Comment box Scope: summary, information Tone: neutral Opinion: just in analysis Sarcasm/humor: none Firebricks are a way to store thermal (heat) energy instead of converting it to electricity and...
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Scope: summary, information
Tone: neutral
Opinion: just in analysis
Sarcasm/humor: none
Firebricks are a way to store thermal (heat) energy instead of converting it to electricity and storing it in a battery. Thermal energy storage is really useful for things that specifically require heat, such as heating your home and various industrial manufacturing processes. It tends to use inexpensive materials and isn't that mechanically complex.
The article talks about its application in industrial heat in particular, which is a uniquely difficult part of the manufacturing supply chain to decarbonize. Producing steel and other materials just takes a lot of constant heat, and those furnaces require a ridiculous amount of energy, often at times that solar/wind aren't generating enough. Being able to store excess heat generation in firebrick thermal batteries could alleviate this problem and reduce carbon emissions in industrial processes.
Firebrick heat storage for industrial processes would substitute for about 14% of battery capacity worldwide by 2050 in a 100% renewable energy system, compared to a base case without firebricks, according to a study by Stanford professor Mark Jacobson and three Stanford colleagues.
Firebricks are made from common materials, and the cost of a firebrick storage system is less than one-tenth the cost of an equal-capacity battery system, the study says. Firebricks may be heated to high temperatures with external resistance heaters, while a type of firebricks that are electrically conductive may be heated with an electric current that dissipates heat.
The U.S. Department of Energy may provide up to $75 million to support two firebrick heat storage projects, saying the technology is “highly replicable.”
Firebrick systems powered by renewable energy could be used for up to 90% of industrial process heat applications, the Stanford study says. Meeting that demand in the U.S. would require a firebrick system capacity of 2.6 TWh, with a peak discharge rate of 170 GW.
Producing industrial heat with renewables would reduce industrial combustion emissions, which are currently 9.6% of U.S. all-sector emissions.
The study next uses an estimate from firebrick system developer Rondo Energy that the cost per kWh-thermal of a firebrick system will be about one-tenth the cost per kWh-electricity of a battery system.
I look forward to more developments like this in the future.
It's important for our governments to actively fund research and capital development for this sort of technology as soon as possible. Investment into green energy solutions was seriously boosted by President Joe Biden and the 117th Congress' 2022 Inflation Reduction Act. This legislation was only passed because constituents elected representatives who were interested in seeing real climate solutions fast. (Inflation has also been reduced to reasonable levels, though not really because of that act.)
I recommend that you vote for elected officials who will prioritize this sort of thing in the future. Voting for clean energy is good for our economy, our health, and the well-being of all living things on this planet.
I recommend that you do not cast a vote based on vibes. You should think about the track record your desired candidates have with clean energy, as well as the track record of their political party, to determine if they will actually try to do anything about this.
I also suggest that you get involved with advocacy in your local government to take advantage of the opportunities presented by legislation like the Bipartisan Infrastructure Law and the Inflation Reduction Act. It's important to work proactively with all your elected officials to encourage adoption of green energy systems locally and beyond.
Hey scroll_lock, I appreciate your consistency in excellent posts, and subsequent commentary. You seem to be very well informed, so I was hoping to get your thoughts on something A few of my close...
Hey scroll_lock, I appreciate your consistency in excellent posts, and subsequent commentary. You seem to be very well informed, so I was hoping to get your thoughts on something
A few of my close friends that are fairly well educated (all guys in our ~30’s) but very disillusioned with the current political landscape and therefore don’t participate in anything politics wise. I’m the sort to message all my representatives to voice my own beliefs and what I think should be supported, but getting them to is literally like pulling teeth. They think their opinion doesn’t matter and could not possibly have any impact (on local issues, and even national issues)
Have you ever encountered similar situations? If so, do you have advice or thoughts on how to convince people the said mentality?
I know corporations and super-PACs have way more money than I do, but I feel like if every single citizen voiced their beliefs that should at the end of the day outweigh these faceless donations (because then representatives could be voted out if they didn’t go along with the popular support)
I don’t really think that everyone would actually one day participate in politics, but I sure know it won’t be possible if I don’t try personally
Comment box Scope: comment response, advice Tone: neutral Opinion: yes Sarcasm/humor: none Yes, constituent apathy is a major problem in our society. One of the problems here is that people are...
Exemplary
Comment box
Scope: comment response, advice
Tone: neutral
Opinion: yes
Sarcasm/humor: none
Have you ever encountered similar situations? If so, do you have advice or thoughts on how to convince people the said mentality?
Yes, constituent apathy is a major problem in our society.
One of the problems here is that people are not taught how to effectively advocate, especially if they come from suburban areas where protesting is frowned upon as something poor, desperate, and disruptive people do. So they just sit at home and complain about problems and then obviously get disillusioned because nothing is changing. Well, gee! If the world fixed itself by itself, we'd all be living in palaces by now. Voting is great, but it's a bare minimum.
The other problem is that the media makes it seem like all important change happens at the federal level, and that the states do a couple things, and that local governments are just sort of there. This is backwards. All politics are local. In general, not only do local politics directly affect your life more than any other level of political rule, but they are also the most malleable and the most ignored. State politics are also quite important to local communities can also be influenced to some extent. Federal politics are indeed important, but they are more complex to influence and that is not where I would start as a budding advocate. A lot of federal advocacy tends to be done through state and local advocacy. For example, my state representative is really interested in acquiring federal funding for a new subway proposal, but only because local advocates and political leaders have engaged with him about it.
If you live in a smallish town, it is relatively easy to meaningfully influence major policy as an individual or group. The pool of people engaged in local politics is so miniscule that you could probably run for mayor or council and win on a good platform, even with no prior experience, as long as you can present yourself well. But you don't need to be a politician to control your community's destiny.
