The simplest energy storage solution is your hot water heater. Turning on everyone's hot water heater when there is surplus electricity, and turning them off when there's a deficit, is a very low cost solution.
The next level is using residential HVAC systems the same way. Comfortable temperatures are a range, so heating/cooling can push the temps to one end of the range, and when there is less electricity available, they can drift to the other end.
The charger for your electric car is another very practical sink for cheap electricity.
This is accomplished by having a spot price for electricity, and then people buying thermostats that query the spot price and turn HVAC, hot water heater, car battery chargers, etc., on and off.
This can be extended EVEN FURTHER by heating/cooling a pile of rocks to later use to heat/cool the house.
A battery consisting of a pile of rocks can't be expensive.
The idea is to not only adjust supply to the demand, but to shape the demand to the supply.
I am utterly astonished that this is never, ever discussed when talking about solutions to fluctuating supply. Having fixed electricity rates 24/7 is simply madness in today's electricity generation situation.
The problem with your great ideas, and "great ideas"generally is the lack of proven numbers.
As the poster above you pointed out the capacity of LI batteries is tiny. Yet you tout car batteries as though that were a new idea and a meaningful solution. And you ignore the fact that if you use car batteries as storage for the grid, that detracts from their use to, you know, run cars.
You also ignore the losses from your solutions. What is the round trip loss from heating up rocks and getting the energy back? It is huge. And you artfully forgot to mention all the equipment needed to get the energy back out in usable form such as electricity.
All the books and studies talk about load shaping, contrary to your "astonishment" that no-one is considering this "brilliant idea". The problems with load shaping are many. If you shut a factory down to spare the grid, then it is not producing. So all else being equal, you need more factories for the same production. Building and maintaining those extra factories takes labor, management, and energy.
Getting people to turn off air conditioning means that they are less comfortable, or perhaps unable to sleep, or unable to work. The South of the US more or less became viable economically due to air conditioning.
This is not unique to you, but I am really fed up with people spouting half-assed ideas and thinking that they constitute a solution.
As they said in the dot.com era - ideas are cheap.
> What is the round trip loss from heating up rocks and getting the energy back? It is huge. And you artfully forgot to mention all the equipment needed to get the energy back out in usable form such as electricity.
If you store the energy by heating the rocks, you can recover it to heat your house by simply blowing air over the rocks. No need to convert it to electricity, which would indeed be silly.
The same goes for air conditioning. Excess electricity could be used to cool the rocks, which then can be used to cool your house when electricity is expensive.
The detour through the rocks (or anything with thermal mass) costs next to nothing.
I am not talking about using the EV battery to run the house. I am talking about using the EV battery to run the EV. Simply charge it when electricity rates are cheaper. It's shifting the demand.
> thinking that they constitute a solution
They are perfectly and cheaply implementable, and are part of the solution.
> half-assed
I actually have a degree in mechanical engineering. You shouldn't be so hasty in your inferences.
I don't understand the animus in replies to your post. It's as if people want to deny that people like myself heat our homes in the winter by blowing air over hot water in a heat-exchanger. We can and many do heat that water during the day with the magic of the sun's rays or by burning wood (the only true renewable we have). Humans have been using thermal property of rock (not concrete, concrete doesn't match rock's efficiency) and water to heat ourselves and our homes for hundreds of years, and will likely continue to do so for hundreds more.
> The South of the US more or less became viable economically due to air conditioning.
I don't think that's the right way to phrase it. The South was clearly economically viable before A/C. It's kinda like saying that New York City wasn't economically viable until the invention of the safety elevator.
Overall I agree with your views on "half-assed ideas". I want to elaborate on this one topic a bit more, because it presses a button of mine.
On thing A/C did was make it possible to build cheap homes following northern tastes and styles, on the assumption power would remain cheap. Northerners could move in without having to adapt their customs and practices much.
Southern vernacular architecture includes high ceilings (so the heat rises above the people), lots of windows (to let the air go through and heat escape), and with the house raised off the ground (so cooling air flows underneath). This describes the A/C-less Florida house I grew up in. An even more traditional design would have a wraparound porch, to provide extra shade and let the windows stay open even when it rains.
OTOH, A/C encouraged house designs which require A/C to be comfortable - a sort of co-dependency. These vernacular features make the A/C bill higher, so they weren't included in newer homes. I tried living in a Florida home designed for A/C, but without using the A/C. Not only was it much less comfortable, as you write, but we started getting mold because of the humidity. A house made for A/C doesn't have much air flow.
So I don't think the argument is simply 'getting people to turn off air conditioning', but 'getting people to design houses which are a better fit for the local climate and have better long-term sustainability.'
That's of course hard, and expensive.
It's also hard to change lifestyles to fit the climate. Eg, the dominant US culture doesn't appreciate or tolerate siestas, even if it's locally more appropriate.
Oh, and this isn't unique to the South. It's cheaper to build a frame house in Arizona, which requires A/C to be livable, than to build an house (like an adobe house) with thick walls that moderate the temperature fluctuations.
Nor is it just A/C. Earthship designs, for example, show what is possible ... for people who are willing to put more work into daily maintenance. Which is part of the lifestyle change that's hard to do.
One thing to note about the A/C issue is that, as global warming progresses, passive cooling will become strictly necessary for survival - most parts of the South will start reaching higher and higher wet bulb temperatures.
No he didn't, the rocks are for asynchronous heating/air conditioning, all you need to get the energy back is a water pump or air blower and tubes.
Your reply is unnecessarily dismissive and snarky. All of those ideas are easy to do projects for individuals.
The only thing you need to implement on a global/national/regional scales is a spot market for electricity accessible for everyone. Then you can lean back and watch people implement all those simple ideas and many more.
All in all, your reply is unnecessarily dismissive and snarky. Those ideas are not "brilliant ideas" (btw you should learn about correct quoting). Of course those won't solve the problem all at once, but they will have a huge impact.
Try not to get suckered into the notion that all ideas are cheap. Bad ideas are cheap and come from a place of either arrogance or ignorance. Great ideas are not cheap, as they typically come from folks who expended the required effort to become a subject matter expert, which gives them foundational knowledge and a better view of the whole picture -- both at a high and granular level.
That said, the parent comment's ideas are bad and ignorant, for the reasons you mentioned and more.
> That said, the parent comment's ideas are bad and ignorant, for the reasons you mentioned and more.
The parents comments are neither bad nor ignorant. They can be summarized as demand management.
Utilities hate demand management. If they run an efficient market with incentives to shift demand, profits drop. Their profits are based on cost, increasing costs is how they improve their margins. Same as healthcare, band-aids cost $1400 at a hospital. When profits are capped by regulation, this is the workaround.
Don't get suckered into fossil fuel narrative. All the narrative against any kind of progress comes from industry that benefits from status quo and regurgitated by media.
I never purported that fossil fuels are a good thing. In fact, I never mentioned them at all and was only discussing the concept of "ideas being cheap." Honestly, it's rather troll-ish and shameful that you've concocted this arrogant rant against an imaginary argument that nobody was making.
