By Paul Homewood
Harrabin never gives up!
In his speech on the planned economic recovery, the prime minister said hydrogen technology is an area where the UK leads the world. He hopes it’ll create clean jobs in the future. But is the hydrogen revolution hope or hype?
The digger with the long-toothed bucket bites into a pile of stones, tilts up and flexes its sturdy mechanical arm.
It swivels, extends the arm and dumps its load on the harsh ground of a Staffordshire quarry.
It’s a beast of a machine and from the front it looks like a normal excavator.
But from the back you can see its tank full of dirty diesel has been replaced with a hydrogen fuel cell.
The excavator is the latest in a generation of vehicles powered by the lightest element on Earth.
The compendium of vehicles powered by hydrogen now stretches from diggers to micro-taxis, trucks, boats, vans, single-deck and now double-decker buses – and even small planes.
It works by reacting hydrogen with oxygen in a fuel cell to generate electricity. The only direct emission is water.
He goes onto to plug trials of hydrogen buses and trains, but for once gives the other side of the story:
“So it looks as though hydrogen has finally made it. But not so fast… because it’s by no means trouble-free.
Currently almost all the hydrogen sold in the UK is produced by splitting it from natural gas. But that’s costly and emits lots of planet-heating carbon dioxide.
The problem can be tackled by capturing the CO2 at a hydrogen production hub, then burying it with carbon capture and storage. But that will drive the cost up further.
The alternative is inherently clean – but very expensive. It entails using surplus renewable electricity, like when the wind blows at night, to split hydrogen from water using a fuel cell.
The process is wasteful because it involves turning electricity into a gas, then back into electricity – a two-step shuffle dismissed by Tesla car chief Elon Musk as “staggeringly dumb”. “Fool cells”, he calls them.
But hydrogen-lovers believe the future electricity grid will produce so much cheap off-peak power that we’ll need to find other uses for it. And they hope to see the cost of fuel cells plummet following the example of offshore wind.
And, of course, that is the very real problem. Nobody has ever doubted that you can burn hydrogen, or use it in fuel cells. It is the hugely inefficient and costly production methods, along with the problem of distribution and storage, which explains why it has never taken off.
Harrabin hopes that we can take advantage of cheap off-peak power. But this shows up his lack of economic knowledge. He is plainly talking about wind and solar power here, as the electricity obviously needs to be zero carbon. But if power is given away at low prices when demand is slack or output high, it simply makes the unit cost higher the rest of the time.
The economics of wind and solar power depend on all of the output being sold. Giving large amounts of it away would alter the business case, and electricity users would end up paying the bill. This would put paid to claims, propagated by Harrabin, that renewable power is now cheaper than conventional.
And the economic downside does not end there. The unpredictable intermittency of wind and solar power would necessitate a huge overcapacity of electrolyser units, able to take all of the surplus power available at any particular time. These electrolysers would then not only run at well below capacity, but would also have to ramp their outputs up and down on an hour by hour and day by day basis.
I know of no production processes that can work efficiently on that basis.
On top of that would be the seasonal surpluses. Logically, most of the surplus power would arise in summer, but most of the demand for hydrogen would be in winter (if it was used for heating). Whilst there is talk of using salt caverns for storage, even the Committee on Climate Change realises that there is no practical solution at the moment, which is why they are still recommending steam reforming as the main solution.