If you live in a largeish city, it is relatively more difficult to meaningfully influence major policy as an individual, but certainly not impossible, and it is pretty feasible as a group. It is still extremely feasible to influence what most people would consider "minor" policy, like micro-level infrastructure upgrades to certain intersections. Do enough of these projects and it becomes major. In any larger constituency, the processes to do that will always be a little more bureaucratic, but there is plenty of opportunity. You just have to learn how to navigate it.
Hierarchy of effective advocacy (roughly from most to least effective):
Personally being a local politician who has the literal legal authority to do things and influence legislative processes.
Personally being a ranking local civil servant who has broad discretion to do things and great insight into how things work. Can be an ally to non-government advocates.
Personally being a subordinate local civil servant who has limited discretion to do things, but great insight into how things work. Can be an ally to non-government advocates as well as a point of contact for advocate engagement with the agency.
Be part of a federally designated Regional Planning Commission or similar organization whose mandate is creating long-term visions and medium-term action plans for your region. For example, the Delaware Valley Regional Planning Commission in my city (Philadelphia) is responsible for much of how the region's infrastructure will be shaped in the next 50 years. State and local planners defer to a lot of these plans when doing more specific studies, though they can go further if they want.
Personally being a stakeholder or person of interest to a given local project, such as being the property owner of some vacant land that's part of a development scheme. The government must necessarily work with you to complete the project and you can influence it significantly.
Create, co-run, or otherwise meaningfully contribute to the operation of any sort of non-profit advocacy group, such as a 501(c)(3) or 501(c)(4) that advocates for transit access, pedestrian safety improvements, bicycle lanes and infrastructure, etc. These groups are distinct from neighborhood groups because they are issue-focused. Organized advocacy is by far the most effective method of advocacy. If your town/city doesn't have a local advocacy group... CREATE ONE!!! (I have personal experience registering 501(c)(3) and tangentially 501(c)(4) organizations from scratch, so I can help you navigate this process if you want, and/or put you in touch with others who have more experience. It costs a bit of money, but not really that much.) These groups can be the ones who "get everyone into a room together," including state officials, city officials, local neighborhood organizations, and others. Those meetings are essential to driving useful change.
Be on the Board (a decision-maker) of some sort of registered local neighbors association/community association, ideally a 501(c)(3), though sometimes they are just regular nonprofits which aren't tax-exempt. Politicians bend over backwards to serve organized community groups because they effectively act as a voting bloc. Most of these organizations have committees/subcommittees related to things like Vision Zero (if you care about traffic safety). If you're on the Board, you can be on these committees and significantly influence the direction of projects in the neighborhood. It takes some work though, and you have to actually care about being involved with your neighborhood in general, not just one little pet project.
Be very involved with these "issue-based" advocacy groups, even if you aren't responsible for running them. These groups are how you build a network of people who know stakeholders personally. These groups are how you keep up with what's happening. These groups are how you build coalitions. You can't do it by yourself. But being "part of" one of these advocacy networks is often as simple as joining a Slack/Discord server or a newsletter.
Be a voting member of one of the aforementioned registered community organizations. Membership eligibility is usually determined by your street address. You are probably eligible to join at least one such organization (maybe several, as their boundaries often overlap), especially if you live in a dense area, so look them up online and see if you can get involved. Even if you don't have capacity to be on the Board of one of these registered community groups, voting for people on the Board and in favor of useful projects is valuable. Doing things like collecting petitions from neighbors in favor of good projects can be extremely valuable. Taking the lead on such projects can be the difference between something being fixed and remaining broken. And some committees don't require you to be on the Board, depending on how the organization is structured, so you can still be engaged in that way.
Donating to local advocacy groups (in particular) and political campaigns. If you don't have the time to advocate, your financial support can make a big difference. For small groups, every dollar seriously counts. (But in my opinion most people have more free time and energy than they think. They just spend it all on their phones and that is very draining, so they feel too overloaded. But going to an advocacy meeting once a week is not hard or time-consuming. I think almost everyone on this website can do it.)
Attend scheduled city council sessions and committee sessions and voice your support for (or opposition to) specific bills. You can find bill information online. For example, in my city (Philadelphia), we use Legistar. Just keep track of when council meets and then follow the process to show up and support bills. If you can get a group of people to attend such meetings, especially a diverse group of people from many backgrounds, your city is particularly inclined to listen!
Protesting about something targeted, specific, and time-bound. Direct action is most effective when you make extremely clear 1) what the problem is and why it needs to be fixed, 2) who has the power to change it, 3) how those stakeholders can change it. Drumming up public support for straightforward, actionable improvements is meaningful because it establishes the narrative that this is a legislative or policy problem (which it almost always is) rather than some vague "issue" that just magically keeps showing up. Once you point out solutions, people get excited. And you want to get people excited about your advocacy. Specificity is what differentiates effective protestors from non-effective protestors.
Attending virtual public meetings to comment on proposals in your local area, such as municipal and state infrastructure plans. Typically, DOTs will contract out design work to a company or do some of it themselves and then present the findings in some sort of virtual forum a few years in advance. These meetings are typically not publicized well. If you can get a group of people to attend such meetings, you can bombard them with (useful, actionable) critiques and areas for improvement. The more different people are there, the more you can coordinate feedback and the more chance they will realize they are under scrutiny and make substantive changes. Since these meetings tend to be quite early in the process, there's a lot of opportunity for improvement. But make sure that your suggestions are constructive. Don't just complain about a problem: provide a solution. Do some of the legwork for them and it'll be easier for them to say yes.