You also just bolstered my point about the OC's ideas being bad, because you admitted that the utility providers aren't motivated to do such a thing, which was the entire foundation of his argument -- that some imaginarily ethical regulatory organization is going to force utilities to be equally ethical, efficient and technologically progressive.
And just to be perfectly clear, using a pile of heated rocks as primary energy storage is beyond ridiculous and entirely ignorant of thermodynamics and physics in general.
You're being unnecessarily confrontational. You're also incorrect: there are already utility providers that have started pricing based on load (my provider bases rates on season, day of the week, and time of day, updated annually, so a sort of aggregate estimate that I suspect will become finer grained in the coming years), and thermal energy storage via mass is a very common technique: https://en.wikipedia.org/wiki/Thermal_energy_storage
How exactly am I being unnecessarily confrontational? The OC constructed an entire argument based around something I never said. That is called gaslighting and is the very definition of confrontational, and I have every right to defend myself from it. For you to suggest that I should just accept being gaslit, is both absurd and its own form of gaslighting.
Also, you just made the exact opposite point of the OC in regards to rates, and then provided a link about thermal energy storage that proves the only point I made, which is its inefficiency[1] at small scale -- and at large scale it is not a pile of rocks inside every home.
Again, just because people use the technique, doesn't make it the best or even most appropriate method. It is incredibly inefficient and no technology can make it more efficient, because it is limited by the laws of physics -- which you keep insisting don't matter for some reason.
And again, you're making a sweeping generalization about regulatory organizations that isn't even remotely true, and you have nothing to base it on. In the US alone, the majority of states have systems that combine both regulated and unregulated rates, and even in the states where the regulators decide on the rate, a utility can request rate increases at any time.
Your entire premise is based around some mystical altruism that doesn't actually exist in government or business.
Please elaborate how heating a rock, putting it in an insulated box, and taking it out of that box later to release it's heat to the air is "incredibly inefficient" compared to heating the air directly.
Because it takes 3-5x as much energy to heat rock than water, and at least twice as much as many other common materials. Sorry to say, even air is more efficient depending on the scale of time you're trying to solve for, though its ability to retain that heat is directly limited by the properties of the insulated box -- like a house, for example.
You're going to be tempted to reference the last link as evidence in your favor, but it's very much the opposite. It's saying the advantage concrete has is its ability to be heated to higher temperatures than water. Except it doesn't get to break the laws of physics and still requires 3-5x as much energy input, which is why it's really only practical for large scale operations that can safely heat the concrete to extreme temperatures, using massive amounts of electricity that would otherwise be wasted due to low grid demand. They are still losing at least 75% efficiency in that process, but it's slightly better than losing 100%, as long as you pretend there aren't any environmental impacts of producing all that extra concrete.
You'll notice the first installation referenced in this section actually uses 1,000 cubic feet of additional reinforced concrete and an entire home's worth of additional electricity to supply a single home with 50% of its heating and hot water. That's a second foundation's worth of concrete, for perspective.
And moreover, as we've already established, this concept isn't new at all. If it were legitimately more efficient and more practical than alternatives, every home would already be using its foundation as heat storage. But they don't, because it's not.
To quote, your comment's ideas are bad and ignorant. Not because they are incorrect, but because you blindly insist on them. The reasoning is valid merely for a rock/concrete oven or a vacation house.
I suggest you read up on laws of conservation. If you want to be less than 100% efficient, you have to lose energy somehow, somewhere.
I don't know where you're getting efficiency numbers from, but quoting from your reference, storage in Sorø will double as electricity storage while beating your numbers on electricity alone.
"A similar system is scheduled for Sorø, Denmark, with 41–58% of the stored 18 MWh heat returned for the town's district heating, and 30–41% returned as electricity."
BTW, when you switch rocks for concrete, of course it's expensive and makes no sense - people don't add tons of concrete for thermal storage. Though they do use it, if it's there, and add rocks, brick walls, water tanks, phase change materials etc, if they want more.
You are conflating physically and politically hard problems. It's hard to beat physics, but we absolutely should be talking about, considering and demanding practical yet politically hard solutions. All we have to do is ask, and the alternative is to quietly sink into an abyss.
> And you ignore the fact that if you use car batteries as storage for the grid, that detracts from their use to, you know, run cars.
well, actually car are parked and not used most of the time, even more during nights when there is no solar energy. And TBH this is my mid-term plan: solar panels to charge it by day and use its battery by night for lights and electric appliances (moving to an electric cold/heat pump for heating it's out of my budget currently, I'm on natural gas)
Disclaimer: Founder of Electric Foundation (accelerate EV adoption), Conduit Foundation (require all new construction to be EV ready)
> And you ignore the fact that if you use car batteries as storage for the grid, that detracts from their use to, you know, run cars.
Most people drive about 20 - 40 minutes per day. In large cities, it is 2+ hours. The remaining 22 hours, EV is an energy sponge. Take the current peak load, produce more renewables than the peak, turn renewables to 11, absorb all the excess free energy. EV is primarily an energy storage device, some people take trips on them once in a while. None of this energy is wasted. There is no need to think of a round trip for this scenario. All energy for transportation can be free and clean, we are capturing excess production. Utilities are curtailing renewable production, this is a shame, we have built solar/wind farms, but not using free energy! This is a huge barrier for new renewables, producers have to consider growing curtailment.
> All the books and studies talk about load shaping, contrary to your "astonishment" that no-one is considering this "brilliant idea". The problems with load shaping are many.
Utilities are a monopoly, guaranteed a cost + profit formula. Utilities increase their costs to increase the profit. We see the same formula play out in health care, hospitals charge $1,400 for a band-aid. Energy can be a lot cheaper, and zero. It is entirely possible for Utilities to pay us for using our electric cars storage, they provide the best grid stabilization and smooth out demand and supply curve, flattening the peak rates. Instead of paying 10 - 20x for peaker gas plants, why can’t Americans be paid? There is a nexus of Utilities (generators, producers, distributors) and jacking up capital costs.
> All the books and studies talk about load shaping, contrary to your "astonishment" that no-one is considering this "brilliant idea".
Because these are produced by the utilities. Economists and scientists are funded by the industry to write their view. This happened and continues to happen. [1]
Lead is a gift of God. [2], this view was supported by scientists, surgeon general, AMA, public health and nearly all Govt bodies. Industry sets the rules for all of us so they can continue to extract profits for as long as possible. With this rule, we are all poisoned by lead for ~100 years. Lead poisoning is permanent! "lead does not break down over time. It does not vaporize, and it never disappears. modern man’s lead exposure is 300 to 500 times" [4]. We not only have polluted ourselves, but made a permanent toxic change for all of humanity. For what? To make the richest people a little bit richer?
Koheo's rule (put in place by the industry) was used and continues to be used for thousands of other toxins.
