Volkswagen explains why batteries, not fuel cells, are the right choice for passenger cars

The debate over hydrogen fuel cells refuses to go away. The founders of Tesla considered hydrogen and other energy storage media before deciding that batteries were the best choice for electric powertrains, and have explained their reasoning in great detail several times since. Toyota, on the other hand, continues to insist that fuel cell vehicles (FCVs) will someday overtake battery-electric vehicles (BEVs). Other automakers, including Hyundai and BMW, continue to research both powertrain options.

Now Volkswagen, which at the moment has the most promising electrification strategy of the legacy automakers, has released an article explaining in detail why it has abandoned hydrogen in favor of batteries.

Battery or fuel cell, that is the question includes easy-to-understand charts illustrating how a fuel cell vehicle works, and how the well-to-wheels energy storage cycle of hydrogen compares to that of batteries. It cites several recent studies in support of its conclusion that BEV is the right powertrain choice for passenger vehicles.

VW presents three main arguments against FCVs (there are others): hydrogen is less efficient as an energy storage medium; fueling a vehicle with hydrogen will remain more expensive for the foreseeable future; and hydrogen will not be an ecologically sound alternative until methods for generating it using renewable energy come into widespread use (currently, most hydrogen is made from natural gas).

The efficiencies in comparison.

“Science is largely in agreement on this issue, as several recent studies have shown,” write VW’s authors. “The [German] Federal Ministry for the Environment, for example, assumes that hydrogen and synthetic fuels, so-called e-fuels, will remain more expensive than an electric drive, as more energy is required for their production. The Agora Verkehrswende (traffic transformation) initiative also points out that hydrogen and e-fuels do not offer ecologically sound alternatives without the use of 100 percent renewable energies, and that, given the current and foreseeable electricity mix, the e-car has by far the best energy balance.”

The tragic flaw of hydrogen vis a vis batteries is its far lower efficiency. Citing a study by Horváth & Partners, VW’s paper explains:

With battery-powered e-cars, only eight percent of the energy is lost during transport before the electricity is stored in the vehicle’s batteries. When the electrical energy is converted to drive the electric motor, another 18 percent is lost. Depending on the model, the battery-powered e-car thus achieves an efficiency of between 70 to 80 percent.

In the case of the hydrogen-powered e-car, the losses are much greater: 45 percent of the energy is already lost during the production of hydrogen through electrolysis. Of this remaining 55 percent of the original energy, another 55 percent is lost when converting hydrogen into electricity within the vehicle. This means that the hydrogen-powered e-car only achieves an efficiency of between 25 to 35 percent, depending on the model.

In concrete terms this means that a hydrogen car consumes two to three times more electricity for the same distance than a battery car. But we cannot afford this kind of energy waste. The scarce green electricity must be used as efficiently as possible in the future. Hydrogen would therefore be a serious mistake for passenger cars.

However, as many experts agree, hydrogen does have a promising future as an energy storage medium for industrial processes and for certain heavy-duty vehicles. “We believe that there is great potential if green hydrogen is pushed into applications where it can really establish itself in the long term,” write Horváth & Partners. “Above all in industry, but also in heavy-duty transport, aviation and shipping.”

The Fraunhofer Institute agrees that hydrogen has a role to play: “not so much in the passenger car sector, but rather in long-distance and heavy-duty traffic, as well as in rail, air and sea transport. These segments will only be converted in later phases of the energy turnaround, i.e. beyond the year 2030, and closely linked to the expansion of renewable energies.”

The conclusion of Volkswagen’s paper: “From every angle of the environmental balance sheet, everything speaks for the battery-powered e-car. The technology is mature and ready for the mass market. The number of models is growing steadily. And with the battery-powered e-car, driving remains affordable. Current e-models are already at the price level of comparable combustion engine models. In contrast, the hydrogen car will always remain more expensive than the battery car, due to the complex technology and high fuel costs.”

“No sustainable economy can afford to use twice the amount of renewable energy to drive with fuel cell passenger cars rather than battery-powered vehicles,” says study leader Dietmar Voggenreiter. Fortunately, the market has already spoken. According to VW, there are already more than 130,000 BEVs on the road In Germany compared to a little over 500 fuel cell vehicles.

Source: Volkswagen via InsideEVs

  • Denise Kolb

    Another important factor not brought up in the paper is that if a battery EV owner has solar panels on their roof, as we do, the power generated can go directly into the car battery. Not so with fuel cell cars. We like the idea, and the efficiency, of eliminating “big brother” from our energy needs, and so a battery EV works for us.

    • John Lin

      That is a false assumption.
      FCEV can also utilize a solar panel if included one. However one must realize that solar panels on cars provide very little charging due to small area, thus they are typically used to power accessories such as head unit in cars and such

      • Denise Kolb

        Sorry for the confusion – I was talking about an array on the roof of our home that puts out several kilowatts. With my energy meter, I have watched as the car charged with power from the array and there was still excess power for the house to use. It’s a win-win for us.