Attending in-person public outreach meetings from state/local government agencies about projects. These are often coordinated with local registered community organizations/neighbor groups, so they tend to have a bit more visibility. By the time they're doing in-person outreach, most of the planning will already have been done, but there is still an opportunity to change a lot of the details. If there's significant community opposition to a particular part of a project, they may even go back to the drawing board! (In-person meetings are also an opportunity for you to meet city officials like planners, who can be useful contacts as an advocate.)
Personally call and email your local elected officials in support of legislation they are sponsoring or co-sponsoring, and encouraging them to support other legislation you like. Here's a tip: calling is usually more effective than writing. But if you can find a way to get their actual email address, instead of going though some online form, you are a lot more likely to get a response. The online forms are still valuable, they're just a little less likely to personally read that. In a smaller town, they may not have a secretary and may read all input no matter what format.
Publishing educated, informational material to a non-technical audience, such as issuing Right to Know requests to uncover local government communications and spending and distilling that information into a useful format. For instance, a request on communications in a specific timeframe on a specific topic between the city and a developer. You can do this with a blog. RTK requests are just one example and can benefit from some legal knowledge, but they can be very useful even as a non-lawyer. Other useful disseminations of information may be related to local candidate elections, barriers to transit-oriented development, etc. If you have a large audience, or if you're working on specific projects with advocacy groups, your impact can be a lot higher than it's shown in this list.
Identifying, researching, and theorizing actionable solutions to problems in your constituency. Most people literally just don't understand why problems occur where they live. If you know, it's a lot easier to determine how to proceed. For example, "Why are they cutting down this tree?" Well, because they planted the wrong kind of tree to begin with, the soil was too compacted, and they didn't give it enough space to grow. Oh—well, we can fix that going forward. Now we know!
Researching local candidates for election and voting for them. Local election turnout is extremely low, so the relative power of your vote is very high if you do turn up.
Protesting about something broad or vague. Direct action protests are often useful, but these ones tend to do a better job at building a community of advocates concerned about a set of issues than actually doing anything in particular.
Proactively searching for community meetings on upcoming projects, because government actors don't always do a good job of disseminating them, and sharing them with others, especially advocacy groups who would want to attend.
Signing up for mailing lists for your local government, for municipal agencies, and for state agencies (like your state's Department of Transportation) to keep up with planned projects, and sharing public news with others. Advocacy groups will already be doing this, but you can tell your less-involved friends and neighbors and get them excited! Maybe they will want to become advocates too.
Aimlessly complaining about problems to people you know. (Better than nothing, but not effective)
Thinking about problems and not telling anyone. (Not effective)
Ignoring problems because they don't affect you or you just don't care. (Not effective)
I have highlighted in bold some of the useful things that you can do as non-government workers to advocate for useful change in your local government. I have struck through some of the behaviors that your friends probably do that are obviously ineffective. As you can see, there are a lot of ways to be very effective that are within reach.
I include some things that aren't realistically going to apply to you and your friends, such as being politicians or owning land that's coincidentally important to a particular project. While you might not be the decision-maker about something, being able to identify the locus of power, i.e. the "stakeholders," in a particular project tells you exactly who you need to convince to get something done. As for the convincing, it's just a matter of identifying what those stakeholders find important and acting on those desires (written approval of some portion of constituents, the planting of a tree here or installation of a bollard there, some noise reduction issue, whatever).
As far as convincing your friends to do anything goes, I think you just have to get them interested in bite-sized issues and work on them together in order to empower them to do more advocacy by themselves. For example, bringing a friend to a community meeting about transit infrastructure can get them excited about new initiatives. But more effectually, going with a friend to a specific direct action protest being carried out by an advocacy organization and then having policy change as a result is super empowering. Even just talking about local plans is better than nothing.
I know corporations and super-PACs have way more money than I do
PACs (527-exempt organizations) can actually be a force for good. In my city (Philadelphia) I sometimes work with a political action committee called 5th Square. As a PAC, they are technically the same kind of "dark money" as the organizations in the news, but this is really just a mechanism to fund campaigns. "Urbanists" are people who care about improving the built environment, especially in terms of increasing the housing supply (and thereby lowering the cost of housing), reducing homelessess, promoting access to accessible public transportation, improving cycling and pedestrian access and amenities, and addressing traffic safety issues, among other things. Many urbanist groups are also interested in creating green spaces, planting trees, improving access to sanitation and addiction treatment, and otherwise qualitatively improving the experience of living. Equitable economic uplifting underpins this philosophy, though people have varying ideologies. Most urbanists are online a little too much and tend to be quite politically progressive, but the motives of the movement are generally palatable to most people who live in cities and towns, including more conservative people, and many of the solutions are palatable too.
Anyway, if you want to actually get anything done, you have to get a little dirty. Some people find PACs objectionable for donor disclosure reasons, because they are "dark money" and so on. I understand the hesitancy, but if the ultimate barrier between getting, say, a new train in your city and the car-centric status quo is a particular elected official who doesn't want it no matter how much outreach you do... electing someone else can often be the difference. Campaigns require funding, and PACs can deliver funding. They are in the tax code for a reason. You can generally get through to elected officials with enough time and effort, but the threat of them losing their seat is a motivation to actually listen to constituents, and being replaced by someone better is obviously a win for advocates.
It's also possible to use the system as it currently exists in order to elect people who want to reform the system.
I don’t really think that everyone would actually one day participate in politics, but I sure know it won’t be possible if I don’t try personally
Wow I don’t know where to begin. This was an incredibly well written post, and I wish I could more extensively respond to everything but three times now I’ve started and gotten distracted So...