"Using the Kehoe Rule, Ethyl Corporation was a winner in either situation: if its product was actually safe, Ethyl would be seen as a responsible party. If, however, its product was unsafe, it would take decades to demonstrate that with certainty. The process of getting to certainty could be prolonged by challenging the methods and results and calling for more data, and while it was going on the product would continue to generate profits. Kitman indicates that the strategy taken by the lead industry, referring to use of the Kehoe Rule, similarly "provided a model for the asbestos, tobacco, pesticide and nuclear power industries, and other(s)... for evading clear evidence that their products are harmful by hiding behind the mantle of scientific uncertainty."[4] Kettering Laboratories under Kehoe's leadership also certified the safety of the fluorinated refrigerant, Freon, "another environmentally insensitive GM patent that would earn hundreds of millions before it was outlawed."" [3]
Innocent until proven guilty is for people. Should we use the same rule for stuff that harms us? How can we prove this harm when all the studies on harm are done only by the insiders?
The internet that we see today, all the things that are happening in the tech space directly result from the breaking up of AT&T monopoly. We went from circuit switched to packet switched networks, built the underlying networks to throw packets at each other."AT&T, a powerful gatekeeper, controlled innovation by controlling access to the resources needed to innovate – the wires – the physical layer of the telephone network. AT&T's view of Paul Baran's packet-switching design was: ‘It can't possibly work, and if it did, damned if we are going to allow the creation of a competitor to ourselves.’ [5]
The current configuration of the grid is a creation of this utility nexus. We must break this monopoly. If we can figure out how to sling IP packets at each other, surely we can imagine a reconfiguration of the grid that will let us throw electrons at each other. This will result in upto a thousand dollars/month saved for all of us (residential use), as well as making all the energy clean and renewable. Forever.
[4] https://www.typeinvestigations.org/investigation/2000/03/02/...
"Lead is poison, a potent neurotoxin whose sickening and deadly effects have been known for nearly 3,000 years and written about by historical figures from the Greek poet and physician Nikander and the Roman architect Vitruvius to Benjamin Franklin. Odorless, colorless and tasteless, lead can be detected only through chemical analysis. Unlike such carcinogens and killers as pesticides, most chemicals, waste oils and even radioactive materials, lead does not break down over time. It does not vaporize, and it never disappears.
For this reason, most of the estimated 7 million tons of lead burned in gasoline in the United States in the twentieth century remains–in the soil, air and water and in the bodies of living organisms. Worldwide, it is estimated that modern man’s lead exposure is 300 to 500 times greater than background or natural levels. Indeed, a 1983 report by Britain’s Royal Commission on Environmental Pollution concluded that lead was dispersed so widely by man in the twentieth century that “it is doubtful whether any part of the earth’s surface or any form of life remains uncontaminated by anthropogenic [man-made] lead.”
This doesn't really work in a lot of places in the world, because the base things are already too expensive. Most of the world does not have HVAC at home. They don't generate heat with electricity either. Car battery chargers only matter if you own an electric car, own a house and have a charger at home. None of this is relevant to most people in the world. It might be in a couple of decades, but not yet. And this includes France.
Smart appliances are a good idea in principle but rolling them out will take a long time. Water heaters last 10+ years. I don't think there are even any widely available on the market today which will automatically increase the temperature at mid day in anticipation of an electricity shortage later. And it's a safety hazard in homes with small children; hot water temperature should never be hot enough to cause burns when someone turns on the faucet.
Most homes don't have enough free space for a big pile of rocks to increase thermal mass. My home has pretty good insulation but on hot days we're going to be miserable without AC in the evening regardless of how much we chilled the house down earlier.
In France, every electric meter have been (or is going to be) replaced with a new one named Linky.
Linky is an electric meter connected to the grid through PLC but it embeds the required hardware to eventually drive appliances consumption.
It provides a dry contact which can be open or closed remotely via the grid’s PLC. So it can be open or closed even without internet.
You can imagine to use this contact to drive a power line dedicated to your water boiler, electric car …
IIRC, atm, the only provided possibility is to open/close the contact via a web API / a smartphone app. But in the future, it may become controllable by the electricity provider to be automatically opened / closed based on the grid’s state (and the electricity price)
That's great! While probably hard to watch anywhere outside of Germany, there is a mini TV series about what will happen when we all got our smart electric meters:
And before anyone replies that it won't come that far, please consider three things:
- We are using an AC power network, not a DC one.
- The power grid is the backbone of modern society.
- Try to find one big technology deployment which was deemed "safe" and actually kept that promise. Because I can easily find countless counter examples reaching from the Titanic to your latest game console.
The dry contact I'm talking about is totally opt-in. It's a physical contact that is not used by default. You can, if you want, wire it to a power line on which you can plug a subset of your appliances.
So the surface attack of this feature is that an hacker could stop you water boiler to heat or your car to charge, but you'd just have to plug them to the rest of your (still working) network.
And yes, the electricity provider could probably switch off your provisioning remotely. But that's not a novelty. That was always possible. Now it can be done safely.
And I'd like to add that the Linky is NOT connected to the internet. It's connected to the electricity provider network so you need to control the electricity provider in order to hack the meter. But at this point, if you gain control of the network, there is no interest in hacking the meters.
> So it can be open or closed even without internet.
A binary solution is far less efficient than one where the consumer decides if he's willing to pay the spot price or not. Especially if that is controlled from afar.
Shaping demand with prices is how free markets work. Shaping demand via some remote bureaucrat's decision to randomly cut people off is socialism.
> Any it's a safety hazard in homes with small children; hot water temperature should never be hot enough to cause burns when someone turns on the faucet.
That’s a matter of forced mixing. The temp coming out of the hot water heater itself should have very little to do with the faucet temp in 2021. (Yes I realize it still does)
The device is called a tempering valve. It's already necessary if you want a child-safe temperature in the bathroom, because such a temperature is below the leigonella-inhibiting temperature of the storage.
> I don't think there are even any widely available on the market today which will automatically increase the temperature at mid day in anticipation of an electricity shortage later.
Why should there be? Electric rates are fixed 24/7. All the power company has to do is provide an API to get the spot price, and start varying the electric rates according to supply. The market will adapt.
> Most homes don't have enough free space for a big pile of rocks to increase thermal mass.
Criminy. Do I have to design it, too? Most homes have a basement or a crawl space.
Walter, the things you're saying are patently untrue. Many, many countries and municipalities do not have fixed pricing, so you're looking at this from inside a personal bubble, which does not reflect reality for the rest of the world. So with that in mind, what you're actually proposing is a solution that works for some homes, in some municipalities, under very specific circumstances.
I can't imagine anyone wanting to start a business strictly based around a last-mile solution, when other solutions already exist and are substantially more efficient and scalable.
You're also assuming that the regulatory bodies for each municipality inherently want things to be efficient and customer-friendly, but that's just not how it works. In the US alone, all you need is to look at the disaster in Texas this past winter, where prices jumped to 180x their usual rates -- and for brazenly nefarious reasons.
> Walter, the things you're saying are patently untrue.
Want me to show you my electric bill? Fixed rate, 24/7, in every place I've lived, for my entire long life. California, land of the rolling blackouts because they can't match demand with supply, also has fixed electric rates.
> is a solution that works for some homes, in some municipalities, under very specific circumstances.
Oh come on.
> I can't imagine anyone wanting to start a business strictly based around a last-mile solution, when other solutions already exist and are substantially more efficient and scalable.
