If we want carbon capture to work, we urgently need to value putting carbon back in the ground – or crazy stuff like this happens…

There’s a lot of excitement, a lot of hype, and a lot of money floating around to do interesting things with renewable power, carbon, and especially hydrogen. And I think it’s sending some project developers a little crazy. Here’s an example:

‘HydrogenInsight’ recently published an interview with Thomas Zirngibl of Koppo Energia Oy, a Finnish company (link below). Thomas seems like a nice enough chap, and admittedly, he recognises that what they’re doing is a bit crazy – the headline is, ‘This is why we’re producing e-methane from green hydrogen, even though it’s so inefficient’. Having read what he’s planning, I think someone needs to explain to Thomas the difference between ‘inefficient’ and ‘worse than pointless’. See what you think.

Koppo Energia will build a large green hydrogen production facility on Finland’s west coast, with a 200MW electrolyser powered by 500MW of offshore wind and 100MW of solar. But, they need a market for all that hydrogen, which means moving it. In future, conversion to ammonia would make sense, but there are no buyers yet. So, they’re going to combine it with captured CO2 trucked in from another plant, make e-methane, then liquefy that methane and truck it down to Germany to fuel LNG-powered trucks.

Just think about that for a moment… The starting point is that a plant has captured the CO2 it emits. Energy is then used to truck those carbon atoms to a second plant. More energy is used to purify water, more to electrolyse that water to hydrogen, more still to combine that hydrogen with the carbon, even more to liquefy the resulting methane, and a final amount to truck that methane to Germany, where it is burned in the engine of a truck – turning it back into CO2 which is released to the atmosphere.

The outcome of this whole process in carbon terms is exactly the same as if the CO2 captured at the original plant in Finland was simply injected into an oil well or sequestered in some other way. That sequestration would achieve exactly the same CO2 reduction as using those carbon atoms to replace German truck fuel, and I would be willing to bet at far less cost?

Plus, you could do something else with all that wind and solar power, and the money you invested in the electrolyser. If you want a load of kit, you could invest in another Direct Air Capture plant like the one in Iceland, and use all that power to lock up even more CO2 from the atmosphere directly – OK it’s not very efficient either, but again, probably makes more sense than what Thomas is planning, and would certainly mitigate more CO2 overall.

 On reading about this plan, the question has to be, how did we arrive at a point where anyone would think this is a plan worth spending money on? I assume some pretty detailed financial modelling has been done, and the investors aren’t stupid, so this scheme suggests a couple of things are going on.

Firstly, it seems likely that the current systems of grants and subsidies in Finland and Germany are overly eager to promote hydrogen and/or recycled carbon fuels, and are being ‘gamed’. That sort of market distortion is not uncommon where multiple stakeholders are finding different mechanisms to promote new technologies.

Second, and more importantly to my mind, the Finnish plant at the start of the process is apparently unable to get a decent price to bury its CO2 emissions. With all the talk of carbon sequestration in the context of BECCS and ‘Blue Hydrogen’, it does not bode well to see an example of a plant that has gone to the trouble of capturing its CO2, but isn’t taking the simplest route to put those carbon atoms back in the ground.

BECCS – BioEnergy with Carbon Capture and Storage

https://www.hydrogeninsight.com/transport/interview-this-is-why-were-producing-e-methane-from-green-hydrogen-even-though-its-so-inefficient/2-1-1495170

What are the implications if ‘white hydrogen’ isn’t a white elephant?

So you’ve probably heard of grey, blue and green hydrogen – I won’t explain here, if you haven’t then google it and then come back. But as of the last few days, you may also have heard of ‘white’ hydrogen (also sometimes called ‘gold’ hydrogen). I first came across the idea earlier this year, and I’ve been meaning to write about it, but this week it hit the mainstream with a piece in the Telegraph.

White hydrogen is hydrogen that forms naturally in the rocks under our feet, like oil (although by a different process, and in different rocks). And some reliable sources (like the US Geological Survey) have estimated that there may be a lot more of it than anyone had previously guessed – enough to entirely replace the fossil fuel industry with hydrogen that we can extract at about the same cost as those same fossil fuels.

If you’re like me, and most other commentators, your immediate reaction is, that sounds too good to be true, because surely we couldn’t have missed something that big? Right? Well, I’ve linked to some other sources below, but to summarise:

  • People have noticed seepages of hydrogen from rocks all over the world for a long time. The same was true of oil for hundreds of years before anyone thought of developing it.
  • Hydrogen forms in completely different rocks to oil, so we haven’t looked in the right places at all.
  • People prospecting for oil (and other things) just haven’t been testing for hydrogen.