Wow I don’t know where to begin. This was an incredibly well written post, and I wish I could more extensively respond to everything but three times now I’ve started and gotten distracted
So instead let me say I thoroughly appreciate the advice, and will be bookmarking this comment so I have some good places to start so I can make a difference where I live
OP, do you have a good technical overview how those high temperature storage systems work in practice? The article states This number is surprisingly high. It must include steel mills. Electric...
OP, do you have a good technical overview how those high temperature storage systems work in practice?
The article states
Firebrick systems powered by renewable energy could be used for up to 90% of industrial process heat applications
This number is surprisingly high. It must include steel mills. Electric arc furnaces regularly heat steel to 1800°C, but go as far as 3000°C for other alloys. We'll ignore the latter. But how do you heat a standard 80 ton furnace (normally pulling 60MW electric) from a fire brick storage system? How do you get the heat out of storage and into the furnace?
Is it all just 2000+°C (you want the transport medium to be a few hundred degrees above your target, otherwise you're barely moving any power around) nitrogen gas piped through ceramic pipes? The volumetric flow must be insane if you want to move tens or hundreds of MW (400 ton furnaces are not uncommon). How do you pump this flow? Ceramic fan blades? How do you get it into the furnace? Ceramic jacket? Use high temperature helium and pump it straight through the steel?
And steel is only the first thing. Cement kilns run at 1500°C.
Comment box Scope: comment response, information Tone: neutral Opinion: none Sarcasm/humor: none Chemistry is at the periphery of my expertise—I tend to talk about trains—but I can speak about...
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Chemistry is at the periphery of my expertise—I tend to talk about trains—but I can speak about what I know. Rosie Barnes, PhD has a very good video on Zero Emissions Heat Technologies for Industry, which I will be referencing. She has additional material on industrial heat and material production on her channel.
How do you get the heat out of storage and into the furnace?
Concentrated solar thermal plants can easily and consistently get industrial kilns to temperatures around 1000°C and above, and can at least briefly peak at 3000°C in advanced systems. For this energy to be usefully stored in a thermal battery, the battery must be able to maintain similar temperatures without melting. The storage of thermal energy in thermal batteries is efficient and does not introduce major losses like an electricity conversion could.
Thermal heat transfer can be accomplished through physical conduction (solids), convection (fluids), and radiation (electromagnetic waves). Barnes states that "radiation is the most effective, followed by convection, and then conduction."
Most thermal heat transfer systems I've heard about use some sort of heat transfer fluid in pipes to get the heat from the battery to the use. Air is one such fluid, though you can also use water and other substances.
Jacobsen et al describe the mechanics of firebrick systems in their 2024 paper linked in the article:
Heat-storing firebricks have high specific heats and densities so that they can absorb a lot of energy with little temperature increase, and they have high melting points. They are surrounded either by another type of firebrick that is more insulating, and then by steel to reduce heat loss further (15) or simply by a thick steel container (9). The process heat may be drawn from the firebricks on demand by passing ambient or recycled air through the channels in the bricks, yielding low-to-high-temperature air (15, 17), or it may be obtained from the emission of infrared radiation directly from the red-hot bricks (9).
In a heat storage enclosure, some firebricks may be used for heat storage and others, for insulation. Those used for storage should have a high specific heat, high density, and high melting point.
Firebricks have been applied previously for heat storage in heat regenerators used in glass making (22) and steel making (15). Regenerators are heat interchangers that receive heat from a high-temperature flue gas, store the heat for 20–30 min, then use the heat to preheat air for combustion. In this study, the heat may be stored for hours to days or even weeks. Even before 2018, firebricks, storing 10 MWh of heat, were deployed in China for commercial complexes and district heating projects (15).
Stack et al. (15) performed computational experiments with firebricks storing electricity as high-temperature heat (1,000–1,700 °C). The firebricks were arranged in a pattern and insulated. When heat was needed, it was transferred to a cold air stream, then used for either industrial processes or to reproduce electricity through a steam turbine. The study found that charging and discharging the firebricks could occur over a few hours, implying that systems of hundreds to thousands of megawatt-hours could be cycled daily.
Emphasis mine. The citations in that article would be useful to learn more about the engineering.
The volumetric flow must be insane if you want to move tens or hundreds of MW (400 ton furnaces are not uncommon). How do you pump this flow? Ceramic fan blades? How do you get it into the furnace? Ceramic jacket? Use high temperature helium and pump it straight through the steel?
If you're asking how regenerators/heat exchangers work on a mechanical level, my answer is "I don't know exactly." There will always be a natural tendency for heat to move from a hot place to a cold place. Technically, you can design a passive convection system that moves heat around by itself. This happens in the oceans. You can mechanically force your air fluid to move faster with blower and exhaust fans, but I don't know what physical configurations tend to work best.
For liquid systems you would use pumps instead of fans. Liquid pumps are old technology and well-understood. Some sort of centrifugal pump (radial flow pump) probably has the best volumetric flow rate. There are lots of other kinds of pumps, like various variations of positive displacement pumps, but I don't think they're suited for this use-case because they have more limited flow rates.
Radiative heat can provide additional delivery without the use of transfer fluids, but this is obviously dependent on space limitations.
I don't know enough about the material properties of specific fluids to comment on this in more depth, but it is possible to do all this without melting your equipment, at least up to about 2400°C in the case of pure low-grade solid carbon (graphite) firebricks. It's possible that future systems will be able to store and deliver heat at even higher temperatures.
Electric arc furnaces regularly heat steel to 1800°C, but go as far as 3000°C for other alloys.
