Rosemary Barnes: What is the go with hydrogen these days?!
Everyone is talking about it all of a sudden. It is literally the
most abundant element in the universe and also plentiful on
earth making up two thirds of the atoms in water and present
in vast volumes of organic compounds.
Hydrogen was first produced artificially in 1671. And
discovered as an element in 1766. It has been quietly going
about its business for hundreds of years before suddenly, a
couple of years ago, people started to pay attention. It's
fair to say that right now hydrogen is having a bit of a
moment.
Now, I love a new technology, pretty much any new technology
gets me excited, but I will admit that I am a little bit
confused and conflicted about hydrogen.
The current hydrogen hype is mostly about green hydrogen,
that's hydrogen produced from green electricity in a process
called electrolysis. It's interesting now because it's a
way that we can essentially store surplus electricity. And
as we incorporate more and more variable renewable energy
sources to our grid, it's expected that we will have a lot
of time where we have much more electricity than we can use.
Currently, we can store this via batteries or pumped hydro. And
green hydrogen is is another option.
Now making hydrogen from electricity is not an
innovation. This process has been around for over 200 years.
But hydrogen produced in this way is rare and makes up only a
tiny fraction of the current global hydrogen production. The
vast majority of today's hydrogen comes from fossil fuel
sources. If hydrogen is made from natural gas, it's either
grey if CO2 emissions aren't captured and stored, or it's
called blue if they are.
Today, the primary uses of hydrogen are in industrial
processes like oil refining, and ammonia and steel production.
But the current hype about hydrogen, is not to replace
dirty hydrogen for cleaning these existing applications.
Instead, the plan is to expand to a range of new applications
like passenger cars and electricity generation amongst a
lot of others.
Now, on the one hand, I think it is really cool to see a lot of
governments rallying behind a new technology development that
could potentially speed the green energy transition. But on
the other hand, I'm sceptical about many of the proposed
applications.
I don't doubt that there are several things that you can do
with green hydrogen that will really make a good contribution
to the green energy transition. Like it has the potential to
help reduce emissions in several hard to abate sectors like steel
and cement manufacturing, shipping and aviation. But these
aren't really the applications that I hear politicians talk
about mostly, and that's the source of my confusion.
Probably the most hyped aspect of the imagined future hydrogen
economy is smoothing a variable generation from renewable energy
sources such as wind and solar. The argument goes that as we add
more and more variable electricity generation there
will be a lot of times when there is way more green energy
supply, then there is demand. At such times of oversupply, the
price of electricity will be zero or even negative and green
hydrogen manufacturing facilities can use this free
electricity to turn water into hydrogen to be stored for future
use.
The second application that governments are really pushing
for hydrogen is passenger cars, at least 16 countries have
incentives or targets for this application, making it the one
with the most government policy support out of all of the
different applications for hydrogen.
This all sounds great! Renewable electricity generation is
variable. So in the future, we'll have surplus energy we can
use for free to make hydrogen and hydrogen passenger cars will
be just like the internal combustion engine cars that
we're all used to, except for they won't harm the environment,
perfect! But when you look deeper into these two
applications, I can see four red flags that might derail
government plans for a full hydrogen economy.
The first problem is that the business case for green hydrogen
seems to depend on very low or negative electricity prices
occurring a lot. But wind farm developers, for example, would
not build wind farms if they're expecting a lot of electricity
to be generated at times of low or negative prices, the same is
going to be true for solar or any other form of electricity
generation. The business cases wouldn't add up. Banks wouldn't
lend to them under these conditions. I just really can't
believe that anyone's going to be investing in wind farms or
solar or any type of electricity generation that will experience
persistently low or negative energy prices. The economics
won't make sense in this situation unless governments
step in with with really big subsidies.
The second problem that I can see is that for the green
hydrogen storage or passenger car business case to work, the
cost of green hydrogen needs to come way down. As well as
needing very cheap electricity, the manufacturing process also
needs to become cheaper. Now, one of the main drivers of cost
savings in an expensive manufacturing facility is to
make sure that it's fully used. That means getting close to 24/7
production and not just waiting around for periods with low
energy prices before you turn your really expensive equipment
on. But in recent years, there have been negative electricity
prices less than 2% of the time in Germany, which is a country
with one of the highest proportions all variable
renewable generation in that electricity grid. Electrolyzers
are expensive, you can't make cheap hydrogen if you're only
using your expensive equipment 2% of the time.
The third problem is efficiency, it's very efficient to put
electricity straight to the grid without storage. Where storage
of any kind is required, energy is transformed from one form to
another. So there are always going to be some losses.
Batteries are pretty efficient. So you get back around maybe 95%
of the electricity that's been stored in the batteries before
going back to the grid. And if you use it to power a battery
electric car, it's about 80% efficient. For hydrogen storage,
the efficiency is much lower than losses from the
electrolysis process where electricity is used to turn
water into hydrogen and oxygen. Then there are losses from
storage and transportation. And finally, there are losses when
you use the hydrogen to produce electricity again, whether to
the grid or in a fuel cell electric vehicle. After all
this, the round trip efficiency is around maybe 35%. So you need
two to three times as much electricity production for the
same outcome. If you store the energy as hydrogen instead of
batteries or putting it directly into the grid, which is
obviously the best of all. Given that few countries have
anything close to a zero emissions grid, that means that
for now at least, you are nearly tripling the emissions from
electricity production every time you use hydrogen for
something that could have been electrified. Now, of course,
these efficiencies should improve as hydrogen technology
matures, but never to zero. Based on today's technology
maturities, there is a big gap to be overcome by improved
hydrogen technology. And remember that the alternative
technologies are improving too.