Look at the endless variety of thermostat innovation for your HVAC system. Even internet connected ones. Why would you suggest that simply automatically adjusting the thermostat based on spot prices for electricity is inefficient and unscalable?
> You're also assuming that the regulatory bodies for each municipality inherently want things to be efficient and customer-friendly
I infer no such thing. I suggested making changes.
> where prices jumped to 180x their usual rates
And I bet none of those customers had thermostats connected to the spot price of the electricity.
Do you know that the pump price of gas varies every day? That's demand shaping. And it works.
Give me a break, Walter. I explain that you're viewing this from within a bubble, and your response is to insist that you're not in a bubble because you, personally, haven't lived somewhere without fixed rates? That's the definition of a bubble argument and self-centeredness.
If you really think your ideas are unique and revolutionary and "correct," then I recommend going down to your local utility and pitching them heated rocks, instead of trying to convince the internet that you're right about everything -- see how long it takes for them to stop laughing.
As an aside, my father invented, developed and sold a heated rocks system over 40 years ago. It definitely worked, but the concept itself proved to be too inefficient, impractical and non-scalable, and because of that it never got adopted beyond a few off-the-grid folks. So, when I say that your ideas would only work in very specific circumstances, that's based on actual historical information, not some imagined universe where the entire world is exactly the same as you, personally, have experienced.
> you, personally, haven't lived somewhere without fixed rates? That's the definition of a bubble argument and self-centeredness.
So, the 5 states and 2 foreign countries I've lived in are a self-centered bubble? I'll turn that around. Where in the US are variable, minute by minute electricity pricing which can be remotely queried?
> see how long it takes for them to stop laughing
First they ignore you, then they laugh, then they race to implement it. What I see in this thread is "electricity rates are fixed 24/7, that's the way they've always been, anything else is inconceivable".
Frankly, why should the utility care? They'd probably profit quite a bit from massive government money to develop grid storage batteries.
It is typical for solar heated homes to use rocks/concrete for heat storage. Traditional adobe homes with thick earthen walls also are very, very good at being a heat sink and source, making the home comfortable. As mentioned elsewhere, I have a Swedish masonry fireplace which uses masonry to store the heat and slowly release it. It's a simple heated rock system. The Swedes have used that design for centuries.
As for your father's invention, I have no idea what went wrong with it. Perhaps a couple manufacturing engineers having a look could improve it quite a bit. After all, rarely does the first iteration of a concept be very practical.
You're proposing nothing but hypotheticals based on what a utility SHOULD care about as opposed to what they ACTUALLY do. And it's an exhausting amount of mental gymnastics.
As for my father's invention, the reason it didn't catch on was for the same reason that piles of rocks don't actually scale -- it's incredibly inefficient, as is every other rock-based thermal storage. Just because it's a functional method of accomplishing a task, doesn't mean it's the best method, and what you've repeatedly asserted is that YOUR idea should be the best method simply because you say so.
Same as Macron's: spending time and effort on reliable generation (i.e. nuclear) instead of wasting it on feel-good drop-in-a-bucket non-solutions. Every single one of those houses can be cooled or heated up if you have energy available on request, no need for massive piles of rocks here and there
It also means more thermal losses and huge thermal masses required to make any difference.
Walter, you are making up science in your head that does not actually exist. I would highly encourage you to do some actual research before you continue to make these incredibly uninformed comments.
> Because it takes 3-5x as much energy to heat rock than water
And 100% of that energy gets recovered as it slowly returns to ambient temperature.
You're confusing heat with temperature.
> you are making up science in your head that does not actually exist
You should be careful about making such statements. You're quite wrong. The heat going into the rock will be 100% returned. All of it. Where do you imagine it will go?
No, Walter, you're confusing energy with temperature. If it takes 1 kWh of electricity to increase the temperature of water by 1 unit (thereby releasing 1 unit of heat to the atmosphere), it takes 3-5 kWh of electricity to increase the temperature of a rock by 1 unit. That's called inefficiency.
I'm done trying to explain 6th grade Earth science to you. You're either trolling or extremely unwilling to accept reality, so unless you have actual evidence for any of your claims, please stop pretending that you're some super genius who knows better than every scientist and engineer on the planet.
The energy comes back out of the rocks in the form of heat. 100% of it. No losses. Energy in equals energy out. If you heat the rock by 1 degree, in cooling off 1 degree it will release 100% of the heat absorbed.
> you're some super genius who knows better than every scientist and engineer on the planet
I suggest you ask an actual thermodynamicist, not a 6th grader. I don't need to present evidence that conservation of energy applies. After all, it's the law.
This is getting beyond ridiculous, Walter, and you're making things up again. At no point did I or anyone else on the planet ever suggest that heating a rock by 1 degree will release less than 1 degree of heat.
As I've explained multiple times now, it's a matter of where the heat originally came from, and it requires 3-5x MORE ENERGY to impart the THE SAME AMOUNT OF HEAT to a rock as it does water. That's the entire point, and is the portion of thermodynamics that you keep pretending doesn't exist. I'm not sure how many more times or ways I can explain this to you, because you clearly don't want to accept that the original heat input doesn't magically manifest itself.
I've provided you with evidence for all of this, but you're still making the same baseless argument. Your ignorance of the subject is exhausting to engage with, so if that was your intent, I guess you win today's Troll Award. But you're still completely wrong about the science, you're unwilling to provide any evidence to back up your claims (because the evidence doesn't exist), you have no basis for your argument at all, and you should be ashamed of yourself for insisting otherwise in such an aggressively arrogant manner.
> At no point did I or anyone else on the planet ever suggest that heating a rock by 1 degree will release less than 1 degree of heat.
Yet you said it was only 20% efficient. Where did the 80% of the energy go?
> it requires 3-5x MORE ENERGY to impart the THE SAME AMOUNT OF HEAT to a rock as it does water
No, it doesn't. It's the same. Unless you've confused heat with temperature. Or you didn't try to heat the rock in an enclosed, insulated box, and the rocks were radiating the heat away almost as fast as it was applied.
"Heat is a form of energy that can be transferred from one object to another or even created at the expense of the loss of other forms of energy."
You finally provided some "evidence" and it literally says the opposite of what you're suggesting. I would highly encourage you to keep reading the subsequent pages on that site, because it goes on to explain the reasons why you're wrong.
> No, it doesn't. It's the same.
This statement is the entire premise of your argument, but is directly refuted by the source you provided, and is so ridiculously absurd that I can't take you seriously anymore. You have to be trolling.
Walter, I've already provided you with a mountain of evidence. You pasted a single sentence stating that heat can be transferred between objects, which nobody has ever refuted, and does not factor in any of the actual physics involved with that transfer -- and then you asked me to paste an entire article as a counterpoint.
Your gaslighting continues, and I'm beyond tired of it.
Brian, buddy, as just an outsider reading this thread I want let you know that Walter is right and you are coming across as rather confused. Also, your aggressive stance isn’t helping.
Walter is right about what, exactly? That heat can be transferred between objects? That heat can be released from objects? Nobody ever refuted those, and those are the only points he has made so far in defense of rocks being a be-all end-all solution which, again, doesn't factor in any of the actual physics involved which make it inefficient.