Not all industrial heat requires such high temperatures. According to Barnes, who is much more of an expert than me:
Low-heat (150°C): chemical, food, and paper industries; drying, evaporation, pasteurization, baking, and sterilization
We tend to focus on the high-heat use-cases because they're particularly difficult to decarbonize. However, it's worth noting that low-heat and medium-heat processes still emit significant amounts of greenhouse gases. The split in absolute energy use, according to Barnes, is about 50/50.
In general, even if it's not feasible for these batteries to deliver 100% of the heat for a particularly high-temperature process at 3000°C, delivering a portion of that heat reduces the amount of greenhouse gas emissions needed to provide the rest of the heat.
Is anybody actually doing any of this?
Yes, but it's definitely a budding field. Some of the quotations I provided refer to real-world applications of this technology in commercial industry. This kind of technology is not yet economical in all cases, but it's technically feasible. That's one of the reasons I'm excited to read about new technologies and initiatives in industrial heat.
In the United States, Rondo Energy is probably the furthest along with firebrick thermal energy storage. They claim that their battery can store heat at temperatures up to 1500°C (presumably excluding delivery losses), which is pretty much what you need for a lot of cement, steel, etc. production. The research in Jacobsen's paper indicates that they can get much higher than that with better firebrick material chemistry.
IIRC the highest-temp startup doing this is using liquid silicon in graphite pumps (as in, graphite is the material the pipes and moving parts are made of) in a nitrogen atmosphere (so the...
Is anybody actually doing any of this?
IIRC the highest-temp startup doing this is using liquid silicon in graphite pumps (as in, graphite is the material the pipes and moving parts are made of) in a nitrogen atmosphere (so the graphite doesn't combust etc). It can hold up to 2400C (possibly more since graphite's melting point.is 3600C, but their experiments have only gone up to 2400C so far IIRC), which lets them target 1500C processes with a very comfortable delta of 900C.
A few quick thoughts since this is adjacent to what I study. Depending on the process you might not actually need your working fluid to reach 2000C+. Having high temperature stored heat would be...
A few quick thoughts since this is adjacent to what I study.
Depending on the process you might not actually need your working fluid to reach 2000C+. Having high temperature stored heat would be very useful for doing preheating which you then boost the rest of the way using electric systems. I'm not very familiar with most industrial high temperature processes, but a process that depends on drawing in material externally, heating it up, and then moving it somewhere else, using the stored heat in a preheat step would substantially reduce the peak energy demand needed for the final step of the process to get it the rest of the way to high temperature.
Much of this space is still very early stage, but there are a couple companies that are looking at storing the excess renewable electricity as high temperature heat and then converting it back to electricity through a traditional power cycle. Malta is one company doing this that jumps to mind and I think their round trip efficiency is 60-70% which is pretty good for electric -> heat -> electric. One pitch for this approach I've seen (not from Malta but I can't think of the other company right now) is allowing you to design a system that lets you discharge the storage as both electricity AND process heat. So you could potentially meet your low temperature process heat requirements with the storage directly and then meet high temperature process heat by converting the stored heat to electricity and then back to higher temperature heat in a furnace. Obviously that path way would be substantially less efficient, but it's not a far fetched idea.
Unfortunately, much of the energy in a furnace is not used for heating the metal, but for melting it. The enthalpy of melting is significantly higher than the heat capacity. But sure, there's...
a process that depends on drawing in material externally, heating it up, and then moving it somewhere else, using the stored heat in a preheat step would substantially reduce the peak energy demand
Unfortunately, much of the energy in a furnace is not used for heating the metal, but for melting it. The enthalpy of melting is significantly higher than the heat capacity. But sure, there's double digit percentage points of efficiency gains just in preheating the furnace and the charge.
round trip efficiency is 60-70% which is pretty good for electric -> heat -> electric
There is no way they're significantly past 50% for the heat-electricity step alone. They would make billions selling a 70% carrot efficiency process to classic thermal power plants.
At least in the case of Malta they're using Molten Salt as the working fluid and are heat pumping for converting the Electric to Heat in the first step. That's the only reason they're getting so...
At least in the case of Malta they're using Molten Salt as the working fluid and are heat pumping for converting the Electric to Heat in the first step. That's the only reason they're getting so high for a round trip efficiency. The heat pumping step moves heat between two storage tanks so they maintain the extra temperature gradient from the cold side. Then they reconvert to electric with a regular power cycle.
And certainly, the heat to electric step is probably in the 30-50% range. When I'd last talked to someone from the company two years ago that number was based primarily on modeling work. I haven't checked for news on their pilot project, but they were in the process of building a big grid-tied demonstration plant.
Antora is the other thermal grid storage company I was trying to think of. They seem to be trying to target industrial clients for their technology to combine heat and electricity storage. I think the round trip efficiency on theirs was also supposed to be somewhere around 60%. I think they super heat the storage blocks with resistance heat and then are recapturing the energy through infrared photovoltaics. A completely different approach than Malta, but they're going to much higher temperatures for their storage.
No, this is all about industrial process heat. I'm surprised, too. I guess I can see the potential in low temperature processes like food processing, and even mid temperature processes like...
No, this is all about industrial process heat. I'm surprised, too.
I guess I can see the potential in low temperature processes like food processing, and even mid temperature processes like chemicals production. But we use a whole lot of steel and concrete, and those run hot...
I wonder if it could be used for storing electricity as well? Sure, converting back to electricity is very wasteful. But if electricity is cheap in the first place, and storage is cheap and...
I wonder if it could be used for storing electricity as well? Sure, converting back to electricity is very wasteful. But if electricity is cheap in the first place, and storage is cheap and abundant, how much of a problem is it?
Comment box Scope: comment response, information Tone: neutral Opinion: none Sarcasm/humor: none Any kind of energy conversion introduces inefficiency, but it's not impossible. Ideally, you would...
