Finland has inaugurated an industrial-scale sand battery this week in the southern town of Pornainen, where it'll take over heating duties from an old woodchip power plant for the municipality. It's set to reduce carbon emissions from the local heating network by as much as 70%, and is the largest…
This isn’t a battery, it’s a Thermal Energy Storage (TMS). Just because it stores energy doesn’t mean it is a battery.
The sand is heated up electrically, and energy is stored thermally. They don’t even yet have a system for converting that stored thermal energy into electricity again, it’s just used to heat water.
‘Battery’ is the name for any device that stores any energy. It doesn’t have to be electric energy.
Seebeck generators exist.
Language is funny sometimes. Battery used to refer to a collection of individual electric cells, ‘a battery of cells’ that worked together to supply the required voltage. Old cell tech was such low voltage, that several cells were required to juice itself to practical voltages for working purposes. Here the word was a mot emprunté - borrowed, from the military where battery was a term to describe a functional group of artillery that worked together for improved function. The military stole the old french term battre, ‘to beat’.
Eventually “battery” evolved to mean electric power storage device regardless of cell construction. Now apparently it also includes thermal charging, storage and discharging, even when only a single cell.
Language is weird. The proper term would be accumulator, but weirdness reigns supreme.
IIRC Battery also used to refer to a collection of cannons
Uh, didn’t I just say that? Lol
The thing is, it didn’t evolve that way. Battery is a technical term with a defined meaning. Colloquial use by people ignorant of it cannot change the technical definition, because technical definitions are not set colloquially like most language is.
Saying it evolved that way is like saying “windmills” generate electricity. The term is wrong, and anyone doing anything meaningful in that industry knows they’re not mills, they’re wind turbine generators, or turbines. People might know what you mean when you use the wrong term, but that doesn’t make your term in any way correct.
Last I heard Seebeck generators weren’t that good/practical for large scale use; did things change?
No, but they exist.
Turbines are still kings in thermoelectric generation.
Being king as having huge losses, but unfortunately it is the best we got
Sure, and windmills generate electricity and high voltage is anything above 30V.
People say a lot of nonsense, particularly when they’re adjacent but not really a part of a technical field.
A “battery” is a multiple of some kind of module. You can have a “battery” of Anti-Aircraft guns. In electrics, a battery is made up of multiple cells, and these cells are made of two metals inside an electrolyte.
This is not multiple modules of anything, and this is not made up of metals and electrolytes. This is not a battery.
Edit: Also, your wiki link literally starts with (my emphasis):
Did we read the same wiki page? It really doesn’t start that way. In fact, the words “Electric Battery” don’t even appear on that page.
My bad, I had multiple wiki tabs open and got confused which one it was. I was quoting from the wiki on batteries, which the above wiki links to when it says an energy store “is generally called an accumulator or battery”.
So, at best, the wiki citation given by the user above cites another more technical wiki that immediately states the opposite of what’s being claimed.
Electric batteries are defined as a number of cells, made of electrolyte and metal contacts, arranged together to form a “battery” of cells. An electric battery is a type of energy storage device.
A “sand battery” is also an energy storage device, but meets neither the definition of “electric battery” or the general definition of “battery” as it is not a multiple of some unit. Thus it is not a battery. The only way it is a battery is as a marketing term.
Yes, and the basic principle of thermal batteries has been quite common here in Finland for some time.
All Finnish cities have district heating networks, so there is some heating plant that generates heat, which is distributed to homes using water as medium. It is closed system where hot water goes in, colder water comes out, which is heated back up. This energy is used to heat the home and heat the cold usage water (faucet/shower etc)
Because the network is lots of water, there is already quite a lot of energy storage in the heat grid itself, so itself works as a battery. In last five years almost all big networks have created water based thermal batteries. Those are 7-8 stories high insulated water containers. These make sense because you just start taking the already heated water from the container to the grid when ever you need.
So the tech itself is quite standard here, just the medium of using sand is new. Sand brings you bit longer storage time, but adds bit of complexity to the process.
Source: I work in a company that owns these kind of networks
I’m not knocking the tech, I’m criticising the article for getting the terminology completely wrong. Moreso, the manufacturer has even fewer excuses.
Maybe there’s a language thing here, but in English battery is not the appropriate term for this. “Battery” really refers to just a bank of some multiple of something. Originally it was naval weapons and then in electrics it was multiple cells of electrolyte. An electric battery is a specific type of energy storage, this is a different type: thermal energy storage or TES.
Hell, on the grid you don’t even refer to battery electric storage as batteries that much, the common term is BESS - Battery Energy Storage System.
Yes, I totally agree, when talking about these thermal batteries, it should always be made clear.
When Converting heat MWh(t) to electricity MWh(e) is pretty much 2/3 loss in the process, i.e. turbine, and it must be super heated vapor meaning like 800C°.
Edit: But to be clear, they are called heat batteries, even in English.
They’re called batteries, but they’re not batteries, by definition. They’re called batteries mainly for marketing, I imagine.
However on the grid in English speaking countries they will refer to them differently. Probably TES or TESS, as it goes nicely with BESS (Battery Energy Storage System), which is the common industry name for grid scale electric batteries. Furthermore, in that sector it’s necessary to have clear distinction, as different types of generation have different characteristics.
Source: am HV electrical engineer.