Hacker News Reader

Comment by SoftTalker | Hacker News Reader

> A solarfarm would be upgraded to a power plant that generates electricity all day. That's it.

That's it, but that would be incredibly valuable, as the big downside of solar is that it only works during the day, and only really works for the peak part of the day, maybe 6-8 hours depending on where you are.

The question will be is this process to store solar energy as methane cheaper (bottom line, i.e. accounting for losses in turning it back into electricity later) than storing it in batteries.

View on HN

Some countries (Germany) need a way to store enough energy for several _weeks_ of consumption. This is prohibitively expensive for batteries.

What approaches to storage are viewed a as most promising? Is Germany building anything out yet or testing at scale?

In general, from my own efforts to try to understand the answer to that question, pumped hydro storage is probably the most promising but it'll only work in places that have the geography for it. There are a couple of excellent examples in Scotland, https://en.wikipedia.org/wiki/Cruachan_Power_Station is one. The trick is that there's a 400m drop; lots of places won't have the geography to get that much head.

In Germany? So far it has been mostly magical thinking. It has almost infinite capacity

Realistically, long-term hydrogen storage is the only technology that is even remotely feasible. There are several demonstrator projects ongoing right now. I'm personally not too optimistic about them.

Germany has been the biggest exporter of electricity in the world in 8 of the last 10 years. Germany also has one of the most reliable grids in the world in terms of system interruptions - as measured by SAIDI - with less than 15 minutes of interruption per customer year - significantly more reliable than France for example. They've managed to keep the lights on after going completely cold turkey on Russian gas in the space of less than a year - a remarkable feat which has been given no credit by most German energy policy critics who have been confidently predicting energy Armageddon in such a scenario.

Not to say that there are no grounds for criticizing German policy but most of the criticism seems to be politically motivated rather than based on specific failures of the policy.

Secondly, why hydrogen? It's a potent greenhouse gas - GWP100 of 12 or 13 times that of CO2. Yes it's less potent than methane but it's far "leakier" and more difficult to contain than methane as well as being more dangerous and difficult to handle. It cannot be combusted in air (most are suggesting mixing it with methane) in a domestic setting because of the 10 times as much NOx caused by the higher burning temperature. While all the infrastructure for methane/natural gas already exists including long term (seasonal) storage facilities, I see no compelling reason to spend 100s of billions to build all this new infrastructure to use a different warming gas for energy storage and transport.

To be honest it's a minor issue in the grand scheme of things - keeping natural gas around to cover the last 10% of electricity generation is no big deal as the world rushes to electrify the other activities which currently release large amounts of CO2. The focus should be on getting to that 80-90% carbon-free electricity and the electrification of as much as is possible of pollution sources like domestic heating/cooking, transport and heavy industry.

> Germany has been the biggest exporter of electricity in the world in 8 of the last 10 years.

Sure. The good old coal power plants and natgas turbines are extremely reliable and capable.

As for Germany being an exporter, Sweden and Norway both have recently declined to expand their interconnects with Germany. They don't want their local markets to be swamped by cheap low-quality power during the summer, and then squeezed during the winter when German renewables are greatly diminished.

> Not to say that there are no grounds for criticizing German policy but most of the criticism seems to be politically motivated rather than based on specific failures of the policy.

The specific failure of the policy is simple. Germany's power is DIRTY. And it's not getting any better.

> Secondly, why hydrogen?

Because there are no alternatives. Power-to-methane is going to be about 3-4 times more expensive than pure hydrogen. And again, this is not my personal preference, but the official policy of the German state.

> To be honest it's a minor issue in the grand scheme of things - keeping natural gas around to cover the last 10% of electricity

It won't be 10%, more likely 30% once Germany switches to electric heating and EVs. This switch right now is being held back by horribly high energy cost.

It’s difficult to respond to someone who claims that “Sweden and Norway both have recently declined to expand their interconnects with Germany. They don't want their local markets to be swamped by cheap low-quality power during the summer,”

Elections carrying electricity do not have the quality of being “cheap” or “low quality”. If you’re convinced that there is some measurable difference between an electron produced by a hydro-power turbine and one from a coal plant, then I don’t think we have any basis for further discussion.