Now that brings me to the fourth problem I see. Which is that the
case for developing hydrogen storage seems to ignore that
other technologies have a head start and are improving rapidly.
A lot of the discussion around hydrogen compares the current
state of storage and grid technology with hydrogen
technology expected after 20 years development. Old
technologies are going to continue to develop in the
meantime, they're not standing around still, just waiting for
hydrogen to catch up. For hydrogen to become a mainstream
storage option, it needs to progress faster than the alternatives.
In many ways, hydrogen behaves like a lot like a fossil fuel,
it can be transported in gas pipelines and burned in gas
turbines with just probably some small modifications. Maybe you
can use it for heating and you can even convert an internal
combustion car engine to run on hydrogen if you really wanted
to. These similarities make it easy for fossil fuel companies
to support it and for governments of resource based
economies to feel comfortable with it. Now, as I mentioned at
the start today, most hydrogen is not green, but it's made from
natural gas or coal. It's gray or brown hydrogen. I think
there's a risk that if we build the hydrogen infrastructure
first without cleaning up our electricity generation, I wonder
if it turns out that we don't achieve our green hydrogen goals
we might make up the shortfall with gray hydrogen instead.
Until we reach a 100% clean electricity grid they will be
emissions associated with hydrogen. Unavoidable
inefficiencies in hydrogen production and storage mean that
hydrogen used for anything that could have been directly
electrified will end up increasing emissions. When
electricity grids become 100%, renewable, and if the imagined
surplus of renewable energy eventually it's only then we'll
hide it in use for storage and electricity actually be green.
So at the start, I did say that I am excited about hydrogen
technology development. And now I've pretty much just gone on
and on about the negatives. I do think that there are plenty of
opportunities for hydrogen to contribute to a future green
economy. And there are applications where hydrogen
technology is particularly promising.
For the case of using hydrogen as storage by electricity
generation, there are some specific situations where the
red flags that I outlined earlier are not relevant, like
for example, locations that have excellent renewable energy
potential but are too far away to connect to existing grids
cheaply. Another example would be that you could use wind
turbines to produce hydrogen rather than electricity to the
grid directly. So this would this would mean you could avoid
some turbine inefficiencies and in the case of offshore wind,
you would avoid the considerable costs of undersea cables.
Another potential application is for long term energy storage.
Many locations have very different energy demands for
winter than in summer. And if we can solve the challenges
associated with hydrogen storage, then it could provide a
better long term storage option than batteries could.
There are also several hard to electrify sectors where hydrogen
may present an opportunity for a more straightforward solution.
Some examples that sound exciting to me are industrial
processes like steel and cement manufacture. And these two
together make up actually a really large proportion of the
world's carbon dioxide emissions. Maybe also aviation
where the weight penalty for using batteries instead of
aviation fuel is a really big challenge. Very long haul
trucking transport is another area where batteries are not
quite up to the challenge yet. All of these applications also
have the possibility of electrification. But in each
case, the technology is years away from maturity, and so
hydrogen has a chance to win the rest of technology dominance in
these applications.
So I am cautiously optimistic about hydrogen's potential to
help with a green energy transition. But hydrogen is
definitely no silver bullet, and I'm concerned that many people
are talking about it as if it is the single answer to all of our
climate problems, it will be very easy to get perverse
outcomes if we don't carefully target hydrogen to the right
applications where it has the most potential to reduce
emissions. There are plenty of opportunities like this, but the
widespread use of hydrogen to store and then generate
electricity to the grid... In my opinion, this is amongst the
least likely.
I am also unconvinced that passenger cars running of
hydrogen makes much sense. Battery electric cars require
far less electricity generation and the perceived benefits of
hydrogen passenger cars compared to battery electric cars like
longer range, faster refueling, these differences are
diminishing rapidly as battery technology improves. I think
that by the time hydrogen cars can get there battery cars will
be there already.
The real potential for hydrogen is going to lie in the niche
applications where the conditions are just right for
hydrogen to gain an edge over alternatives. Identifying and
prioritizing these will be important because currently, the
world's production of green hydrogen is very tiny. As green
hydrogen production capacity increases, it shouldn't go to
applications in which electrification is an option.
So this video is just the first in a series that I'm going to be
making on hydrogen technology. In future videos, I'm going to
be visiting hydrogen projects and all sorts of applications
and talking to the experts working on these projects, to
find out where is the best potential for green hydrogen.
This will include looking more into those applications that
have kind of ruled out in this video, like using hydrogen for
electricity storage and generation and for passenger
cars. I'm keeping an open mind. I want to learn more from people
who know these industries better than I do see if I'm missing
something. And I'm totally open to having my mind changed about
these technologies. And in a way, I hope that I'm wrong. A
hydrogen economy has so much exciting potential, I hope it's
going to happen. But for sure, we need to be careful about how
it's done to avoid perverse outcomes, which will be so easy
to achieve if we just rush headfirst into hydrogen
everywhere without thinking about why.
So please subscribe if you're interested to take a deep dive
into hydrogen technology with me. And if you're working on a
hydrogen project that you would like to share, and especially if
you think that I am totally wrong about which applications
have potential and you want an opportunity to tell me why then
please get in touch with a comment on LinkedIn or Facebook.
I'll see you next time.