51–60 of 107 posts
When I was a child, we would play a game called "the floor is lava". It's a simple game: you have to get around, but not touch the floor. Jumping on the furniture and such. Fine for a pastime, when you're small, but to get places, you use the floor. A certain faction of the project to decarbonize the electrical grid likes to play a similar childish game: "nuclear power is lava". It causes them to come up with whimsic…
Earlier quoted context omitted.
I suspect in the next 50 years electricity will end up globally transportable via undersea cables, like the internet does for data today. At that point, it's always summertime somewhere and it's always daylight somewhere, and if prices were to fall to zero there is always someone who would like more heat for something. Therefore I suspect zero-priced energy will stop existing.
Isn't it possible that such a system will over-produce 99% of the year and that therefore, the marginal cost will almost always be $0? 'Take my energy and allow me to stop accelerating my flywheels which regulate production' seems more plausible than 'someone would always like more heat for something' (what?) Or possibly 'take my energy and I'll cut off some of the people using spare energy to do low priority, low va…
You can imagine home appliances having an 'eco' setting which runs the appliance like the washing or the dishwasher at the cheapest time in the next 12 hours.
Or the water heating systems which heat more water when prices are cheap.
Or heaters which switch between natural gas and heat pump based on price.
Or electric car chargers which charge during the cheapest hours.
(all of these already exist, but none are yet common).
Over the long term there is also plenty of elasticity. If electric heating is expensive, people will install gas/oil heaters when they renovate. If electricity is cheap, more people buy electric cars. With cheap electricity, maybe fewer people decide to add more insulation to their houses. Businesses don't upgrade energy inefficient equipment to be more energy efficient, etc.
Plenty of demand elasticity in both the short and long term. End result: As long as the market is unconstrained, prices won't hit zero more than say ~5% of the time.
At scale, what I don’t get is this requires a lot of energy to kickstart the reaction (heating the iron ore to 400 degrees). Where is that energy coming from when energy production is constrained in winter. Or would the plan be to slowly heat over fall?
Even most internal-combustion engines require energy stored in a battery to kickstart them, so this is not different. Obviously the energy efficiency of this process based on iron is modest. It is likely that the energy efficiency is even lower than for the process of storing energy by making synthetic hydrocarbons (e.g. synthetic gasoline), which are much easier to use once energy is stored in them. The only advanta…
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The article says they're currently powered from a grid connection but hope to be fully solar powered soon. What I'm not getting is how this process produces more energy than the solar input to power the process. Unless they're getting solar collectors to try to generate 400 degree temperatures rather than PV solar to electricity, but that seems like a sketchy proposition at best in winter.
It does not, but they are storing the energy for winter. Solar produces a lot more energy in summer, which is especially true in Switzerland or Europe in general.
Unfortunately, I don't see this making any sense for large scale energy storage. Storage tanks for compressed hydrogen enjoy the square-cube law. The larger they are the less expensive they are proportional to the mass of hydrogen they hold.
With this iron oxide method, you need 27 tons of iron oxide for one ton of hydrogen. You can procure right now tanks that can hold 2.7 tons of hydrogen and weigh 77 tons empty [1], the ratio is 28 to 1. But the round-trip efficiency of the tank is virtually 100%. The efficiency of the iron-based storage is only 50%. The tanks are not very expensive.
I can't see the niche that this idea can apply to.
[1] https://www.iberdrola.com/press-room/news/detail/storage-tan...
The vast, cheap power that photovoltaic will provide is a giant opportunity. Please review the links below
https://terraformindustries.com/
Terraform industries converting sun and air into natural gas:
https://techcrunch.com/2024/04/01/terraform-industries-conve...
The solar industrial revolution is the biggest investment opportunity in history:
https://caseyhandmer.wordpress.com/2024/05/22/the-solar-indu...
This is a pretty elegant idea. It takes 826 kJ to split a mole of iron oxide (Fe2O3) and it takes 855 kJ to split 3 moles of water (H2O). So if you take H2 and blow over one mole of Fe2O3 you can strip the O3 for the cost of 826 kJ but then by burning the hydrogen in oxygen you get 855 kJ, for a net exothermic effect of 29 kJ, which is a rounding error. The opposite reaction requires 29 kJ, again negligible, there ar…
The energy density of the system is surprisingly high (in my modest perspective). It looks like 800kWh per ton of iron. Isn't it ~five times as much as the batteries we have in cars?
I've seen claims up to 300 Wh/kg for batteries, but yes this is still more than that.
And for good batteries their density doesn't really matter.
Sodium ion batteries will be fantastic grid storage simply because they're just going to be dirt cheap