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Tesla S vs. Toyota FCEV - who is the fool?

Just fell over this interesting article that compares the Tesla S with the Toyota fuel cell vehicle.

Fuel cells vs. Batteries - who is the fool?
https://www.dropbox.com/s/c38iim95tccgozu/FCEV-vs-BEV-who-is-the-fool.pdf

Weight and range seems to be a huge cost and customer issue for the Tesla.

I really like the Tesla but the new Toyota fuel cell vehicle also seems tempting, despite I can't buy one today.

This article on Bloomberg does not make the choise any easier:
http://www.bloomberg.com/news/2013-10-10/toyota-shows-hydrogen-prototype...

Should I buy a Tesla or wait for the Toyota - What do you think?

Herbert

Toyota has range of your city or less. Hydrogen infrastructure doesn't exist, electricity is everywhere. Also volume of the HFC system is much larger than pure BEV, so there is less space for you and your cargo, and HFC (current techs) deteriorate faster than batteries do. It's also way more complex making failures more likely.

I wouldn't mind having an EV with a FC range extender. That seems like a logical match since they're already EVs...

Why would you want a FC range reducer? It's just a pointless extra clutter in BEV.

Well, until the needed infrastructure is built out, I wouldn't. Assuming hydrogen was as ubiquitous as gas, the speed of fillup would be a good advantage.

Since hydrogen has such a low density, getting a useful mass into a pressure tank requires very high compression. Even without a spark a hydrogen tank is a bomb.

And for every fender bender you have to call in the bomb squad. California wants by 2050 half the vehicles to be Hydrogen...

They didn't mention cost of the fillup and general performance. That 100kW fuell cell will give you 100kW power but without any power buffering battery it will be much slower accelerating car than Model S.
They are comparing only stuff which is favorable for them... as usual :)

Also they did not compare it to Mr. Fusion, which, incidentally, is also coming out in 2015.

The hydrogen fuel cell (hfc) produces electricity, and as such, will also power an electric motor. I am not certain the general performance cannot be the same as a vehicle like Model S. When I acquired my truck in 2006, I though that my next vehicle would be an hfc powered vehicle, but it is still a long way off. The production and distribution of hydrogen is still too expensive and undeveloped to make this feasible in the near term.

The other small detail is the high pressure environment, which in view of the recent fire involving a piece of metal and a Model S makes the hfc less desirable. With the Model S, there was a warning and ample time to stop and get out. If something happens with an hfc vehicle, there will be now warning. At least with hfc you will not have to stand there watching your car burn... In fact it might be over before you realized something happened.

I don't want to go to a fueling station of any kind again.

I had to do the propane routine for a while. It is worse than a gas station. With an EV I have a fueling station in my garage that I don't have to worry about refilling.

Supercharger stations go in very quickly with minimal impact on the environment and the hosting communities reap great rewards.

@leonardD, it can be similar, but it would require FC three times as large as in the comparison making full system weight about 380kg, and that FC alone would be about as large as Model S batteries if not bigger. 380kg vs 600kg isn't that large difference anymore.

this is also interesting to note:

Most optimistic technology cost targets 2035+ available from literature

BEV-500km:
85kWh battery | €103/kWh
= 8755€

FCEV-500km:
100kW fuel cell | €30,5/kW
5 kg 70MPa H2 storage | €348,2/kg
2 kWh hybrid battery | €577,5/kWh

3* 100kW * 30.5€/kW = 9150€ (we want to compare apples with apples, right?)
5kg * 348,2€/kg = 1741€
2kWh * 577.5€/kWh = 1155€
= 12046€

@Timo, the energy use of the car isn't constant, so the car is really an electric car with a 2kWh battery - but has a 100kW fuel-cell generator that can charge the whole battery in just over 1 minute.

The Tesla can go from 0-60 in under 5 seconds, but you can assume that in most situations it doesn't then go 60-120 in the next 5 seconds, and 180 after 15 seconds. It's a 5 second burst of every ounce of power the battery can provide.

The 60kWh battery provides lower bursts of power, and a 2kWh battery would have great difficulty 1/6th of its whole charge in 5 seconds! Not to mention the damage to the battery. That's where an 'ultracapacitor' comes in (and that may be what the 2kWh battery is). If you need 300kW for 5 seconds then a 100kW Fuel Cell would need to charge for 15 seconds (and it'd need to be able to store the required capacity, and the fuel cell power would need to be exclusive - but I'm ignoring the regen breaking charging it too). Actually I can't remotely see what a 100kW fuel cell would be needed, it'd work with much smaller.