> Sweden and Norway both have recently declined to expand their interconnects with Germany.

Sorry. Just reporting the news: https://www.reuters.com/business/energy/swedish-government-s...

> Elections carrying electricity do not have the quality of being “cheap” or “low quality”.

They do. Because electrons, that are forced to move by the wind, cease moving when there's no wind. And this happens for weeks at a time in winter in Germany.

There's a fix for that: capacity markets. In essence, if you can guarantee that your source of electrons will always be available, you get paid for that. Europe has pledged to "do something" about that EU-wide by 2028.

Good point, any country at high lattiudes will need this during the winter.

I don't see why? Germany is part of one of the biggest most diverse synchronised electricity grids in the world - it sits at the centre of an international transmission system stretching from Ireland to Turkey and from the artic circle to Morocco. Germany has no need to store several weeks of electricity when it can just tap its neighbours when it needs to. In reality, generally Germany has been a net exporter of electricity.

> Germany is part of one of the biggest most diverse synchronised electricity grids in the world

Germany needs about 300GW in winter once it switches to electric heating and EVs. In winter, renewables regularly drop to about 10% of their average production for weeks at a time. So Germany will need to import about 250GW of power from its neighbors. That also need power for their own use.

This is just not feasible.

So the plan right now is to replace the coal generation with natural gas generation, and color the pipes in green paint. Oh, and make the companies to pinky-promise that they are "hydrogen ready".

Covestro, a German company, already has a signed contract and made advance payments to receive the equivalent of up to 100,000 tonnes of green hydrogen (GH2) per year commencing 2025.

    A kilogramme of hydrogen - the unit most often used – has an energy value of about 33.3 kWh.[1] So a tonne of hydrogen delivers about 33 MWh and a million tonnes about 33 terawatt hours (TWh). To provide a sense of scale, the UK uses about 300 TWh of electricity a year.

~ https://www.carboncommentary.com/blog/2021/6/11/some-rules-o...

It takes a good while to build out the physical infrastructure to deliver green hydrogen equivilants:

    Green hydrogen is made from renewable energy, producing zero pollution – its only by-product is steam. FFI’s ambition is to grow its green hydrogen production to 15 million tonnes of green hydrogen per year by 2030, accelerating to 50 million tonnes per year in the next decade thereafter.

~ https://fortescue.com/news-and-media/news/2022/07/05/fortesc...

The person doing this isn't in the "pinky promise" game, they built out a penny stock company from 2c a share to ~$28 a share over two decades to capture a large chunk of a billion tonne per annum raw iron ore market.

> The person doing this isn't in the "pinky promise" game, they built out a penny stock company from 2c a share to ~$28 a share over two decades to capture a large chunk of a billion tonne per annum raw iron ore market.

Yeah, swindling governments is a profitable business.

You’re criticizing German for not already having the capacity in place to meet a future demand? It’s not enough that Germany is currently a huge net exporter?

“So the plan right now is to replace the coal generation with natural gas generation, and color the pipes in green paint.” - eh no. This is not “the plan” although getting rid of all coal is part of the plan.

> This is not “the plan” although getting rid of all coal is part of the plan.

It is: https://www.reuters.com/business/energy/germany-agrees-subsi...

> The ministry said hydrogen transition plans should be drawn up by 2032 to enable the plants to be fully switched to hydrogen between 2035 and 2040.

> "Germany last year agreed with the European Commission to tender 8.8 GW of new hydrogen plants, and up to another 15 GW that will run initially on natural gas before being connected to the hydrogen grid by 2035 at the latest, but Berlin and Brussels have disagreed on how the gas plants would be subsidised."

So basically, Germany is _paying_ companies somewhere around $20B to build new gas power plants and make _plans_ to switch to hydrogen by 2032. The switch itself can go into 2040-s.

Winter and wars are why.

Reply on news.ycombinator.com