle peak load.

http://www.thenewatlantis.com/... [thenewatlantis.com]
While some things have improved since it was written, others have not and are limited by the laws of physics.

http://en.wikipedia.org/wiki/H... [wikipedia.org]

Re:Electric.

[sribe]

I think you'd be surprised. In urban driving, some some typical numbers would be engines about 40% efficient in terms of extracting energy from fuel...

Uhm, no. Maximum theoretical efficiency of a perfect (massless, frictionless) ICE at the compression ratios available in passenger cars is more like 35%. Actual efficiency doesn't top 85% - 90% of 35%, in other words, less than 30%.

Re:Electric.

[NeverVotedBush]

While hydrogen has a very high energy content by weight, it's tough to get much weight in a compact space. One way is compress the heck out of it which introduces pressure vessel requirements and high pressure gas liabilities. Compress it to a liquid and now you have cryogenic liquid issues, boil off, etc. Or use some kind of misch metal or other matrix to "dissolve" the hydrogen in except misch metal is very very heavy and pretty expensive. One other way of storing hydrogen is to store it in a chemical compound like a boron hydrate that you can reversibly remove it from for use and add it back for recharge. But all those are not nearly as simple as pumping a gallon of gas into a vented tank. But hydrogen generally does have range issues. It is hard to store a lot of it by weight in a small space.

Another issue with hydrogen is that it wrecks ozone and it moves easily into the upper atmosphere. It's not catalytic like chlorofluorocarbons, but get a few hundred million hydrogen vehicles refueling every week or three and even tiny little leaks will add up in the upper atmosphere and cream the ozone layer. It also doesn't help that hydrogen leaks out of metal fuel lines by dissolving and diffusing through the metal itself.

Garages and any kind of enclosed space would have to have special venting as well since hydrogen can pool on the ceiling if it escapes since it is lighter than air. Instead of floor drains in low places, there would have to be vents at high places to allow hydrogen a way out to prevent buildup.

It does have the advantage, however, of not pooling under a car and roasting the occupants if it catches fire. It goes up and dissipates very quickly. Also, hydrogen fires aren't loaded with carbon to make them incandescent and like raging radiant heaters. You can stand right next to a roaring hydrogen fire and barely feel it. Put a body part in the fire, however, and you'll feel it. But compared to gasoline, it's actually quite safe as far as fires are concerned. Hydrogen fires are also nearly invisible which can introduce another danger. When people look at fires like the Hindenburg, the dark billowing fire is because of the aluminum paint used to protect the fabric burning. It's not the hydrogen.

Re:Electric.

[uradu]

Here is a Wikipedia excerpt regarding modern turbo diesels, currently the most efficient automotive ICEs:

"Modern turbo-diesel engines are using electronically controlled, common-rail fuel injection, that increases the efficiency up to 50% with the help of geometrically variable turbo-charging system; this also increases the engines' torque at low engine speeds (1200-1800RPM)."

A 50% efficiency is pretty amazing and testament to over a century of dogged, steady improvement. We're approaching the theoretical maximum efficiency of the ICE.

Re:Electric.

[LinuxIsGarbage]

It's the charging time that's the problem. I make a 550 mile trip on a regular basis (work). I fly sometimes, and take the motorcycle sometimes, depending on weather and other factors. The bike has perhaps 200 miles capacity, so the Tesla already beats me on range. But the bike's refueling time is perhaps four minutes if I don't take a potty break. The tesla is what, six hours? That's turning a one day trip into two, both ways, unless I want to drive through the night.

Electric cars don't just need to get longer range. They also need to get significantly faster refueling times. For trips beyond the single charge range, there may never be a practical solution. (Yes, I've heard of the battery swap idea. I don't expect that to become widespread for a number of reasons.)

Check out Tesla Supercharger. Not quite 4 minutes, but 150 miles of range added in 30 minutes. Sit down for supper or a coffee break while it charges.

http://en.wikipedia.org/wiki/T... [wikipedia.org]

Re:Electric.

[anorlunda]

Line losses for electricity are in the 10% or greater range (the figure for Canada is almost 40% due to the amount of power we get from relatively remote hydroelectric facilities). So electricity and hydrogen aren't too far off-base with respect to losses.

I call bullshit. The losses are not that high.

From http://en.wikipedia.org/wiki/L... [wikipedia.org]

" For example, a 100 mile 765 kV line carrying 1000 MW of power can have losses of 1.1% to 0.5%. A 345 kV line carrying the same load across the same distance has losses of 4.2%. ... Transmission and distribution losses in the USA were estimated at 6.6% in 1997 and 6.5% in 2007"

I can tell you that most of those losses are in low voltage local distribution, not the long distance transmission.

You claim 40% losses from the remote hydro in Canada. James Bay alone makes 16 GW of power. 40% of that would be 8.4 GW. In order to dissipate that much power from those thin wires, the temperature of those wires would have to be hotter than the core of the sun, and it would warm up the transmission corridor to Miami Beach climate. That's nonsense.

Think of countries like Sweden and Brazil where the bulk of the power is generated thousands of miles from the consumers.
They operate without excessive losses.

Cite your sources dude.