I'd prefer a battery future, with greater use of solar world wide, but even then it may turn out that if a battery can cover 95% of regular car usage, then adding a fuel cell makes everyone comfortable.

If you go with actual BEV/FC hybrid then smaller fuel cell would suffice quite well.

My main problem with FC cars are the space requirement for the total system. It's a lot larger than pure BEV. That's enough reason for it to be obsolete before it even gets started.

I don't know much about FC but I do remember one complaint for early adopters was that refueling took 30-45 minutes. If true, I'll keep my Teslas.

A fuel cell vehicle is an EV with an expensive, low energy density, low durability generator that uses (at this point) fossil fuel-based hydrogen.

Why not just generate hydro using cleaner power plants then store it in a high quality battery for use in an EV. Oh wait, we can do that now with the Roadster and the 'S... :-)

The other problem people don't talk about with hydrogen is it is very inefficient to crack water to generate it. Most hydrogen today comes from reforming methane. I think cracking water is up to around 50% efficient and hydrogen fuel cells that are useable in cars are in the 40% range of efficiency. That doesn't begin to discuss all the issues involved with hydrogen storage and embrittlement issues caused by it. H2 has a very low energy density. Lithium batteries are far more efficient.

Let's see, electricity -> crack water -> hydrogen -> fuel cell -> electricity vs electricity -> charge battery -> electricity.

Fuel cells are just a way to waste government research money.

Hi

I suspect the governments will force us to use an alternative fuel that they can tax.

The fact that you can generate your own electricity with solar/wind etc suggests this will not be the future of transport, at least not supplied directly by the user.

Hydrogen will need more infrastructure to make widely available and affordable thus will reuse the petrol/gas stations we all now and love/hate so that the fuel can be taxed efficiently.

Dec

Something I noticed missing from discussions and that is not a common metric to compare all these different versions of vehicles. At least so you can compare apples to apples in terms of cost. And this metric should make it easy to compare these costs. If I may suggest, MPG is almost obsolete here.

So how about this:
1) CPH (cost per hundred miles at 55mph)
2) CPM (cost per mile at 55mph)
3) CPF (cost per fillup)
3) MPF (miles per fillup at 55mph)

This would handle all variations, but in some cases you would have to be specific. E.G. CPM using hydrogen from methane is different from CPM from hydrogen made from water. CPM would also be different if you bought the hydrogen commercially at a station , or made it yourself, as in the Honda Clarity's system of home production of hydrogen from natural gas.

There is a lot of natural gas infrastructure in homes and even at commercial establishments should someone produce a a mass market natural gas to hydrogen system for commercial hydrogen stations.

Once you have an across the board comparison of costs, I still believe Pure EVs win handily.

*Also no one mentioned fog, are we trading smog for rush hour fog from tailpipe water vapor ? A pleasant side effect may include greener grass and plants in large arid cities from hydrogen fuel. Could that reduce carbon from more plant mass from the water vapor emissions ?

My first thought is that cost is too difficult a metric. You look up a car in 2016 and compare to 2013 and the cost of all (energy and petrol and hydrogen) has changed from 2013 to 2016 at different rates. What's more it's also different in different states, and countries, and you're talking about a US dollar based measurement.

At least MPG and KM/L can be converted by a formula - but not MPGe! They just compare electrity and gasoline prices anyway. And other countries have dramatically different prices here too. So maybe I'm wrong - we have no useful metric at present!

I see you're really suggesting an efficiency metric (that doesn't pretend to be related to gasoline). And a "range on one charge" that EVs already talk about very commonly.... but something that allows an easy comparison between hydrogen cars, EVs, .. and other cars?

It's a good goal, just not sure how possible it is. Is there a reason you suggest $ per mile, not miles per $? And could we remove "Miles" while we're there?

Maybe it would work as a formula though - make every car provide a miles-per-kW or miles-per-gallon etc, so we can put in the price and get a useful comparison. Then we can compare cars across countries and years, or get a cross comparison by using our current petrol/energy prices.

You should really start new threads for ideas like this, it's going off topic :)


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