Let’s talk about the Hydrogen drive
Volkswagen recently released a quite interesting
comparison of the battery-electric (BEV) and hydrogen fuel cell (FCV) path to
zero-emission mobility. The conclusion is that the only way to go for passenger
cars is battery-electric cars.
But let's see the
details and explain the differences between BEVs and FCVs.A
BEV is equipped with a relatively large rechargeable battery, which supplies
electricity to the inverter and then electric motor. In the case of FCVs, the
battery is very small because it works only as a buffer between the power
electronics/motor and the hydrogen fuel cell. The fuel cell stack provides
electricity, consuming hydrogen, stored in tanks at high pressure.
When comparing the BEVs with FCVs, Volkswagen
refers to studies, which say that hydrogen fuels (as well as synthetic fuels)
will remain more expensive than driving all-electric (BEV). The reason for that
is simple: more energy is required to produce them (compared to electricity and
charging).
Moreover, the greener
the electricity is the higher the advantage for BEVs. FCVs turn out to be "very
inefficient – both in terms of efficiency and operating costs".
The only light in the tunnel for FCVs is maybe
long-distance heavy-duty vehicles, as well as in rail, air and sea transport -
but it's not yet proven commercially. Battery electric trucks are also coming.
"Science is largely in agreement on this
issue, as several recent studies have shown. The 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. In the view of the Fraunhofer Institute, synthetic fuels
and drive technologies such as hydrogen in combination with the fuel cell will
indeed play a role – but 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."
"In fact, hydrogen-based fuel cell
technology has one crucial disadvantage: it is very inefficient – both in terms
of efficiency and operating costs. This is also confirmed in detail by a Horváth
& Partners study, comparing both types of drive for e-cars from the
customer’s point of view."
Dr. Frank Welsch, Member of the Board of
Management of the Volkswagen Passenger Cars brand with responsibility for
Technical Development said:
„If we want to take the mobility turnaround
and the environmental goals seriously, we must focus on the battery-electric
drive. Everything else is a waste of the limited regenerative energy."
Efficiency comparison
According to studies,
all-electric cars can achieve an outstanding overall Well-to-Wheel efficiency
of 70-90%, depending on a particular example.
"In its study “Automotive Industry 2035 –
Forecasts for the Future”, the management consultancy recently had a detailed
investigation carried out into whether battery- or hydrogen-powered e-cars will
become established in the future. The study was prepared over six months,
accompanied by 80 people/interview partners and financed by the management
consultancy itself. “The main reason for our study was that Horváth & Partners
serves many clients in the automotive supply industry. Of course, these clients
want to know what to expect in the next 10-to-15 years,” says study director
Dietmar Voggenreiter, explaining the report.
So which energy storage system has the best efficiency
and is the most cost-effective for powering electric cars? 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."
The hydrogen fuel cell
requires 2-3 times more energy to drive the same distance, as the overall
Well-to-Wheel efficiency is from 25-35%.
"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. For the sake of completeness: the efficiency is even
worse with alternative fuels. The overall efficiency here is only 10 to 20
percent.
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. “In addition to the
very real potential of green hydrogen, there is a dangerous hype going on right
now," warn experts from the Boston Consulting Group (BCG) in a study
quoted by the Handelsblatt. The Horváth&/Partners study comes to the same
conclusions.
However, hydrogen offers very promising
prospects – although not for cars. The authors of the study conclude that
investments should rather focus on other areas where they make ecological and
economic sense. “We believe that there is great potential if green hydrogen is
pushed into applications where it can really establish itself in the long term.
Above all in industry, but also in heavy-duty transport, aviation and
shipping,” says Frank Klose, co-author of the study."
The conclusion
As we many times pointed out over the years,
hydrogen fuel cell cars have three serious drawbacks:
·
high initial cost of the vehicles (higher than battery-electric)
·
high fuel cost (higher operational cost than battery-electric)
·
lack of refueling infrastructure (BEVs at least have some in
form of home charging, which covers most of the daily charging needs)
The FCV's advantage of range is shrinking as
batteries are getting more energy-dense. Moreover, if you don't have a
refueling infrastructure nearby, you have to go to a certain hydrogen station -
not necessarily along the route, which cost time and... range. So basically
there is no range advantage in practical use.
"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. Drivers already pay around nine to
twelve euros per 100 kilometers for a hydrogen car, while battery cars cost
only two to seven euros per 100 kilometers (depending on electricity
prices in individual countries). And the topic of long-distance travel? That
will soon no longer play a role. With the new generation of e-cars, ranges will
increase to 400-to-600 kilometers, while charging will become increasingly
faster."