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Any kind of energy conversion introduces inefficiency, but it's not impossible. Ideally, you would only want to do one conversion at the most. Going back and forth between electrical to thermal to electrical is more inefficient.
If there's a huge oversupply of cheap solar energy (or something like that), it's best to store it as electrical energy, but if it's cheap enough to produce then it can be economical to store it in a different format. The advantage of thermal batteries is that they're ridiculously cheap because they're mostly made out of rocks or sand.
According to Wikipedia, electrical to thermal energy conversions can have conversion efficiencies of 20% (in the case of a low-end refrigerator) to to ~100% (in the case of an electric heater). According to Wikipedia, the efficiency of a thermoelectric generator is like 5-8%, which is pretty abysmal. This is a little outside my area of expertise.
Rosie Barnes ("Engineering with Rosie") probably has a video about this.
Solar thermal power plants skip the electrical conversion process entirely and just store the sun's energy directly as thermal energy. This is useful for industrial purposes. Firebrick batteries and other cheap thermal batteries would be very useful paired with this sort of generating technology.
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Firebricks are a way to store thermal (heat) energy instead of converting it to electricity and storing it in a battery. Thermal energy storage is really useful for things that specifically require heat, such as heating your home and various industrial manufacturing processes. It tends to use inexpensive materials and isn't that mechanically complex.
The article talks about its application in industrial heat in particular, which is a uniquely difficult part of the manufacturing supply chain to decarbonize. Producing steel and other materials just takes a lot of constant heat, and those furnaces require a ridiculous amount of energy, often at times that solar/wind aren't generating enough. Being able to store excess heat generation in firebrick thermal batteries could alleviate this problem and reduce carbon emissions in industrial processes.
I look forward to more developments like this in the future.
It's important for our governments to actively fund research and capital development for this sort of technology as soon as possible. Investment into green energy solutions was seriously boosted by President Joe Biden and the 117th Congress' 2022 Inflation Reduction Act. This legislation was only passed because constituents elected representatives who were interested in seeing real climate solutions fast. (Inflation has also been reduced to reasonable levels, though not really because of that act.)
I recommend that you vote for elected officials who will prioritize this sort of thing in the future. Voting for clean energy is good for our economy, our health, and the well-being of all living things on this planet.
I recommend that you do not cast a vote based on vibes. You should think about the track record your desired candidates have with clean energy, as well as the track record of their political party, to determine if they will actually try to do anything about this.
I also suggest that you get involved with advocacy in your local government to take advantage of the opportunities presented by legislation like the Bipartisan Infrastructure Law and the Inflation Reduction Act. It's important to work proactively with all your elected officials to encourage adoption of green energy systems locally and beyond.
Hey scroll_lock, I appreciate your consistency in excellent posts, and subsequent commentary. You seem to be very well informed, so I was hoping to get your thoughts on something
A few of my close friends that are fairly well educated (all guys in our ~30’s) but very disillusioned with the current political landscape and therefore don’t participate in anything politics wise. I’m the sort to message all my representatives to voice my own beliefs and what I think should be supported, but getting them to is literally like pulling teeth. They think their opinion doesn’t matter and could not possibly have any impact (on local issues, and even national issues)
Have you ever encountered similar situations? If so, do you have advice or thoughts on how to convince people the said mentality?
I know corporations and super-PACs have way more money than I do, but I feel like if every single citizen voiced their beliefs that should at the end of the day outweigh these faceless donations (because then representatives could be voted out if they didn’t go along with the popular support)
I don’t really think that everyone would actually one day participate in politics, but I sure know it won’t be possible if I don’t try personally
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Yes, constituent apathy is a major problem in our society.
One of the problems here is that people are not taught how to effectively advocate, especially if they come from suburban areas where protesting is frowned upon as something poor, desperate, and disruptive people do. So they just sit at home and complain about problems and then obviously get disillusioned because nothing is changing. Well, gee! If the world fixed itself by itself, we'd all be living in palaces by now. Voting is great, but it's a bare minimum.
The other problem is that the media makes it seem like all important change happens at the federal level, and that the states do a couple things, and that local governments are just sort of there. This is backwards. All politics are local. In general, not only do local politics directly affect your life more than any other level of political rule, but they are also the most malleable and the most ignored. State politics are also quite important to local communities can also be influenced to some extent. Federal politics are indeed important, but they are more complex to influence and that is not where I would start as a budding advocate. A lot of federal advocacy tends to be done through state and local advocacy. For example, my state representative is really interested in acquiring federal funding for a new subway proposal, but only because local advocates and political leaders have engaged with him about it.
If you live in a smallish town, it is relatively easy to meaningfully influence major policy as an individual or group. The pool of people engaged in local politics is so miniscule that you could probably run for mayor or council and win on a good platform, even with no prior experience, as long as you can present yourself well. But you don't need to be a politician to control your community's destiny.
If you live in a largeish city, it is relatively more difficult to meaningfully influence major policy as an individual, but certainly not impossible, and it is pretty feasible as a group. It is still extremely feasible to influence what most people would consider "minor" policy, like micro-level infrastructure upgrades to certain intersections. Do enough of these projects and it becomes major. In any larger constituency, the processes to do that will always be a little more bureaucratic, but there is plenty of opportunity. You just have to learn how to navigate it.
Hierarchy of effective advocacy (roughly from most to least effective):
Aimlessly complaining about problems to people you know.(Better than nothing, but not effective)Thinking about problems and not telling anyone.(Not effective)Ignoring problems because they don't affect you or you just don't care.(Not effective)I have highlighted in bold some of the useful things that you can do as non-government workers to advocate for useful change in your local government. I have struck through some of the behaviors that your friends probably do that are obviously ineffective. As you can see, there are a lot of ways to be very effective that are within reach.