If you need evidence of that, feel free to read any of the provided materials, especially the concrete heat storage systems that have already been built which, unsurprisingly, use 2x as much electricity to store 50% as much heat.
So, unless you have actual information to provide, you saying I'm wrong doesn't add anything to the conversation.
If it takes X amount of energy to heat a material by Z degrees, then presumably the material radiates exactly X amount of energy back out when it cools down by the same Z degrees, no?
What does it matter that Y kg of rocks stores that energy at a lower temperature than Y kg of water? Or, conversely, that if you insist on having your energy-storage temperature set at some specific Z' degrees, you can store that amount of heat energy in much fewer kg of rocks than of water?
You're mixing up temperature and energy. They're not the same thing.
> Criminy. Do I have to design it, too? Most homes have a basement or a crawl space.
In Europe at least, the vast majority of people live in high-rise blocks, which barely have adequate parking space, never mind any room for electricity storage. None of your solutions are even close to practical from this point of view alone.
Not to mention, relying on the market to be rational really can't be the solution to keeping the grid functional. Blackouts are massively disruptive and potentially life threatening.
I don't, and most don't either: there is no room. We have hot pipes through which hot water is pumped. At best, the high-rise itself has a hot water heater, but even that probably only holds a few hours worth of water. Serious storage is only there at the neighborhood level.
In Arizona, everything was slab-on-grade because the ground was very, very dry. That's not so in most other areas.
The crawl space keeps the wood off the ground where it wicks up moisture and quickly rots. Cement wicks up moisture, too. Try a slab in Seattle, for instance, and your house will soon be uninhabitable from mildew.
> 30 percent of new single-family homes started in 2013 have a full or partial basement, 54 percent are built on slabs, and 15 percent have a crawl space.
> I don't think there are even any widely available on the market today which will automatically increase the temperature at mid day in anticipation of an electricity shortage later.
Our house built 7 years ago has an Enefarm fuel cell/hot water heater. Every house in our neighborhood and every house I’ve seen by the same builder has one. It approaches things a little bit differently but to the same effect. It learns your energy use patterns and turns on the fuel cell (using LP gas) when you usually use electricity, generating hot water as a side effect. The future is already here, it’s just not evenly distributed yet.
> it's a safety hazard in homes with small children; hot water temperature should never be hot enough to cause burns when someone turns on the faucet.
Internally it stores water at 65 degrees C but mixes it with cold water to to supply all water to the house at a certain temp. We have ours set to 40C but you can change it on a control panel. Of course, there are mixing taps at the sinks/showers. It’s very common for shower temp controls here to have a extra stop at 40C that requires pressing a button to exceed.
> Most homes don't have enough free space for a big pile of rocks to increase thermal mass
I don’t know about cooling but the ones that take advantage of cheap electricity at night to store up heat and release slowly over the day are not massive.
> I am utterly astonished that this is never, ever discussed when talking about solutions to fluctuating supply. Having fixed electricity rates 24/7 is simply madness in today's electricity generation situation.
In many areas wholesale markets work on a spot price basis (although players in the market can of course hedge against low/high prices), but consumers have been very reluctant to go with spot price contracts.
This will probably not be helped by the experience of those consumers in Texas who got $10000 electricity bills during last winter's storm, as the prices skyrocketed.
Sure, I agree with that. I guess people don't want to be in a position of having to choose between freezing to death and going bankrupt. So they won't go with the spot-price following contract, even though in some sense it would be better for the grid as a whole.
I suppose this could be handled with some kind of roof price (with the lost money being inserted as some kind of fixed surcharge on the bill or something like that). That would allow reaping most of the benefits of spot pricing without risking bankruptcy during a crisis.
The alternative to demand shaping is the electricity just gets turned off. Which is also what happened in Texas.
There's a name for it: "rolling blackouts". Texas had them, they're also popular in California.
Another name for it is "shortages". Shortages happen when prices are fixed. Having fixed prices does not at all mean there's enough for everyone. Someone's gonna do without.
Shorages also happen when you don't have enough production capability or transportation capibility. See most of what is happening durring the pandemic. I can assure you the price of containers and wood have not been fixed.
Of the two states you mentioned, California is also faceing a housing shortage. I would hazard that the same factors that are causing that shortage are in play for their power problems as well.
Some car batteries may be available but I know for a fact that stock of some ran out. We could not get them from the manufacturer.
Same as ECM for cars. You think that Ford, GM or Toyota would not pay a bit extra to be able to sell cars?
Wood saw a huge price increase but also ran out.
Right now try to source tires. Distributors don't have them, you might be able to find 1 or 2 if you are lucky but you could offer double or triple and you still couldn't buy in volume. Material is not available.
You could buy them from someone who has them. There's a price at which anyone will sell. The problem then becomes the price you'd have to charge for the cars is too much, but someone who is willing to pay that price could still buy them.
Which is why new car prices are up substantially.
If prices were set by law, this couldn't happen (legally). So then the shortages are real.
I manufacture equipment, I can't use used batteries, I need new. If something is not available in the quantities I need, it is not available. Food is a good example of this, in a famine there is not enough food. Money can not buy you extra because it does not exist.
Or another example:
So if I am willing to pay anything, I can get the Mona Lisa? and if you are willing to pay anything, you can get the Mona Lisa as well? There is only one.
But to bring this back to the original topic of the thread, since we have determined that money is no object, why not spend that money to build nuclear power plants.
My water heater is not a storage device for electricy. It lacks the means to recover energy from it, and I want hot water in the morning, every morning, not at random times during the year when there is a surplus of power.
Also, in any cold climate, 'surplus of energy' is generally associated with the presence of sunlight, i.e. at times when heating the house is typically not a great priority. You want that heating on when it is coldest, which typically coincides with the lowest renewable energy production as well.
Charging and decharging your car sounds great, but it means your battery is deteriorating while you aren't even driving.
> My water heater is not a storage device for electricy.
Criminy. Of course it isn't. It's a storage device for HOT WATER.
I have an experiment you can try. Unplug your hot water heater. See how long the hot water lasts. (For me, it remains hot enough to shower for TWO DAYS.) That suggests, to ignorant me, that one does not need to heat the water in it at a moment's notice, but it can be deferred to the cheaper times of the day.
Furthermore, water doesn't have to be heated to a precise temperature. The temp of your shower is controlled by mixing it with cold water. Hence, one can heat the water to a much higher temp when electricity is cheap, further extending the "battery" effect of storing hot water.
If you know ahead of time that you are going to use it like this, you can use a purpose built Thermal Store. It's a huge insulated water tank that you heat up, and then you extract heat from it by running mains water through a heat exchanger with the tank water.
Typically used by people with wind, solar, or burned fuel energy supplies to smooth out energy consumption and soak up extra energy when there is too much. Also by people with variable electricity pricing to soak up free excess energy from the grid at night and heat their home for free all day.
Your water heater quite probably is an electrical storage device, it's been a fairly standard tech for decades in many countries, often using cheap coal or nuclear power at night since they aren't economic to ramp down.
