Comment by londons_explore | Hacker News Reader

Comment by londons_explore | Hacker News Reader

londons_explore

The biggest roadblock is that today there is no incentive to go green.

Consumers might like to buy their metal drinking straws knowing they were made with green steel.

But the vast majority of steel is used for unseen things... Like building the piling machine that built the flood defences for your city. There is no consumer pressure to go green there. Just commercial pressure to be cheap.

Companies are investigating so they are ready incase such an incentive appears. But I see nothing on the horizon.

Note that this is pretty much out of the hands of government too - if any government mandated that all steel produced in the country was green, then all steel would just be imported and local industry would die. If the government put an import tariff on non-green steel, then makers of steel products like cars would become uncompetitive and close down. If the government gave those steel users a subsidy, it would be against WTO anti-dumping rules.

There is no good solution.

The biggest roadblock today is that there is not enough green hydrogen yet. (Or even of grey hydrogen, really.) And not enough renewable power to make it from. So, the places for investment are renewable energy projects and factories to make electrolysers. It takes a long time to tool up factories, before you even start down the learning curve.

Somebody has worked out a way to get electrolysers well over 90% energy-efficient. We will need a hell of a lot of those.

The incentive will be that hydrogen will have become vastly cheaper than coal, and nobody still using coal will be able to compete. Until then, using coal is no worse than using grey hydrogen. But those already using grey hydrogen will be in a better position to switch to the cheaper alternative. And grey hydrogen could anyway become cheaper to use than coal.

It will be hard to find investment for tooling up to make gargantuan amounts of grey hydrogen, because the market will vanish in a few years and the equipment will be worthless.

Aviation, with LH2 vs kerosene fuel, will have a similar dynamic. That case is particularly slanted, because a given amount of hydrogen enthalpy is much lighter than of kerosene, and the difference is saleable cargo capacity. So, if liquified grey hydrogen is not very much more expensive than kerosene, it might be a win already. It is not clear whether airframes can be retrofitted; with long under-wing nacelle tanks, it might be possible.

> The biggest roadblock today is that there is not enough green hydrogen yet

Not enough of something will always be fixed relatively quickly by markets. If you went out and purchased all the hydrogen you could buy from your local bottled gas supplier, then tomorrow they'd be out of stock. If you did it every month, they'd soon be producing more gas each month.

Right now, there is plenty of green and grey hydrogen available to buy, but nobody wants to pay the (high) price of it.

"Always"? Depends on what it takes to increase supply, and how long it will be wanted. As I noted, the writing is on the wall for grey hydrogen, so building out grey production capacity would seem a poor place to put capital. So the price for grey probably will not come down.

Meanwhile, green depends on supply of electrolysers, whose factories are still under construction, a process hard to rush. Its supply can ramp up only as fast as electrolysers can be obtained. Efficiency is still improving fast, so buying too many of the old, inefficient ones may also seem unwise. And, the cost of power to operate them is falling as solar and wind get cheaper.

At each of various production-cost points on the way down, more people will find it practical for them to use hydrogen at that price.

One simple step towards a solution would be to mandate green steel for government projects. Bridges, guard rails, buildings, snow plows, school busses, etc. You'd create a multi-billion dollar market instantaneously and have all the VCs and private equity folks piling into new research and development. That would help drive down the price for future non-governmental purchases.

Also, at a large enough scale, your concerns about makers steel products going out of business if they can't use high-emission steel go away. If the entire EU mandated it, or the US, it would still work.

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