So, it is possible that vast reservoirs of naturally occurring hydrogen exist under our feet and haven’t been found. Surprisingly little of the earth has been comprehensively geologically mapped.

One key thing about white hydrogen is that it is continuously being formed, mainly by water reacting with certain types of rock. That means that if/when a reservoir is tapped, it may well keep producing forever, as unlike oil the hydrogen is continuously replenished. In fact there is the tantalising prospect of a win-win-win – pumping water and carbon dioxide down a hydrogen well, where the CO2 reacts to form rock, some of the water creates fresh hydrogen, and the rest of the water is heated. The heated water and hydrogen then circulate back up, providing geothermal and hydrogen energy.

Of course it’s impossible to know at this point how much H2 might be economically recoverable, and how long this industry might take to develop. But there is the chance it could happen quite quickly – after all, we have a load of highly capitalised global companies specialised in this type of thing, that we’re currently telling to abandon their primary product.

What would be the implications is we could suddenly produce as much hydrogen as we could use, at a cost per unit of energy comparable to oil? A major worry is that even considering that question might lead to a stalling of current efforts to decarbonise using existing technology. However, I think that’s unlikely – even if we find huge amounts of white hydrogen, it will still mainly dovetail with wider efforts at electrification, we’ll just have more fuel cells and fewer batteries.

The fuel cell industry will be a massive winner, as the economics of fuel cells vs bigger batteries will win out for more vehicles. Efforts to decarbonise current industry with hydrogen will get a huge boost – primarily fertiliser, but also steel and chemicals. And it will make decarbonising shipping with ammonia as a fuel far more attractive. Electrolysis may be a big loser, but then again maybe not – hydrogen will still be hard to transport, and if the use of hydrogen becomes far more widespread, then there may well be interest in producing it by electrolysis in locations further from hydrogen wells.

Then of course we have to consider the possibility of leaks, and whether hydrogen is itself a pollutant? Hydrogen is not itself a greenhouse gas, and it doesn’t last long in the atmosphere, but it does increase climate heating by prolonging the life of methane in the atmosphere, and its effects on ozone. However, some useful work has been done on this by the UK government, which concluded that since some hydrogen is created by the burning of fossil fuels anyway, the amount likely to leak in a hydrogen economy would be less than the reduction in hydrogen from the fossil fuels we would have burned instead. Still, leaks would need to be closely regulated from day one if drilling for hydrogen takes off.

Overall, this may sound a little far fetched, but I think it’s something that everyone in the transport and energy space needs to keep a close eye on. It’s just possible that ten years from now the energy economy could look very different from any of the current predictions.

https://www.science.org/content/article/hidden-hydrogen-earth-may-hold-vast-stores-renewable-carbon-free-fuel

https://www.usgs.gov/news/technical-announcement/less-one-percent-united-states-covered-aeromagnetic-data-meet-modern

https://www.businesstimes.com.sg/opinion-features/columns/could-white-hydrogen-change-everything-shipping-and-everybody-else

The ‘where’ approach to sourcing green hydrogen…

So, can we import lots of green hydrogen from places with abundant renewable electricity potential, but no market within cable-laying distance – what I call the ‘where’ solution? The short answer is much the same as for making hydrogen from curtailed renewables here in the UK, i.e. yes we can but it’s likely to be quite expensive, so its niche will be restricted to those areas with very little other option to decarbonise.

There are various ways that hydrogen could be transported, the main ones being:

  • Pipeline
  • Compression
  • Liquefaction
  • Convert to ammonia or methanol
  • Lock into metal hydrides or liquid organics

Since hydrogen is literally the least dense form of chemical energy in the universe, transporting it is inevitably going to be difficult. The following article does a good job of explaining those difficulties in detail – https://www.linkedin.com/pulse/myth-hydrogen-export-spitfire-research-inc/

I’m not technically qualified to attest to its accuracy, but even if the specifics can be debated, the broad picture is clear – moving hydrogen over long distances entails additional energy losses and significant capital costs. Just to recap the key points in brief:

Pipelines – hydrogen is a very small molecule that will leak through any sort of plastic pipes, and makes most types of metal pipe brittle and thus more likely to crack. Its low energy density means using a lot more energy in pumping a given amount of energy through a pipeline compared to natural gas.

Compression – very high pressures needed, lots of energy used in compression, and hoop stress limits the size of individual cylinders. Simply not practical for large quantities.

Liquefaction – hydrogen liquefies at -249degC (only 24 degrees above absolute zero), and has a reverse Joules Thompson effect, so that it warms when it expands at temperatures above -200degC. It therefore has to be pre-cooled with liquid nitrogen before final cooling via expansion. The whole process is very energy intensive, and boil-off rates are high.