I'd be very surprised if France didn't do things like this. edit: googled it:
I'm quite sure my water heater does not store electricity. It stores hot water, and it completely lacks the ability to turn hot water back into electricity. At best I can use electricity at surplus times to heat water more cheaply, but that doesn't make it 'an electrical storage device'. I cannot attach a light bulb to it, for example, so you cannot use it during dark, quiet days to compensate for the lack of renewable power.
Probably your first line is what caused the confusion.
>The simplest energy storage solution is your hot water heater. Turning on everyone's hot water heater when there is surplus electricity, and turning them off when there's a deficit, is a very low cost solution.
People want a storage solution, not a surplus use solution. Using peak sunlight or wind to heat water isn't going to be useful for a factory or server farm. The only thing that sort of load shifting helps is to diminish peak load.
Yeah, it is probably a great idea to charge your electric car during the day at work as opposed to at night. Maybe a good idea for hot water too, until you have company or teenagers who manage to use up your water in the afternoon.
The pile of rocks to store heat sounds like a nonstarter to me, unless you plan to retrofit a bunch of houses and hope that the heat stored isn't depleted faster for any reason. Otherwise broken pipes at best and deaths at the worst. Not sure how much space you would need for something like that but seems like a problem for small apartments, either the heat leakage would overheat the place or you wouldn't store enough to keep warm.
I said it was a next step. Besides, the government building code constantly adds new requirements for energy efficiency. That's why we have double pane windows today. It was mandated for new construction.
> Otherwise broken pipes at best and deaths at the worst
Good points.
Denmark has a lot HVAC district heating with storage for load balancing planned in it's energy strategy 2050 (as I remember when I read it few years back).
The only way most people can time-shift charging their electric cars to the daytime is if their parking spot at their job has a charging station. Practically, that means a very large fraction of office building parking spots will need charging stations. That sounds prohibitively expensive. Incentives can only nudge so far before you run into genuine problems of logistics.
Charging stations can be installed and can make money by charging the commuters to charge their cars while they work. If the price differential between day & night is enough, it will be worthwhile for both the parking lot owner and the car owner.
Yes but "you can charge it while you sleep" is a pretty popular selling point of electric cars. You're arguing that we should purposely make electric cars less attractive.
People talk about "demand management" as if it's free. Not much power available, just shut down some factories. But if you're running your factories only half the time, you need to build twice as many factories to make the same stuff. You're making renewables look artificially cheap by externalizing costs to their customers.
> Yes but "you can charge it while you sleep" is a pretty popular selling point of electric cars. You're arguing that we should purposely make electric cars less attractive.
Instead, "you can charge it while you work". Not many people drive more than an hour a day - that's 23 hours where it sits. I see lots of cars parked in residential streets during the day. Paid parking lots catering to commuters can also offer charging services.
Any factory wants to run full-speed 24/7. How are you going to manage their demand without reducing their production?
Same principle applies to most things. If electricity stops being readily available all the time, then you're introducing a new constraint that people have to optimize for. If that means they change their behavior, then they're doing something more expensive than whatever they were doing before, when they optimized without that constraint.
That extra cost generally isn't figured into the optimistic estimates of how cheap renewables are, but it's still a cost that society pays.
Building lots of charging stations at employer parking lots is also a new cost, that doesn't get counted against renewables.
Many factories don't run 24/7. And yet more factories don't run their most energy intensive processes continuously even when they factory is "running".
A few commuters to the little town I live in can charge their electric cars during the day while they are at work.
If every parking space had a 7 kW connection (230 V, 30 A single phase) almost all cars could be fully charged while their owners were at work. In fact even an ordinary 3 kW connection would be enough for most people; even my 2015 Tesla Model S adds more than 12 km per hour at 3 kW.
Charging a car takes way more power than running a parking meter.
All I'm saying is, the costs of these sorts of demand management measures for renewables should not be overlooked in comparisons with the cost of nuclear, which doesn't need them.
> Charging a car takes way more power than running a parking meter.
True, you'll need a heavier wire. And the cost of installing wire far exceeds the cost of the wire. When my house was wired up, the cost of the installation was 40 times the cost of the reels of wire.
Also night is a pretty good time for grid load since wind does decently at night, and power use is very low. (since most offices/factories don't use power at night)
Also if your home has a "NightSaver" meter (just what they're called here in Ireland, but basically a day and night meter), the night rate is often nearly half the day rate, so it makes sense to charge at night.
> The simplest energy storage solution is your hot water heater. Turning on everyone's hot water heater when there is surplus electricity, and turning them off when there's a deficit, is a very low cost solution.
This is available in the UK, using a thing called the Economy 7 tariff on electricity [1]. You have two sets of circuits on this plan. One set is the normal set that provides electricity 24/7, so you get expensive electricity when the rate is high and cheap electricity when the rate is low. The other only provides electricity when the rate is lower, such as at night (the 7 in "Economy 7" refers to 7 hours of cheap electricity at night).
There are water heaters designed specifically to work with this [2]. They have a main heating element that does most of the work, which you connect to a circuit that only provides power when the rate is low. These tanks also have a boost heating element that is on a 24/7 circuit meant to just provide any extra heating you need for hot water use during the day.
They also have tariffs that provide a fixed rate 24/7, which should be cheaper than Economy 7 during the day but more expensive at night, so whether Economy 7 saves you money depends on how much of your electricity use is at night.
>I am utterly astonished that this is never, ever discussed when talking about solutions to fluctuating supply.
I'm not surprised to be honest. On a forum like this, you'll get a bunch of very smart people talking about something they don't know a lot about, but authoritatively. (Just look at the incredibly snarky and dismissive responses you've received)
It's certainly talked about in industry and work is going into implementing it.
I work in the electricity-tech industry but I've given up on trying to talk about things like demand response as I'm always shouted down
HN has also snarkily informed me many times that demand for gasoline is completely inelastic.
Never mind that the pump price of gas changes every day, especially when there's an oil refinery explosion, or glut, or whatever. It's a classic example of demand shaping via price. And it works because demand for gas is elastic.
The only time this did not work was when the government regulated oil prices and which stations got a gas allocation. Older folks like me might remember this - long gas lines in the 1970s. Gas lines that disappeared literally overnight when Reagan repealed the price and allocation controls.
How is a refinery explosion, pipeline shutdown or glut proof that demand is elastic?
All that shows is that supply is elastic and that market price varies. For the most part, demand is inelastic. You require the same amount of fuel to go to work/school and return. Now you could vary your shopping habits, go to a shopping center with several stores as opposed to the stores you like. You could put off a road trip or vacation but it isn't like either of those things are the bulk of gasoline usage.
Refinery and pipeline problems are relatively short-term events. Something like an embargo which caused the oil crisis would definitely change behavior and demand.
When you talk about allowing prices to determine who gets and doesn't get a good that is fine when it is a luxury item like graphics cards. But when you talk about the same thing for a necessity like food, water and electricity then getting priced out of the market means death.
Sorry, but that is obviously untrue. If it was true, gas prices would just go up and stay up.
> But when you talk about the same thing for a necessity like food, water and electricity then getting priced out of the market means death.
