The Economist: Electric cars Difference Engine: Tailpipe truths

H2 is only more efficient, tank to wheels. In doing so you you ignore the "charging loss", i.e. if you look at kWh from the wall, with your own h2 station, you've be looking at more than 2x the energy usage of a BEV.

Oh and the 5% you mention is over he 2005 FCX Fuel Cell, nothing on the chart you pointed to shows a BEV.. The efficiency gains over a BEV can actually be larger (because of weight needed for say a 200mile BEV battery), but just tank-to-wheels efficiency is misleading eitherway.

 

Somehow this discussion has gotten over the deep end, wait I know its proxi's notion. Hydrogen from reforming natural gas can be more efficient than simple turbine peak power plant supplying elecricity from the plant fueling an ev. Fuel cells might also be a way to buffer grid power during low demand, and DOE is continuing funding fuel cell research here.

The likely fuel cell vehicle is a serial phev with both a plug into the grid and fuel cells for longer trips. This means that to get to affordable fuel cell cars first we need affordable phevs. This is behind the shift from freedom car to plug ins. Germany still has a large fuel cell program and that will likely be a good test to see if vehicle prices actually can come down. That bmw liquid hydrogen 7 gets about 1/10th the distance of a clarity per pound of hydrogen, but you get a bmw7 for a much lower price than a clarity because you don't need to buy the fuel cells its burned in a 12 cylinder ice.

It will always be more efficient to store renewable electricity in batteries than fuel cells.

 

Hydrogen is more efficient at EVERY stage due to the HUGE energy density advantage it has over every fuel and fuel storage medium.

This basis in physics and chemistry is why Hydrogen always comes out ahead.

There seems to be a misconception about power generation, in all power plants (nuclear, gas, oil) the power is generated via STEAM turbines, heat is created to create steam to drive generators to create electricity. Not really efficient. It is correct to consider the steam generation as the hydrogen generation in plant build to generate hydrogen. So the energy efficiency of fuel-fuel is best for direct hydrogen production.

In wind, solar and hydro where there is direct generation of electricity, there would be some advantage for electricity but that gets lost in transmission and storage. The most efficient batteries are really inefficient vs. direct fuel like hydrogen.

Again, it's the basic physics and chemistry, the massive energy advantage of hydrogen that always leads back to it as the ultimate fuel.

And that leads back to the real world application in vehicles which leads back to the Honda FCX prototypes, the actual use, actual efficiencies and advantages over battery powered vehicles.

 

The direct burn is really the way to go. The fuel cell and batteries both are expensive and hard to manufacture.

Direct burn requires little change to the vehicle or the supporting infrastructure. They hydrogen pumps in LA are right next to the gasoline pump. The fuel storage in the car is moving faster than battery technology so the range issue is diminishing quickly. The industrial gas existing infrastructure including existing long distance hydrogen pipelines all argue for hydrogen.

Consider that BPA is shutting down wind power because of TOO MUCH POWER generation. This surplus could be used for hydrogen generation.

 

But, even with an ice you need those batteries and motors to make it worhwhile. Than hydrogen bmw7 gets about 6 mpge. In order to be efficient it needs a big battery, think of the effieicy of a the prius phv. In 10 years that battery premium on a prius phv will be about $1500, hydrogen is about $7 for the equivalent of a gallon. The numbers never work better for hydrogen unless its in a plug in hybrid.

You still need that expensive hydrogen tank and refueling infrastructure. We have a plug in hydrogen bus and fuelling station here. Germany is going to build the infrastructure. No reason for the US to spend the money for the test. The US is rich in natural gas and can produce fossil fuel hydrogen cheaper than germany, but plug in hybrid cng seems much easier and cheper to build especially for long haul trucks and local and long range busses.

Its the grid operators not the EPA. This can be alleviated by building out the grid better as texas is now doing. Fuel cell buffering mainly can help the grid by buffering night demand and using it during peaks or for fuel. The big waste plants are the base load ones coal and nuclaer, but even natural gas benefits by fuel cell technology.

