Hacker News Reader

Comment by aenis | Hacker News Reader

It's happening in the Netherlands over the last two weeks as well. Many days where there are a few hours during which energy is either free or you get paid to consume it. (Taxation still makes it hard to turn profit - each consumed kWh is taxed at 0.15c regardless). Basically, if there is sun and wind, energy is very cheap.

View on HN

This guy keeps track of it nicely, 75 hours with negative prices so far this year:

https://nitter.net/BM_Visser/status/1660605197142351875#m

Consumers can sign up for dynamic electricity price to get the benefits (and risk a huge bill like in Texas last year): https://enever.nl/grafieken-stroomprijs-vandaag-morgen/

This is false, Griddy waived the bills:

https://www.cbsnews.com/news/griddy-energy-charged-9000-powe...

They're still risking getting a huge bill. Hoping your risk gets mitigated by a company trying to avoid bad PR isn't a gamble I would take.

Too bad there's no infrastructure in place for producing synthetic fuel with the surplus electricity. It might not be efficient, but if we're producing surplus electricity anyway, then even inefficient storage/usage won't be a waste.

Compared to any (currently practical) storage, just laying more wires to places that don't currently have too much wind/sun is much more efficient.

Turns out, cables are relatively cheap, compared to batteries.

How cheap are international cables compared to electrolysis for hydrogen production paired with lorries for transport?

The conversion ratio is quite bad, however if you MUST burn something (like in Steelmaking mentioned in the sibling comment) then it starts to make more sense but iirc it's still calculated to be slightly more expensive steel compared to coal currently (but if we continue building out variably producing power like wind, solar while augumenting the regular production the general idea is that the intermittent spikes could be used for affordable production).

Honestly, wasting the energy is cheap compared to batteries.

It's okay to waste excess capacity so long as it is wind/solar/nuclear.

Absolutely! Alas, the Finnish administration seems more interested in using areas with cheap electricity to attract electricity-intensive industry rather than, say, exporting it to other countries. Heck, in neighbouring Sweden they have issues transferring power from the large hydro dams in the north, to the densely populated south where the power is needed.

While building better grids is practically doable, I don't see it happening anytime soon; the idea, of using cheap electricity to entice a FAANG to build a data center in one's backyard is preferable to most elected officials here.

In that situation it's probably better business to just buy cheap electricity off the market and use it to do something useful.

Over longer distances the transmissions losses makes cables more inefficient (otherwise all of Europe could easily be powered by Saharan solar-power). The flooding mentioned in the article is about 1000km away from the major population centers in Finland and Sweden.

Transforming to burnable fuels via electricity is actually useful for some applications and actually in the planning stage with some steelmakers (as a replacement for coal!) like h2 green steel in the same region of Sweden as the floodings. They claim that steelmaking is up to 7% of global co2 emissions and being able to move to gas produced with cheap electricity might be only marginally more costly than coal.

https://www.h2greensteel.com/

Not necessarily. For a worked example, it's cheaper to power Boston with a large number of local solar panels and batteries than it is to power it with a small number of solar panels and batteries in Arizona connected to Boston via HVDC lines.

https://caseyhandmer.wordpress.com/2020/12/27/the-future-of-...

Why would we produce synthetic fuel when we have batteries? We also have other ways to store electricity.

Am I missing sarcasm in your comment or something?

Batteries (lithium particularly) are not storage devices. They're grid stabilising devices. They are simply not able to store meaningful quantities of energy at an affordable price. In our city, we are installing a battery that can power 160k homes for 2h, at the cost of AU$200m. That's just not "storage", it's designed to flatten out peaks and troughs in supply.

The batteries are not cost efficient, and take up lots of space. Not great for the Northern Europe - expensive land, strict zoning laws, etc.

Gasoline has an energy density like 100x batteries. As an energy storage medium, it's excellent.

The thousand pounds of batteries in a Tesla contain the same amount of energy as ~3 gallons of gas.

This. It, along with diesel, is also the power source for most wheeled veichles in current operation on the planet.

I'm sure EV's is going to take over in most areas given enough time. Until then, it's only logical to run ICE's on green fuels if available. Synthetic fuels made with excess solar/wind certainly sounds like it would fit that description.

Also, we already have infrastructure in place for handling large amounts of petrol and diesel, so storage and handling is a solved problem.

How many gallons of gas need to be burned to account for the entire lifespan of that battery?

My point is that when talking about storing excess energy from the grid, maybe storage density isn't as important as storage availability.

Cost of storage is the big question. Synthetic fuels might have bad efficiency. But building huge container for liquid or gas is not expensive.