  • Jim Young

    My understanding is that they do have Hydrogen Production Appliances, but they are still expensive and take 4 times, or so, the energy to produce it cleanly.

    I do believe there is a place for the technology in the future, especially for generating it locally from surplus solar or wind, etc.

    It seemed to me the unitary system to be tested on the Helios 3 was half the weight of the best batteries at the time (double the energy density), but more importantly, may not become financially viable until the raw materials limits come into play.

  • mrrumbles

    @denise_kolb:disqus A few points of disagreements with VW’s analysis:
    1. They have low-balled the tank-to-wheel (TTW) efficiency of an FCV. Instead of 45%, it’s likely higher–above 50%. EVs are more efficient, but true numbers should be used for both powertrain types.

    2. The faster recharging times that are coming for EVs is mentioned as if this will solve the issue entirely. That is not the case. Taking powertrain efficiencies into account, EVs charging at 350 kW (much, much higher than EVs can today) are actually charging at 291 kW. An FCV is refueling at an energy equivalent rate of 1.3-2.1 MW. So refueling is an order of magnitude faster. This has serious consequences for those who often travel long distances.
    3. @Denise Kolb: Completely agreed that this is an advantage for EVs. I don’t have solar panels (yet!) to charge my EV, but it’s an attractive feature. However, the flip side of this is that there are many without access to home (or work) charging, and so owning an EV will always require commercial EVSE charging. This is much more expensive and eliminates much, if not all, of the operating advantage of EVs. Moreover, because recharging an EV will always take so much longer (see #2, and that’s for XFC charging…most EV charging will be more than two orders of magnitude slower), not being able to charge at home makes owning an EV in this case much less convenient.

    • Matjaž Ciglar

      Read the article again… and then read your Nr.: 1 again
      1. VW assumes that loses are 45% not efficency
      2. when you are travelling long distances you need more time off than car charging. Otherwise you are hazardous driver if you are driving without rest. Car is usually recharged at home, so no need for 90% of stops or more. You cant have “pump” at the home.
      3. If some third party chargers are now more expensive is due to low volumes, with competition prices will fall.

      • mrrumbles

        1. Actually, I think that you are the one that should re-read the article. The 45% initial losses are for well-to-tank (WTT) (i.e., getting the H2 inside the FCV). VW then assumed that of the remaining energy, 55% are lost in the powertrain getting power to the wheels for tank-to-wheel (TTW), so only 45% efficiency, as I described.

        2. Your first statement is without evidence. At which point does a driver become hazardous? As for the second, it’s true that on average, EV owners are recharging 90% or more at home. But see #3. Also, I noted that this would be a problem for someone who drives long distances frequently, which you seem to have ignored for some reason.
        3. Charging away from home will always be more expensive, since at home you are paying just for the electricity and you can even charge at opportune times when the electricity price is lower. This is not true for commercial EVSE. So no, you can’t dismiss this as an issue for those who cannot charge at home.

  • bob

    This has been my issue all along. Hydrogen has to be produced and the use/loss of energy to make it is an issue. Plus the equipment to make it is not cheap.
    Dennis Kolb also misses a few points to consider. As range improves travel distance increases and therefore less charges should be the norm. This should balance out as more chargers come online to handle more cars. I started with a Leaf with a range of 100 kms. Now I have a Tesla with a range of 500 kms. I have driven coast to coast. In time I will still be able to do so but with better batteries my stops will be less often and more likely shorter. Whenever I am asked to give a talk about these two energy sources I mention a few major points. 1) I most likely will never have a hydrogen charger at home. 2) the cost of hydrogen filling stations will cost more that EV stations to build. 3. Unless they build 20 hydrogen stations together, you may need to wait longer to get a fill than if there were a number of EV charge stations. 4. Lastly, hydrogen will , as with gas, be controlled by big oil or some other major company. An L2 charger can be in your garage or at a store, etc. And while we may pay for charging, many business owners will have free charging as a perk for shopping at their stores. Just something to consider.

    • John Lin

      In response to your points:
      1) Hydrogen may not be available to households in the near future, yes. But homes and commercial buildings are already being built utilizing fuel cells as backup power, additionally hydrogen can be transported in the same pipeline as natural gas, even same exact pipe as they are easily separated. So to say this won’t happen is a bit far fetched.
      2)cost of hydrogen is currently roughly the same as gasoline to refuel, but keep in mind this is with very low demands, thus supply is low and cost is high. If and when there is more demand for it, cost will naturally go down as supply increases.
      3)refueling hydrogen takes roughly the same time as gasoline, around 3-5minutes.
      4)agree for the most part, but refer to my first point regarding in-home hydrogen