 

Sorry, but only BMW is trying liquid and as I pointed out.. if you let the car sit for 10-12 days the tank is empty. How is that "practical"? Though I did give one idea.. it may be better for a PHEV if the costs are really lower or its more efficient, though for now I think BMW did it to prove the could..

Honda is compressed Honda Worldwide | Fuel Cell
Ford is compressed. Ford Focus FCV - Hydrogen Fuel Cell Vehicles
GM is compressed...

Here is a quote from
Automakers Chase Energy Storage for Fuel Cell Cars | CleanTechies Blog - CleanTechies.com

Only measured by weight.. not by volume nor by weight if one includes the necessary storage materials.

And its not really storage if one has to allow it to vent off and in a week or two there is none left.

Sorry, but the fact they are on the road does not make them efficient or cost effective. Its a research fleet to see what they can learn, to get them green credits for CARB and to get them some press.

I can live with expensive but right now the H2 fuel cycle is inefficient compared to battery. Maybe in a decade or two costs will come down, but that does not solve the energy inefficiency.

Making/Storing H2 efficiently is not trivial. There are some interesting ideas for making it more efficient, e.g. co-generation process. I hope you realize that the honda home-generation station converts Natural-gas to H2 and outputs electricity, not using electricity to produce h2. On the other hand the overall NG->h2+heat+ electricity may be more efficient than a power play using that same NG to generate electricity then the generating H2 and then compressing it.



Long term, we need to keep investing in R&D to find better ways to generate and store H2. By focusing on what we can do not HE, EREV, BEV), we can move more quickly to reduce oil dependence. As I said H2 is only needed for longer trips, so once we are largely EREV and BEV, changing the fuel source is much easier.

 

The beemer hydrogen demo uses liquid because it can store more in a tank that size, it burns a great deal of hydrogen and couldn't fit a bigger tank. Its rather simple. PHEV hydrogen ice or cng/hydrogen ice may be a first step. there is a lot more cng infrastructure and cng is happy in hydrogen tanks.

If you notice bmw is putting a great deal of resources on bev, phev, and hv right now and did not want to waste them on fuel cells. The ones pushing hydrogen right now are honda, toyota, and hydundai and they get large subsidies to do it from their governments. bmw, mercedes, and vw group will also play because of german government mandates. It doesn't mean its a promising technology, just that the governments decided it was one. The US pushed it at one point, but pivoted to plug ins. IMHO the money the US and california government spent on fuel cell cars was simply flushed down the toilet, like the gsa boon doggle in vegas. The fuel cell for fixed storage on the grid may bear fruit, and that would be enough to develop fuel cell technology.

 

Hydrogen is only 'energy dense' if you fail to add how much energy gets wasted in distilling it ... and pumping up to 5,000 psi, etc. Factor all the loss, and it's a hugely different story. For explainations, our own evnut here on PC has a nice read, with links:

Fuel Cell Vehicles

.

 

Hill,

Just so you argue this correctly in the future: Hydrogen is energy dense in energy per kg. Gasoline is more dense in energy per liter. Hydrogen loses that energy density argument in energy per kg when the weight of the tanks is added. Batteries will lose out on both matters, but are the most energy efficient for delivering renewable energy. FOr long range PHEVs are the most efficient, and hydrogen may be a good fuel, but it is only made efficiently from natural gas, which begs the question why not make it a gasoline or cng phev. A CNG structure is much less expensive than hydrogen, only needing compresion. Hydrogen needs to be both produced and compressed. To do this renewably is immensely expensive as indicated by your link over $100 per gallon of gas equivalent.

 

Direct burn means no batteries. It doesn't take a lot of modification to convert a gasoline internal combustion engine to a hydrogen internal combustion engine.

The manufacturing base is already in place.

"MPG" doesn't really work for hydrogen. Gallon is a volume measure not an energy measure. The issue comes up in storage as you need twice the volume at current technology for hydrogen vs. gasoline. We can make the car bigger because the fuel itself weighs less, there's no penalty to the bigger tank.

With hydrogen its FLAME ON.

No more expensive than gasoline in all respects as the current hydrogen pumps at various gas stations demonstrate.