Then you'll have to accept that the inevitable shortages also mean death. Anti-gouging laws not only produce shortages, they make for less supply overall being available. (This is because high prices motivate increased supply.)
P.S. For just one example, when gas prices are low, people will drive to the store to pick up a loaf of bread. When they're high, people will combine errands and buy more items on fewer trips to the store.
>Sorry, but that is obviously untrue. If it was true, gas prices would just go up and stay up.
Only if there was a monopoly or collusion, otherwise the competition would cause prices to fall to a point just above break even. Well, more complicated than that, prices would fall to a point where it is profitable enough for the companies involved to keep producing the goods and not switch to making something else.
>Then you'll have to accept that the inevitable shortages also mean death. Anti-gouging laws not only produce shortages, they make for less supply overall being available. (This is because high prices motivate increased supply.)
No, you can also over produce something and pay for the over production. We do that with food. That is why you hear a lot about paying farmers to not farm or dumping excess grain in the ocean as opposed to selling it.
>P.S. For just one example, when gas prices are low, people will drive to the store to pick up a loaf of bread. When they're high, people will combine errands and buy more items on fewer trips to the store.
I literally used that as one of my examples: "Now you could vary your shopping habits, go to a shopping center with several stores as opposed to the stores you like. You could put off a road trip or vacation but it isn't like either of those things are the bulk of gasoline usage."
But again, that is not the bulk of gasoline use. Most people are not going to the store for a loaf of bread, going back the next day for hamburger meat and going a third day for salad. Or even making 2 or three trips in a day. Most people don't like to spend their time in cars driving places.
You highlight the biggest problem: humans simply must change/adjust/whatever you want to call it, if humanity is to survive. The only technological out is fusion power. Without that, humans must learn to do with less (of everything). Everything else is empty rhetoric and time wasted.
Or we could use fission instead of fusion? We already have examples of countries using it successfully: France, Sweden, South Korea, and increasingly China. And the US during the 60s and 70s.
Geographically independent power, no carbon emissions, and no intermittency. It fulfills anything we'd get from fusion, except we have 70 years of experience using it in our power grids.
We don't need fusion. Fusion would be nice but we have more than enough fissile material to use well-understood fission plants for the foreseeable future.
The problem is humanity needs to get it's act together and stop allowing politics, NIMBY and a severe lack of understanding of science from getting in the way of saving itself.
Nuclear proliferation is the least of our problems if we can't grow our food outside anymore and half our cities are underwater.
No that's wrong. There are plenty of ways of achieving carbon neutral energy production. Fusion is one of them, but it's unlikely that fusion will be a particularly cheap source of power.
> A battery consisting of a pile of rocks can't be expensive.
> The idea is to not only adjust supply to the demand, but to shape the demand to the supply.
> I am utterly astonished that this is never, ever discussed when talking about solutions to fluctuating supply. Having fixed electricity rates 24/7 is simply madness in today's electricity generation situation.
It might not be the same everywhere but in France and Belgium at least, it is very common to have two rates: peak and off-peak. A signal is sent by the provider to your electrical meter (basically 220V when off-peak, 0V when peak) that can pilot a switch that turns the hot water heater on only during off-peak hours.
Some electric heaters also work on that principle, they are filled with bricks and heat up during off-peak hours then release the stored heat later, when it is needed. That's your "battery consisting of a pile of rock". However, I have lived with those things and it doesn't work at all because storing heat in anything else than water just doesn't work well. Basically at the end of the day, when you come back from work and need the heat that was stored during the night, it's already gone (and totally wasted as the house was empty). The most modern designs don't work much better. I think these only still exist because the idea seems good enough to convince people to buy them, but it's not actually technically feasible.
Anyway, everything you say is already possible in western Europe, and already done (except for HVAC, but that's mostly because HVAC in private homes isn't very common in the first place). What could be improved is to have more dynamic off-peak hours, but that's not a technical problem, everything would already work as is.
I think the problem with storing energy in western Europe, is that you need most energy for heating in winter, when there is hardly any solar power. So any convenient daily pattern doesn't work. For wind, you can probably heat up during the night assuming there is less other demand for electricity.
However, that doesn't help during period when there is hardly any wind. It is not as if you can stop heating your house for a couple of weeks.
I'm curious have this will play out. On a bright summer day, there is plenty of solar power. So it make sense to do everything during the day. During winter, it is better to distribute the load and move load to the night. That requires quite a bit of signaling to get right.
Whilst the UK did indeed have 5 days with less than 2GW wind (not weeks with 0 like you claim), the situation is not as simple as news outlets and agenda-pushers would have you believe. A bunch of other plants (including nuclear) going offline was a major contributing factor.
So you propose to power all of Germany from the North Sea area? In theory it's possible, the North Sea is big enough. But transport costs maybe become an issue.
Well, if the bricks in your heater aren't insulated, of course they'll release their heat prematurely.
I have a Swedish fireplace. The firebox is very small, and the masonry is rather massive. The idea is for the masonry to soak up the heat, then slowly release it long after the fire dies down. Apparently the Swedes have used this design for centuries. I don't imagine the Swedes are such fools that they wouldn't notice for centuries that it doesn't work (it does!).
People also used to put rocks in the fireplace, then pull them out to put in their beds to warm them at night. This is just a primitive method of doing the same thing.
Where I live the vast majority of heat is produced by natural gas or propane. This includes water boilers, water heaters, clothes dryers, cooking ranges and ovens.
This is a good point, but would that ever actually happen? Or would it just be "free" electricity at first and later the electric boiler owners find out that a gas one would've been cheaper after all.
I would consider purchasing an electric boiler if the average operating cost was significantly lower.
Eventually this will make sense, but it’s not something that will happen in my neck of the woods in the next 20 years.
Here in Flanders (60% of Belgium in terms of population) that is not an option. No more pure natural gas heating allowed in new construction from 2023. Gas/heat pump hybrids can still be installed until 2025, but that's it.
It's more strict for oil based heating. Even replacing an existing system is not allowed anymore from 2022.
> The idea is to not only adjust supply to the demand, but to shape the demand to the supply.
This is completely backwards. Demand is highly price inelastic and inversely correlated with the supply of renewables. People usually eat at night. They heat their homes overnight. None of these things will change based on energy prices.
What you're proposing is a tax on the poor, and no practical benefit to boot.
> The charger for your electric car is another very practical sink for cheap electricity.
I don't have an electric car. I do not know anybody with an electric car. And wouldn't the surplus show up specifically when those cars aren't at the home?
> A battery consisting of a pile of rocks can't be expensive.
No, but the labor cost of hooking up your pile of rocks battery will be impractical for almost everyone.
> The next level is using residential HVAC systems the same way.
Again, I don't know anybody with an HVAC system. Everything here in the UK is based on natural gas and would cost an unbelievable amount of money to replace with electric.
> BTW, everybody in Arizona has A/C. Amazingly, A/C demand peaks when the sun is high in the sky.
Here in California, peak AC demand is late afternoon.
Environmental thermal mass means peak outdoor temperature happens a fair bit after peak insolation. Structures take even more time to heat up and add additional delay. Finally, people arriving home from work means increased AC use, too.