I include some things that aren't realistically going to apply to you and your friends, such as being politicians or owning land that's coincidentally important to a particular project. While you might not be the decision-maker about something, being able to identify the locus of power, i.e. the "stakeholders," in a particular project tells you exactly who you need to convince to get something done. As for the convincing, it's just a matter of identifying what those stakeholders find important and acting on those desires (written approval of some portion of constituents, the planting of a tree here or installation of a bollard there, some noise reduction issue, whatever).
As far as convincing your friends to do anything goes, I think you just have to get them interested in bite-sized issues and work on them together in order to empower them to do more advocacy by themselves. For example, bringing a friend to a community meeting about transit infrastructure can get them excited about new initiatives. But more effectually, going with a friend to a specific direct action protest being carried out by an advocacy organization and then having policy change as a result is super empowering. Even just talking about local plans is better than nothing.
PACs (527-exempt organizations) can actually be a force for good. In my city (Philadelphia) I sometimes work with a political action committee called 5th Square. As a PAC, they are technically the same kind of "dark money" as the organizations in the news, but this is really just a mechanism to fund campaigns. "Urbanists" are people who care about improving the built environment, especially in terms of increasing the housing supply (and thereby lowering the cost of housing), reducing homelessess, promoting access to accessible public transportation, improving cycling and pedestrian access and amenities, and addressing traffic safety issues, among other things. Many urbanist groups are also interested in creating green spaces, planting trees, improving access to sanitation and addiction treatment, and otherwise qualitatively improving the experience of living. Equitable economic uplifting underpins this philosophy, though people have varying ideologies. Most urbanists are online a little too much and tend to be quite politically progressive, but the motives of the movement are generally palatable to most people who live in cities and towns, including more conservative people, and many of the solutions are palatable too.
Anyway, if you want to actually get anything done, you have to get a little dirty. Some people find PACs objectionable for donor disclosure reasons, because they are "dark money" and so on. I understand the hesitancy, but if the ultimate barrier between getting, say, a new train in your city and the car-centric status quo is a particular elected official who doesn't want it no matter how much outreach you do... electing someone else can often be the difference. Campaigns require funding, and PACs can deliver funding. They are in the tax code for a reason. You can generally get through to elected officials with enough time and effort, but the threat of them losing their seat is a motivation to actually listen to constituents, and being replaced by someone better is obviously a win for advocates.
It's also possible to use the system as it currently exists in order to elect people who want to reform the system.
This is the right attitude. Good on you!
Wow I don’t know where to begin. This was an incredibly well written post, and I wish I could more extensively respond to everything but three times now I’ve started and gotten distracted
So instead let me say I thoroughly appreciate the advice, and will be bookmarking this comment so I have some good places to start so I can make a difference where I live
Thank you!!!
OP, do you have a good technical overview how those high temperature storage systems work in practice?
The article states
This number is surprisingly high. It must include steel mills. Electric arc furnaces regularly heat steel to 1800°C, but go as far as 3000°C for other alloys. We'll ignore the latter. But how do you heat a standard 80 ton furnace (normally pulling 60MW electric) from a fire brick storage system? How do you get the heat out of storage and into the furnace?
Is it all just 2000+°C (you want the transport medium to be a few hundred degrees above your target, otherwise you're barely moving any power around) nitrogen gas piped through ceramic pipes? The volumetric flow must be insane if you want to move tens or hundreds of MW (400 ton furnaces are not uncommon). How do you pump this flow? Ceramic fan blades? How do you get it into the furnace? Ceramic jacket? Use high temperature helium and pump it straight through the steel?
And steel is only the first thing. Cement kilns run at 1500°C.
Is anybody actually doing any of this?
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Chemistry is at the periphery of my expertise—I tend to talk about trains—but I can speak about what I know. Rosie Barnes, PhD has a very good video on Zero Emissions Heat Technologies for Industry, which I will be referencing. She has additional material on industrial heat and material production on her channel.
Concentrated solar thermal plants can easily and consistently get industrial kilns to temperatures around 1000°C and above, and can at least briefly peak at 3000°C in advanced systems. For this energy to be usefully stored in a thermal battery, the battery must be able to maintain similar temperatures without melting. The storage of thermal energy in thermal batteries is efficient and does not introduce major losses like an electricity conversion could.
Thermal heat transfer can be accomplished through physical conduction (solids), convection (fluids), and radiation (electromagnetic waves). Barnes states that "radiation is the most effective, followed by convection, and then conduction."
Most thermal heat transfer systems I've heard about use some sort of heat transfer fluid in pipes to get the heat from the battery to the use. Air is one such fluid, though you can also use water and other substances.
Jacobsen et al describe the mechanics of firebrick systems in their 2024 paper linked in the article:
Emphasis mine. The citations in that article would be useful to learn more about the engineering.
If you're asking how regenerators/heat exchangers work on a mechanical level, my answer is "I don't know exactly." There will always be a natural tendency for heat to move from a hot place to a cold place. Technically, you can design a passive convection system that moves heat around by itself. This happens in the oceans. You can mechanically force your air fluid to move faster with blower and exhaust fans, but I don't know what physical configurations tend to work best.
For liquid systems you would use pumps instead of fans. Liquid pumps are old technology and well-understood. Some sort of centrifugal pump (radial flow pump) probably has the best volumetric flow rate. There are lots of other kinds of pumps, like various variations of positive displacement pumps, but I don't think they're suited for this use-case because they have more limited flow rates.
Radiative heat can provide additional delivery without the use of transfer fluids, but this is obviously dependent on space limitations.