It's all in the math, physics, chemistry....every time you do the end to end calc, hydrogen wins because of its huge energy density advantage. Added to its non-polluting aspect, it is the best transport fuel. Russians even made a jetliner burning hydrogen fuel.

 

Pretty good summary. What about a CNG fuel-cell range extender? That way you get increased efficiency from the fuel cell (50-60%) and no noisy, vibrating ICE to disrupt the EV motoring experience. If someone can figure out how to build a tiny CCGT turbine with the same efficiency we'd have a winner. Even a single-stage gas turbine with 40% efficiency would work.

Still run into issues of cost, weight and volume, though.

 

That is not the experience of BMW or Honda in building actual hydrogen powered cars.

See the links above to both sites.

 

The comment was about MPGe note the e.. its energy equivalent and the BMW 7 which gets about 4.7miles per gallon of hydrogen, is about 18MPGe.. Its pathetic in how inefficiently it uses the energy in that fuel. Fuel cells are way more efficient use of the FCX is about 60MPGe.
(see Two Hydrogen Cars

Price at the pump may reflect subsidies.. not actual costs. People want to promote it. Otherwise I'd conclude electricity is free since the local charging station is free.

Talk about the math, physics and chem all you want. It takes engineering to make things into viable products and that is when one looks at how to produce/store/transport and also consideres things like efficiency and cost.

 

This is incorrect. The doe used mpge and gallon equivalents so we can compare fuel sources. One kilogram of hydrogen has about the same energy as one gallon of gasoline. We can then compare them. If the bmw 7 hydrogen uses about 1 kg for every 16 miles it gets 16 mpge. Put a 4 cylinder turbo engine on a phev and the mpge shoots up a great deal

The hydrogen tanks are expensive. honda is going with 5000psi tanks because they are cheaper. Toyota is going with 10000psi tanks to get the volume low enough. CNG conversions use 3600psi tanks, which are much less expensive, but still the civic cng is much more expensive than the civic that runs on gasoline.

IIRC hydrogen is about $8/kg or gallon equivalent. These test stations subsidize the hydrogen. As hills link said, the renewable station in Sacramento actually has a cost to the government of over $1000/kg. Hydrogen from natural gas costs about 4x more than the natural gas itself, and this is the least expensive method of production. With better technology we might be able to reduce this to twice the cost

The only way hydrogen wins with today's technology is a large government subsidy This subsidy is much higher per car than electrics.

 

gotta feeling some folks are kinda close minded & not reading up. so ok then ... I guess there's really no reason we're not all running on hydrogen then. conspiracy? bowing out

 

Hydrogen cars ?

ROFL
Yet another GW Bush oxymoron.

 

Strangely enough, the only way petroleum 'wins' is with large subsidies, too. The ultimate aim of government - to do what's best for everyone over the long term - has been perverted and subverted to serve special interest groups. I don't expect that to change in my short lifetime, but if humanity is to be successful, things have to change.

 

Certainly not. With no subsidies gasoline and diesel would definitely win out against hydrogen. If externalities were added to the price of gasoline, hybrids and phevs might beat pure ice vehicles. Hydrogen would clearly lose. There is no political will to add these externalities to the price, maybe we can end the oil subsidies though. I support incentives to help develop plug-ins in this early phase, and hope soon they will be competitive without subsidies.

 

Hardly. Historical perspective is important

Hydrogen Fuel Cars 1807 - 1986

This does not mean they are practical. They were pushed by California Air resource board and GM, as well as foreign car companies and governments.

Bush did go along with this part of the fuelishness

It may be Govenor Brown can still come to his senses and kill this stupid hydrogen idea in california. The state could instead encourage hybrids and plug ins instead of a moon shot to the hydrogen highway. Hydrogen is still in the ZEV mandate, and CARB still is slowing adoption of phevs by its policies. Brown is pushing this bad idea.

http://www.mercurynews.com/science/...ng-reach-goals-california-attempts-jump-start

I wonder if those environmentalists understand how this move does nothing positive for the environment.