Demand stays fairly high after it gets dark.
(And it's my understanding most other places keep daytime heat later than here).
Sure, there all kinds of ways to move demand around from when it would naturally peak based on peoples' preferences.
This particular one is only mildly effective; precooling can lower later demand somewhat.
My house is very well insulated, but I still cannot coast from 5:30pm to 9:30pm (when windows are sufficient for comfort and demand really starts to slope off) without an excessive amount of prechilling. My structure, insulation, and attic are all preheated by the day's heat and so there is a big warm thermal mass next to my living space.
Also, opening windows overnight increases indoor humidity, which in turn requires more air conditioning the next day.
If it'll save you 10% on your electric bill, would you do it? I would. And reducing peak demand by 10% can really reduce the cost and need for grid battery storage.
Best of all, doing this sort of management of your HVAC system costs you essentially nothing. It's picking money off the ground.
We have had "off peak hot water" for many decades. Multiple different rates for peak and off-peak.
It is not useless but it does have its price in terms of complexity and usability. With off peak at night you tend to run out of hot water during the day at times e.g. if you have visitors.
I've never seen it mentioned in any articles about baseline and peak power needs, and all that talk about grid batteries.
> and it is no panacea.
Nobody said it was. If it would, say, reduce the need for grid batteries by 10%, that would be an enormous savings. All by changing a new thermostat.
I remember in the 70s energy crisis the appearance of programmable thermostats what would automatically lower the temp at night. My proposal just extends that.
My house has a 25 year old gas furnace and it is still in solid condition. Had to get the blower motor replaced but that is about it. Our AC unit did not fare as well so we may be upgrading both next year. But yeah, they can last a lot longer than 10 years.
> Demand is highly price inelastic and inversely correlated with the supply of renewables.
The first is dubious, the second is... highly location dependent.
Peak demand in California matches peak solar output pretty well; before solar was big, supply concerns focused on peak demand hours, in the afternoon; now they are in the evening because solar has made the highest gross demand time the time where there is the least concern for supply.
> No, but the labor cost of hooking up your pile of rocks battery will be impractical for almost everyone.
The labor cost of hooking it up isn't that bad, geothermal heat pumps aren't that costly.
Insulating the pile of rocks battery is probably the hard part.
Can't afford a smart water heater? We're just talking about the thermostat for it. I doubt a mass produced thermostat that could get a price from the internet would cost more than $10. I don't know what your electric bill is, but I'd be cash positive in the first month.
This only applies in areas that already use electric heaters.
Anywhere else poor people cannot afford to replace their gas heater with an electric one. And if they rent they have no choice, it’s up to the landlord. In some locales it is common for the renter to pay for the heat bill. So the landlord has little incentive to install a different heating system. In other locales the average cost of heat is factored in to the price of rent and the incentives are basically the same.
> I doubt a mass produced thermostat that could get a price from the internet would cost more than $10
Total costs will be low if you can also find a perfectly spherical plumber (& electrician (& WiFi/4G-technician)) that charges less than $1 per hour for installation.
In New Zealand the law and insurance requires that only registered electricians can work on household wiring, with paperwork per house to confirm. Surprisingly enough most people are unwilling to do something illegal, that will also void their house insurance.
Perhaps the laws and insurance rules are less strict where you are?
I also think that very few people feel comfortable working on household wiring, and very few people are comfortable with fixing plumbed in appliances.
I will add that the law is good, because houses get sold, and wiring is invisible, and no future owner wants to find out their wiring is bodged up by some clueless software engineer.
There is some truely terrifyingly dangerous wiring done by amateurs.
If we're dealing with rural areas reliable internet isn't always a given. The UK had an interesting solution for this for older electricity meters which encodes data in the BBC Radio 4 LW (198 kHz AM) radio station. Most of the country is covered by a single transmitter because of how efficiently LF waves propagate and it doesn't require an internet connection to work. Sadly I think the rise of smart meters will probably be the death knell for Radio 4 LW too.
I think it's easy to forget how flakey the internet can be outside of major cities in some places. Having lived in places that are fairly off the beaten track I wouldn't want my electricity bill to depend on always having a reliable WiFi connection for example.
I work at a company that does DERMS projects in this space (peak shaving, load balancing, power factor optimization, voltage support, etc, etc).
It's not that no one talks about this stuff, it's just that it's as with all things in the utility space projects take time and a lot of the work being done is still exploratory.
No one I work with seems to think this stuff is a magic bullet either, just part of the solution (of which nuclear is another important part).
I should also note that these DERMS projects are very software reliant and I think all of us here on HN know quite well that reliability can be an issue in the software space...
Trouble is, it's nowhere near enough. Cases you mentioned (charging personal cars, heating/cooling down houses) are relatively small. Let's be generous and say it's 20% of overall energy consumption. For comparison, last summer average energy production of UK's offshore wind stayed under 10% of its capacity for a month. How do you even make a dent in this massive sea of missing energy with those small and temporary reductions?
That has a significant risk, what if you hit the end of your range whilst the deficit is still getting worse? Deficits are not following nice predictable normal curves.
I've lived somewhere with storage heaters. They are horrible, practically indistinguishable from no heating at all. A large enough thermal mass would require a complete rebuild.
> what if you hit the end of your range whilst the deficit is still getting worse?
You, the consumer, can override it. You get to decide between donning a sweater or paying more. Isn't that objectively better than some bureaucrat simply turning off the power to your neighborhood (rolling blackouts)?
I live in an area where hot water heating is common. Hot water heaters have secondary loops through the main oil-fired boiler and these could easily be made electric.
A missing link is indeed a cinder block energy storage pile that could be set to preheat water going into the hot water boiler, or to cycle through water going into heating.
>>"The simplest energy storage solution is your hot water heater. Turning on everyone's hot water heater when there is surplus electricity,"
I already do this manually. I unplug it before taking a shower and plug it again at night. Of course, doing it automatically is the only way is going to be done at scale.
I wonder how recharging the net from a plugged in e-car would affect the lifetime/resale-value of that car, if that concept would be in general use. And how the grid then would develop, regarding overall capacity.
Those sound like cost savers, not the mass storage solution that is needed. I haven't done the math but I bet you're missing about an order of magnitude of storage needed to make intermittent power sources sufficient to power the grid by themselves.
The next level is using residential HVAC systems the same way. Comfortable temperatures are a range, so heating/cooling can push the temps to one end of the range, and when there is less electricity available, they can drift to the other end.
The charger for your electric car is another very practical sink for cheap electricity.
This is accomplished by having a spot price for electricity, and then people buying thermostats that query the spot price and turn HVAC, hot water heater, car battery chargers, etc., on and off.
This can be extended EVEN FURTHER by heating/cooling a pile of rocks to later use to heat/cool the house.
A battery consisting of a pile of rocks can't be expensive.
The idea is to not only adjust supply to the demand, but to shape the demand to the supply.
I am utterly astonished that this is never, ever discussed when talking about solutions to fluctuating supply. Having fixed electricity rates 24/7 is simply madness in today's electricity generation situation.