I don't know enough about the material properties of specific fluids to comment on this in more depth, but it is possible to do all this without melting your equipment, at least up to about 2400°C in the case of pure low-grade solid carbon (graphite) firebricks. It's possible that future systems will be able to store and deliver heat at even higher temperatures.
Not all industrial heat requires such high temperatures. According to Barnes, who is much more of an expert than me:
We tend to focus on the high-heat use-cases because they're particularly difficult to decarbonize. However, it's worth noting that low-heat and medium-heat processes still emit significant amounts of greenhouse gases. The split in absolute energy use, according to Barnes, is about 50/50.
In general, even if it's not feasible for these batteries to deliver 100% of the heat for a particularly high-temperature process at 3000°C, delivering a portion of that heat reduces the amount of greenhouse gas emissions needed to provide the rest of the heat.
Yes, but it's definitely a budding field. Some of the quotations I provided refer to real-world applications of this technology in commercial industry. This kind of technology is not yet economical in all cases, but it's technically feasible. That's one of the reasons I'm excited to read about new technologies and initiatives in industrial heat.
In the United States, Rondo Energy is probably the furthest along with firebrick thermal energy storage. They claim that their battery can store heat at temperatures up to 1500°C (presumably excluding delivery losses), which is pretty much what you need for a lot of cement, steel, etc. production. The research in Jacobsen's paper indicates that they can get much higher than that with better firebrick material chemistry.
IIRC the highest-temp startup doing this is using liquid silicon in graphite pumps (as in, graphite is the material the pipes and moving parts are made of) in a nitrogen atmosphere (so the graphite doesn't combust etc). It can hold up to 2400C (possibly more since graphite's melting point.is 3600C, but their experiments have only gone up to 2400C so far IIRC), which lets them target 1500C processes with a very comfortable delta of 900C.
A few quick thoughts since this is adjacent to what I study.
Depending on the process you might not actually need your working fluid to reach 2000C+. Having high temperature stored heat would be very useful for doing preheating which you then boost the rest of the way using electric systems. I'm not very familiar with most industrial high temperature processes, but a process that depends on drawing in material externally, heating it up, and then moving it somewhere else, using the stored heat in a preheat step would substantially reduce the peak energy demand needed for the final step of the process to get it the rest of the way to high temperature.
Much of this space is still very early stage, but there are a couple companies that are looking at storing the excess renewable electricity as high temperature heat and then converting it back to electricity through a traditional power cycle. Malta is one company doing this that jumps to mind and I think their round trip efficiency is 60-70% which is pretty good for electric -> heat -> electric. One pitch for this approach I've seen (not from Malta but I can't think of the other company right now) is allowing you to design a system that lets you discharge the storage as both electricity AND process heat. So you could potentially meet your low temperature process heat requirements with the storage directly and then meet high temperature process heat by converting the stored heat to electricity and then back to higher temperature heat in a furnace. Obviously that path way would be substantially less efficient, but it's not a far fetched idea.
Unfortunately, much of the energy in a furnace is not used for heating the metal, but for melting it. The enthalpy of melting is significantly higher than the heat capacity. But sure, there's double digit percentage points of efficiency gains just in preheating the furnace and the charge.
There is no way they're significantly past 50% for the heat-electricity step alone. They would make billions selling a 70% carrot efficiency process to classic thermal power plants.
At least in the case of Malta they're using Molten Salt as the working fluid and are heat pumping for converting the Electric to Heat in the first step. That's the only reason they're getting so high for a round trip efficiency. The heat pumping step moves heat between two storage tanks so they maintain the extra temperature gradient from the cold side. Then they reconvert to electric with a regular power cycle.
And certainly, the heat to electric step is probably in the 30-50% range. When I'd last talked to someone from the company two years ago that number was based primarily on modeling work. I haven't checked for news on their pilot project, but they were in the process of building a big grid-tied demonstration plant.
Antora is the other thermal grid storage company I was trying to think of. They seem to be trying to target industrial clients for their technology to combine heat and electricity storage. I think the round trip efficiency on theirs was also supposed to be somewhere around 60%. I think they super heat the storage blocks with resistance heat and then are recapturing the energy through infrared photovoltaics. A completely different approach than Malta, but they're going to much higher temperatures for their storage.
Are we sure it's not simply about heating buildings? Steel and cement sound like science fiction. Hope I'm wrong, though.
No, this is all about industrial process heat. I'm surprised, too.
I guess I can see the potential in low temperature processes like food processing, and even mid temperature processes like chemicals production. But we use a whole lot of steel and concrete, and those run hot...
I wonder if it could be used for storing electricity as well? Sure, converting back to electricity is very wasteful. But if electricity is cheap in the first place, and storage is cheap and abundant, how much of a problem is it?
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Any kind of energy conversion introduces inefficiency, but it's not impossible. Ideally, you would only want to do one conversion at the most. Going back and forth between electrical to thermal to electrical is more inefficient.
If there's a huge oversupply of cheap solar energy (or something like that), it's best to store it as electrical energy, but if it's cheap enough to produce then it can be economical to store it in a different format. The advantage of thermal batteries is that they're ridiculously cheap because they're mostly made out of rocks or sand.
According to Wikipedia, electrical to thermal energy conversions can have conversion efficiencies of 20% (in the case of a low-end refrigerator) to to ~100% (in the case of an electric heater). According to Wikipedia, the efficiency of a thermoelectric generator is like 5-8%, which is pretty abysmal. This is a little outside my area of expertise.
Rosie Barnes ("Engineering with Rosie") probably has a video about this.
Solar thermal power plants skip the electrical conversion process entirely and just store the sun's energy directly as thermal energy. This is useful for industrial purposes. Firebrick batteries and other cheap thermal batteries would be very useful paired with this sort of generating technology.