@yoatman

Why do you make comments without having the least idea about the technologies involved?

The most favourable areas with ample solar and wind resources are miles from anywhere, which is why the land is cheap.

There is no way of even using the power without turning it into a chemical of some sort, so the choice you are presenting does not exist.

And as the energy authorities in every country of the world realise, decarbonisation simply can't take place without hydrogen, which is why it is such a big part of all their plans

Light vehicle transport is just one small part of the puzzle, and it is ludicrous to pretend that batteries can tackle much of the rest.

@yoatmon stated: "Energy produced from renewables is a too valuable resource to be wasted in H2 infrastructure. "
Reply: RE is used directly in the grid or stored in batteries whenever possible, and only the grid-surplus RE will be used to make H2.
Grid electricity is only 1/3 to 1/4 of total energy consumption, so we will need to overbuild RE capacity to be 5 times higher than the grid's peak demand to meet all energy demand. As such, we will have grid-surplus energy for the majority of the time, except when RE output will be down to 1/5 of peak output. During which time, ALL of the RE output will be devoted to the grid. When RE output is below grid's demand, then gas turbines will have to be turned on burning H2 as fuel, but this is a rare event, due to the overwhelming RE capacity.

Notice that due to the rare event of the grid needing power backup, grid-utility battery storage will NOT be cost-effective due to infrequent cycling. Battery need to be cycled every 1-2 days in order to use up all of its cycle life during its limited shelf life of 10-20 years.

This is dispatchable demand scheme to take advantage of intermittency of RE in order to require very little grid-utility storage and very little wasteful use of H2 to generate electricity.

Please note that for industrial use and for heating purposes, H2 has efficiency near 100%. New higher-temp steam electrolysis has efficiency of 90% on HHV basis even when accounted for the heat input, so we will have 90% round-trip efficiency, to rival any other e-storage media, comparable with battery's efficiency.

For light vehicles, Plug-in FCV that can use grid electricity for 80% of total mileage will overcome the inefficiency of FCV, and only needing H2 for long trips. For Heavy-duty vehicles for long-distance, the use of H2 permit significant gain in payloads over the use of battery. Short-trip HDV can be battery powered.

In summary, judicious use of RE which involves direct grid use, battery storage, and H2 for industrial and heating purposes and for long-trips in vehicles will make the most out of valuable RE resources. The true answer is the word AND instead of EITHER or OR, in the case of RE.

Don't believe all you hear about H2:
https://cleantechnica.com/2020/12/18/big-oil-is-fueling-the-hydrogen-rush/

@Lad

How is your fight against those fake moon landings going?

You simply ignore the bits of reality you don't fancy.

Falling costs for renewables are a fact.

Falling costs for electrolysers are a fact - you can buy them right now way cheaper than a decade ago.

Mixing hydrogen in NG pipelines for delivery and extracting it where needed are also facts.

Hydrogen storage is orders of magnitude cheaper than batteries, and the notion that batteries alone can do the job of enabling renewables at high penetration rates is a fantasy.

Roger,
hydrogen for heating is the most preposterous use one can imagine.

Option A: use a heat pump, with a positive COP which can give you up to 2 units of heat for each unit of electricity
Option B: bring an hydrogen pipe (with all its problems) to your home, burn 1 unit of heat which took nearly 2 units of electricity to synthesize.

I cannot imagine any rational being choosing Option A.

Even where a heat pump can't work, simple resistive electric heat is much better than hydrogen! Better efficiency without the expensive installation.

@peskanov

That is because you are utterly ignorant of the figures behind the engineering proposals, and prefer imaginary non-solutions.

The electricity does not appear by magic, and if you want a high proportion of renewables in the grid it has to be stored as chemical energy to cope with its periodicity.

So Japan now has 300,000 home fuel cells running on natural gas, where the heat from reforming the gas to hydrogen to produce electricity is used for heating water, so having an overall efficiency of over 90% for thermal plus electrical, an increase in efficiency of natural gas use of around 30% against central generation and transmission.

Real engineering plans as opposed to fantasy move on from that to allow a greater proportion of hydrogen in the natural gas grid, so that for instance in the UK by 2025 all gas boilers are to be compatible with 100% hydrogen.

Hydrogen also provides for year round 100% renewably powered blocks of flats in northern latitudes for instance in Sweden and integrates just fine with home solar, heat pumps and so on.

Here are the UK's plans out to 2035, when much of the grunt work has to be done to enable zero in 2050:

https://www.theccc.org.uk/publication/sixth-carbon-budget/

If you want to critique those plans, let us see a detailed, numerical rebuttal of the relevant criteria

You are fantasising.

Get in touch with reality.

@peskanov

'That electricity is much better spent using it directly, no matter if we are talking about cooking or heating.'

Sure.

So stick to fossil fuels.

If you want to use renewables, it is not available when you want it and needs storing.

That is 'why hydrogen'

You must imagine that all the engineers in all the energy authorities in the world who universally are leveraging hydrogen to enable a lot of renewables are morons.

' I have seen plenty of them through the years '

And obviously understood none of them.

The 'alternative' you suppose does not exist.

Show me the plan, with the numbers to decarbonise without using hydrogen.

There isn't one, from any energy authority anywhere.

I would like to question their color spectrum. I seems to me that the most "green" source of hydrogen would be high temperature electrolysis using nuclear power as it uses less electric power. And I would suggest that using renewable power would be no different that no different than the yellow grid power electrolysis unless you truly had an excess of renewable power and even then it would still make more sense to use the nuclear power as it is more efficient.

@yoatman::

I welcome alternative number based analysis.

The issue is that there aren't any, just random battery good, hydrogen bad burblings without the least analysis of how to make a low carbon society work without extensive use of hydrogen.

That is why all the real engineering proposals are based on that.

sd:

Hydrogen makes the economics of nuclear a lot better, as although modern reactors can be powered down, when their costs are mostly build not fuel, it makes little sense to do so.

China is looking at HT electrolysis for their new reactor builds.

I have always, or at least for the last half century and more, been a nuclear guy, and in my estimation the use of hydrogen is an enabling technology in conjunction with nuclear, and in no way opposed.

And the nuclear wastes will be served to our children and grandchildren for supper?

I believe every word that you have written. I trust you more than the pope and Trump will be venerated for centuries as a saint of the 21st century.