Between this and the newer co2 reduction technologies in kilns we might be close to finding ways to build combined steel and cement factories that have massively reduced greenhouse gas emissions.
If you want to do that you'd be better off using parabolic mirrors to heat regular fire bricks directly.
These are unique it seems because they're durable electric heating elements that can hit industrial process temperatures and might be cheaper then alternatives?
You can also easily move electrical power long distances but parabolic mirrors are hard to integrate into existing industrial processes and locations. PV electricity is competitive with fossil fuels even if you ultimately just want heat.
Solar thermal is far more viable for low grade heat. Especially as energy storage is fairly trivial.
There are no moving parts in PV or these bricks, which means they'll have near-zero maintenance costs.
Also I'm pretty sure solar thermal can't heat steel - it relies on steel pipes throughout the entire system.
Very clever!
It's fun to compare and contrast strategies, as startups explore and define the problem space.
For example:
Fourth Power is a heat to electricity solution. It uses graphite bricks (up to 2400°C), liquid metal for plumbing, and thermophotovoltaic cells.
https://gofourth.com/our-technology/
Electrified Thermal Solutions is an electricity to heat solution. It combines the heating element, storage, and exchanger into a single brick (up to 1800°C).
I'm wondering if anyone has done the math for a cement plant in the southwest surrounded by PV solar.
Typically, but may no longer be true with renewables. I don't think any of solar pv, wind, and hydro generates significant heat in the process of their power generation.
Storing energy as heat is dead simple, cheap, can let you store huge amounts of energy, and you can store for fairly long timespans.
It doesn’t matter that you can’t feed power back to the grid (well, maybe you can.. you can convert the light given off the heated block with photovoltaics.. but that won’t be a huge factor). If we decarbonise industrial heat it will create enough demand for renewables that the minimum output of renewables (over a larger area, I think it’s fair to assume some grid improvements over the next years) will be more than enough to cover base load needs. We will probably have quite a lot of batteries for frequency regulation and smoothing out the duck curve. Some of that will also help with dunkelflaute. But mainly there will just be so much renewables that the output never goes below what is needed on a given day.
There’s so many aspects of decarbonisation that makes balancing the grid easier. Electric cars is another example, where a lot of people will have flexibility of delaying or being proactive with charging based on electricity price forecasts. I expect most rental car companies will provide some grid balancing services, and in the near future you’ll have to pay extra to check out a car with 100% SoC.
I didn't spot any mention of voltage requirements for that so maybe it requires so high voltage that cause it to be a bit harder to actually use.
- Heat pumps typically achieve better than 100% efficiency, though at modest temperatures (slightly above ambient room temperatures), and would be better suited to most space-heating applications.
- The key achievement of the described technology is very high temperature applications, such as metals smelting, though what advantages the described tech has over existing electric arc furnaces (utilising graphite electrodes, cheap and abundant and capable of 3,000 °C temps) is less than clear.
except there are many types of heat pump in this world that routinely achieve well above 100% efficiency, since pumping heat from a cold heat bath to a hot one can cost significantly less energy than generating that heat resistively.
The distinguishing feature to call these "conductive" is that you could make a kiln of these bricks and ordinary bricks, and the current should preferentially pass through the conductive ones. Some of the current will leak through every other available path, including the air, but that's true of every circuit in existence. Vacuum isn't supposed to conduct, but vacuum tubes pass current through it, don't they?
Yeah, but how do you make a copper wire heat up without also heating up the wiring that leads to that copper wire? You can make it thinner, but these bricks aren't very thin.
FWIW there are a few other comments in this page discussing TPV (albeit briefly) and there are at least a few companies seriously pursuing it with federal support. It is a pretty interesting alternative to other forms ESS, particularly for long duration (ie more relevant for critical resiliency applications than supply/demand arbitrage). Like you said probably will not end up super relevant in the grand scheme of the grid’s total ESS capacity, but it will most likely have a niche I think.
> I expect most rental car companies will provide some grid balancing services, and in the near future you’ll have to pay extra to check out a car with 100% SoC.
Rental car companies are an interesting example I hadn’t thought of before - thanks for highlighting that. Another more common challenge/opportunitu will be campuses - eg universities, large corporations, etc which have their own microgrid (often a CHP/district system in the northeast at least) - which may have a large number of commuters arriving in the morning and potentially wanting to charge their EVs all day. In 15 years, this might represent a pretty significant increase in demand, and represents giving a pretty substantial amount of free electricity to commuters (if things stayed as they are today). At the same time, charging up all of those vehicles during midday and then sending them home to immediately discharge when they plug in at 5-7pm could substantially abate the duck curve, and being an even larger further savings for the commuter. Seems obvious that some sort of new agreements/contracts etc will come in to play for these sorts of campuses.
