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Electrically conductive bricks can replace fossil fuels in industrial processes

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Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#31

Post by szvsw »

audunw wrote: post #30

Yeah, this is why I’m not too worried about the energy storage side of going 100% renewable energy in a scenario where we also decarbonise completely. 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…

> 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).

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.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#32

Post by hagbard_c »

DoctorOetker wrote: post #22
kukkamario wrote: post #5

Earlier quoted context omitted.

Well it is just a brick that can acts as a heating element. In terms of converting electricity to heat it is almost 100% efficient like every other electric heating element. 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.

> In terms of converting electricity to heat it is almost 100% efficient like every other electric heating element. 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.

That is not in any way related to the theoretical efficiency of resistance heating and not really of any help here unless there is some working fluid which allows for the temperatures needed for industrial processes. It might be possible to recuperate process heat if a suitable working fluid can be found which evaporates at the temperature of the product leaving the process chamber and condenses at a temperature suitable for (pre-)heating the process chamber. I have not heard of such though.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#34

Post by klyrs »

tofof wrote: post #33

They're not very conductive if they're getting 1800 degees hot when you pass current through them.

Every material is a conductor in a high enough potential! And if you pass enough current through copper, it can get to the same temperature, provided you're careful enough to maintain contact after it melts.

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?

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#35

Post by yetihehe »

s1artibartfast wrote: post #29
Retric wrote: post #28

Earlier quoted context omitted.

How exactly are you going to CHEAPLY collect and store energy for a 1400+C process using solar thermal? 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.

Maybe I dont understand. If your primary goal is thermal storage, why do you care about the peak temperature? If we are talking primarily about storage, what are the advantages of a PV field + 1400 C brick storage vs parabolic + 500C storage?

Higher temperaure = more energy stored in the same material. Simple as that. When you have a process requiring 400C for reasonable effiency, your storage actually starts to count from above 400C, so if you have 500C storage, you only have effectively 100C of usable tmperature difference stored in your bricks.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#36

Post by s1artibartfast »

yetihehe wrote: post #35
s1artibartfast wrote: post #29

Earlier quoted context omitted.

Maybe I dont understand. If your primary goal is thermal storage, why do you care about the peak temperature? If we are talking primarily about storage, what are the advantages of a PV field + 1400 C brick storage vs parabolic + 500C storage?

Higher temperaure = more energy stored in the same material. Simple as that. When you have a process requiring 400C for reasonable effiency, your storage actually starts to count from above 400C, so if you have 500C storage, you only have effectively 100C of usable tmperature difference stored in your bricks.

If it is cheaper to store at 1400 than 500, then that is an argument for doing so. Higher temperature is not a justification in its own right, absent economic benefit. It is also the case that conduction losses are proportional to heat, and it brings many other challenges as well.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#37

Post by IshKebab »

DoctorOetker wrote: post #22
kukkamario wrote: post #5

Earlier quoted context omitted.

Well it is just a brick that can acts as a heating element. In terms of converting electricity to heat it is almost 100% efficient like every other electric heating element. 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.

> In terms of converting electricity to heat it is almost 100% efficient like every other electric heating element. 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.

Heat pumps are not heating elements.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#38

Post by Retric »

s1artibartfast wrote: post #29
Retric wrote: post #28

Earlier quoted context omitted.

How exactly are you going to CHEAPLY collect and store energy for a 1400+C process using solar thermal? 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.

Maybe I dont understand. If your primary goal is thermal storage, why do you care about the peak temperature? If we are talking primarily about storage, what are the advantages of a PV field + 1400 C brick storage vs parabolic + 500C storage?

> If your primary goal is thermal storage

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.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#39

Post by Retric »

s1artibartfast wrote: post #36
yetihehe wrote: post #35

Earlier quoted context omitted.

Higher temperaure = more energy stored in the same material. Simple as that. When you have a process requiring 400C for reasonable effiency, your storage actually starts to count from above 400C, so if you have 500C storage, you only have effectively 100C of usable tmperature difference stored in your bricks.

If it is cheaper to store at 1400 than 500, then that is an argument for doing so. Higher temperature is not a justification in its own right, absent economic benefit. It is also the case that conduction losses are proportional to heat, and it brings many other challenges as well.

Chemical processes don’t occur at any temperature. So the ideal storage temperature depends on the goal temperature and a bunch of other factors.

The argument for storing at 1500C could be 500C is useless not just worse economically.

Re: Electrically conductive bricks can replace fossil fuels in industrial processes

#40

Post by amelius »

klyrs wrote: post #34
tofof wrote: post #33

They're not very conductive if they're getting 1800 degees hot when you pass current through them.

Every material is a conductor in a high enough potential! And if you pass enough current through copper, it can get to the same temperature, provided you're careful enough to maintain contact after it melts. 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…

> And if you pass enough current through copper

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.

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