Convert to ammonia – this releases heat at the point of production (which will probably be wasted as that’s where you have cheap energy) and requires high grade heat to convert the ammonia back to hydrogen at the destination. Ammonia is also poisonous in general, and poisonous to the catalysts in hydrogen fuel cells in particular.

Convert to methanol – as with ammonia, methanol is a useful product, or a fuel, itself, and as a liquid at room temperature is relatively easy to store and transport. The major problem is that it requires a supply of CO2 (and that CO2 will be released when the methanol is burned or turned back into hydrogen). If one has a source of non-fossil CO2 available, either from an AD plant, direct air capture or other, the question is whether it would be better to just bury it rather than make and transport the ethanol?

Lock into metal hydrides or liquid organics – this approach may well have a niche, but in both cases (as with ammonia) heat is needed at the destination to release the hydrogen, and the weight of the carrier has to be transported in both directions, so again round-trip efficiency is low.

So, should we conclude that this is just a non-starter? Well, apparently not. At the ITT Hub show last week I visited the Air Products stand, where they were talking up their plans to make green hydrogen, and convert it to ammonia, in Saudi Arabia, then ship it to a terminal in the UK to turn back into hydrogen. Saudi Arabia may have the world’s largest oil reserves, but it also has huge potential for wind and solar power, and a lot of ready capital to invest. I for one will be watching the development of this project closely to see whether it’s just Saudi greenwashing or whether the economics really stack up.

It’s also worth noting that the world’s second largest shipping line, Maersk, has bet on methanol as its route to decarbonising its ships. They will burn the methanol directly though, rather than converting it back into hydrogen. (I’ll write another post in a few weeks about this.)

Ultimately, I would broadly agree with the conclusions of the article I quoted:

  • Firstly, before we start finding other uses for green hydrogen, we need to make sure we replace all the grey hydrogen we use right now.
  • Second, rather than trying to move hydrogen long distances, we should move some of our industries to the hydrogen supply. An obvious example is to use hydrogen in Western Australia to process Australia’s iron ore and make low carbon steel – then export the metal rather than the hydrogen. All our fertiliser should be made in similar places.

How are hydrogen producers going to get their hands on lots of cheap electricity?

First of all, let me make clear that I’m not ‘anti’ hydrogen – I absolutely think we’re going to need it for some applications. For a start, we’ll have to replace all the ‘grey’ hydrogen we currently use to make fertilisers, and we’ll probably need a lot of hydrogen for steel-making. In applications like that, where there is not really any other zero carbon choice, the question is not whether to use non-grey hydrogen, but how best to do it.

So my question about hydrogen is really about using it where there are competing options – such as in vehicles. Where does the line get drawn between turning electricity into hydrogen and then back into electricity, vs just using the electricity? Physics says that the hydrogen option is always going to need a minimum of twice as much energy compared to using the electrons directly, so for hydrogen to compete, it has to use electricity that is half the usual price, or less.

As far as I can see, there are two possible options for finding cheap renewable electricity to make hydrogen – either ‘when’ or ‘where’. The ‘when’ option is to use curtailed renewables – wind power generated in the middle of the night for example. And the ‘where’ option is to hook up an electrolyser to a wind turbine out at sea or a solar farm in the Australian outback (rather than lay a cable).

Let’s look at the when option first (I’ll tackle ‘where’ in the next post). At the moment, in the UK, if the wind is blowing in the middle of the night, some wind farms get paid to switch off rather than damage the grid, so the electricity price is effectively negative. I can see why people get excited about hydrogen when looking at this. However, I had a client who asked me to assess the feasibility of producing hydrogen from curtailed power, and for now the numbers don’t stack up. The problem is that electrolysers are a big up front cost, so an operator needs to run them continuously in order to generate a return on investment – only running them when there’s excess electricity on the grid is not good enough for investors.

Even if the price of electrolysers falls significantly, my guess is there won’t be enough curtailed power to supply them, for two reasons. One, we are rapidly moving towards a smart grid in which consumers and energy companies collaborate to match demand to supply. And two, we are seeing exponential growth in electric vehicles, which will be left on overnight to be charged at the discretion of the smart grid whenever power is cheapest. Effectively, all those EV batteries will be soaking up the cheap electricity leaving none to make hydrogen.

I would really welcome comments on the above from anyone who has more detailed modelling of the UK electricity grid. My thoughts are purely qualitative, so maybe the scale of renewables we need to meet peak demand is such that we’ll have a huge amount of curtailed power even with EVs and a smart grid. But my suspicion is that the market will match the two, and not leave much for hydrogen production. So what about the where option? That’s for my next post…