Let's say you want to store fuel now and keep it for 6 months, might be realistic with gas or fuel. On other hand single cycle from battery is awfully expensive. Even if you get to use it for 100 years.

Let's say it takes n batteries to store electricity produced one day and use it the next day. Then it takes 10n batteries to store electricity produced during ten days and use it during the next ten days.

With synthetic fuel let's say it takes m fuel producers / consumers to store electricity produced one day and use it the next. Then it still takes m fuel producers / consumers to store electricity produced during ten days and use it the next ten days. The only thing you need to scale up is your fuel tank, but that is very cheap.

The problem is any plants that would be producing synthetic fuel, fertiliser, etc would all be operating 100% of the year. They wouldn't be an "on demand" plant - the economics wouldn't support it (mostly due to capex).

With excess wind/solar, pumped hydro would be the storage mechanism, but that clearly doesn't apply when a country has an excess of hydro too!

I’m guessing they are referring to liquid hydrogen fuel production. Are those plants so expensive to setup that they have to run 24/7 to make up their investment? Lots of articles say it might eventually be economical, like https://inl.gov/article/using-excess-energy-to-split-water-c....

There’s several thresholds here. Something that operates 50% of the time can mostly limit things to cheap power. Something that’s viable operated 10% of the time can always get cheap power.

Do you have any examples of this? I've never come across any major capital project that wasn't designed for 85%+ uptime (and the downtime was simply for maintenance)

A lot of infrastructure isn’t 100% 24/7 even if it gets regular use. Subway systems both shut down for much of the day but they also operate well below maximum rush hour capacity.

Many factories, office buildings, and even stores spend the majority of the day/week empty or very close to it.

Below that you have schools which often close for several months a year.

Entertainment venues even multi billion dollar sports stadiums may spend a lot of time empty. Where possible they aim for year round operations, but often it’s not viable.

Below that you have peaking gas electric power plants, as many grids pay for reserve capacity that’s very rarely used. Some extreme cases might not even be used beyond validating it still works in a given year.

Sure but all of these use cases are entirely different to a production plant, say an oil refinery.

A synthetic fuel refinery can operate 24/7, so would be budgeted to do so.

I could potentially see a hydrogen "battery"/electrolysis setup absorbing excess power in an affordable way, but I'm just saying to date I haven't seen a single one.

Ahh, I was going for Major Capital project.

The closest thing to a low utilization fuel refinery is probably some desalination plants. Very high energy costs + wild demand swings means some shutdown quite a bit.

There is a few some hydrogen manufacturing plants which only operate on very cheap renewable electricity. However, as I understand it those are currently operated as relatively inexpensive test facilities.

Gas peaker plants don't run all that often.

I was thinking more in the line of e-Fuel and the like: https://en.wikipedia.org/wiki/Electrofuel

But sure, if hydrogen can be used, stored and then consumed then I can't see why it couldn't be a good idea, assuming demand. The thing about making petrol and diesel is that there's a guaranteed demand for the product, assuming the price is right.

Or a country that doesn't have enough unserviced demand spikes to make pumped hydro useful.

Many industrial processes have a high capital cost. If you build a plant that can make synthetic fuel, you don't want it sitting idle 70% of the time. If the plant is extraordinarily cheap capital-wise, then you are ok to use if for load balancing. But the usual suspects (aluminum smelting, water desalination, production of synfuels) don't qualify. Maybe making hydrogen via electrolysis qualifies, but then you have a storage and transportation problem. Still, I think hydrogen is probably the best use case for cheap but intermittent electricity.

Edit: I misread. Sub cent tax makes a lot more sense :)

The tax is 0.15 euros / kWh?! That's higher than my total rate (amortized connection fee, per kWh cost, taxes)!

In Finland, sadly, it's closer to 2 cents. And in my particular part of the country distribution is charged at a further 5, plus VAT. Plus 30Eur/Month connection flat fee.

How little do you actually pay for electricity?

For the last 3 months my total (connection charge, per kWh, taxes) was:

- April: $70 for 635 kWh. USD$0.110/kWh

- March: $71 for 570 kWh. USD$0.124/kWh

- February: $79 for 650 kWh. USD$0.121/kWh

That looks significantly higher than 0.0015€/kWh.

I'm dumb. I misread that as a 15 cent tax. Not sub cent.

I pay €0,394/kWh (Tax included, Netherlands). That price does not include fixed connection costs (0,19 per day) and a bunch of other things.

Prices are insane here. The provider will pocket the money they make off of cheap production of energy. Us consumers will see nothing of the low electricity price.

How is that affecting the ROI of people that invested in Solar at home?

Reply on news.ycombinator.com