Don't get me wrong, it would be super cool if someone creates a heat pump that can bring the temperature up enough to melt iron ore at greater than 100 percent efficiency, but it does not seem like anyone currently making heat pumps considers this remotely possible.
That’s the historical reason, but now it's used because carbon is a reducing agent that binds to oxygen, preventing it from oxidizing the iron back into iron oxide and because the coke is used as a permeable membrane to let the resulting gasses escape.
If it was just a matter of heat, there's any number of cleaner fuels steelmakers could use but they can't because the coal serves an important role in the chemistry of blast furnaces.
Induction cooktops are ridiculously efficient at heating
You've probably seen multiple instances of this in your daily experience. A fuse is a thin conductor between thick electrodes. A light bulb is a very fine conductor between thick electrodes, encapsulated in a vacuum bulb. If you use tungsten electrodes, you can easily melt copper in the manner I've described -- that's how TIG welders work.
Responding to your question about electric current:
Quite simply, use leverage! Take a transformer with multiple (N) windings on the primary and a single winding on the secondary. Putting one (DC) amp through the primary will induce N amps through the secondary. With induction, you can use a low current to induce high current. Or correspondingly, transform low (AC) voltage to high voltage -- this is how high voltage power lines work.
That doesn't make sense. Why would anyone use them instead of the more efficient alternatives? For artistic reasons?
>They only need to be cheaper than (IMO inevitable) carbon tax penalties plus the cost of these bricks compared to current methods, which is a rapidly falling curve.
this clearly indicates OP suggests they will become de facto cheaper once the traditionally externalized costs of environmental impact are accounted for.
The comparison is between this and carbon free solar-thermal for energy storage. Saying it doesnt have to be cheaper than solar-thermal simply isnt true.
It seems like an huge advantage to use an 80% thermal setup vs a 22% efficient panel, but we gave up on solar power towers for a bunch of reasons. With PV things are a lot more straightforward because you can reach nearly any temperature at equal efficiency.
If we are talking primarily about storage, what are the advantages of a PV field + 1400 C brick storage vs parabolic + 500C storage?
Grandparent:
> These are unique it seems because they're durable electric heating elements that can hit industrial process temperatures and might be cheaper then alternatives?
Storage usually makes less sense, but depends on capital cost per kW-hr right? No idea on the economics of that, but an electric heater can get hotter than solar thermal and use much less space at the point of use.
They are durable electric heating elements that can get hotter than solar thermal and hit industrial temperatures without using fossil fuels to heat locally with fire.
IF you just want to go electricity>heat>electricity Industrial Arc furnaces can go to 2000 C (and much higher but they have no industrial need).
I would love to be wrong.
I think the idea here is to go electricity->heat-storage->heat-usage, using the heat storage to take advantage of cheap renewables that might be otherwise curtailed and to buffer the heat to provide reliability for whatever process it is used for.
Almost any form of energy storage other than heat (i.e. batteries, hydrogen, gravity) would be far more expensive in that use case. By comparison, bricks are an incredibly cheap way to store heat.
If packaged correctly this could also be useful for uses like ovens at industrial bakeries, which have highly predictable energy use patterns.
Another example of a big application for time-shifted heating is domestic hot water heating with heat pump water heaters (or even resistance water heaters if the electricity is cheap enough). At least one company (https://www.harvest-thermal.com/) is taking this further to also provide space heating by time-shifting heat, again using water as the energy storage technology.
The goal isn’t thermal storage the goal is to do something that needs extreme temperature.
You can’t melt steel at 500C, you can melt it in bricks at 1500C that then cool to 1400C. Use electricity to heat a brick to 1500C and you get 100C worth of energy storage. Use solar thermal to get to 1400C and you get zero energy storage.
Im skeptical that they would be improvement on other forms of grid power storage.
This is independent of the question if they are good for melting steel.
I guess I dont understand the point you are advocating for.
The total energy storage is also unlikely to be huge so it’s more like load management not really grid storage. https://en.wikipedia.org/wiki/Load_management IE: Because we have energy storage and other users don’t we can cut demand when prices spike. Utilities will cut special rates for companies that allow the utility to load shed them first.
The same basic concept is common in other areas. Get enough storage for ~free such as with an EV and you can simply wait until prices get cheap before charging.
The argument for storing at 1500C could be 500C is useless not just worse economically.