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The article is just wrong. And only mentions energy used for heating in passing. Heating requires MASSIVE amounts of energy. I should know bc I have a whole ho
by declan_roberts 6mo ago
The article is just wrong. And only mentions energy used for heating in passing. Heating requires MASSIVE amounts of energy.
I should know bc I have a whole house battery and solar system (almost 30 kWh battery and 24kW solar). It keeps the lights on, but not heating. I live in a mild climate.
The reality is that battery/solar requires major quality of life and activity time shifting trade-offs.
- abenga 6mo agoIf you need to heat/cool your home, is that really mild?
- declan_roberts 6mo agoIsn't it all relative? Cooling actually isn't a problem at all with solar. I can run my AC full blast during the summer and still get the batteries fully charged before evening.
- iamjake648 6mo agoDo you have a high efficiency heat pump, or how are you heating?
- barbazoo 6mo agoHeat pump is what I would have expected to be suitable for a setup like that. How big is the house I wonder.
- declan_roberts 6mo agoI imagine my system is probably sufficient to keep an 800 sqft house comfortably warm in a climate where it goes down to the 20s in the winter.
- lstodd 6mo agoFirst question should be: what latitude? Because where I live around 55th this winter we had five straight weeks below -15c / 5f daily average plus enough snowfall that it was infeasible to clean anything but the most major roads. Solar is out of question in these conditions and when thermal pump fails you have to evacuate. When just grid electricity fails you have to either have some sort of stored fuel backup or evacuate. The article is typical handwavy crap which is popular among people living in what amounts to subtropics who can't even imagine how crazy they sound to most everyone else.
- Windchaser 6mo ago> The article is typical handwavy crap which is popular among people living in what amounts to subtropics To be fair, 90% of the population lives within 45 degrees of the equator. If we're talking about global energy solutions for CO2 reduction, we can go a long way just by focusing on what works in these areas of the globe. The article does also point out that hydro/wind are going to be important at higher latitudes in winter, but they also acknowledge that they don't account for seasonal variation in demand. That's the biggest flaw I can find in the analysis. FWIW: I'm down in a mild arid climate at 35N, and yeah, 90% of our winter days are nearly sunny, even when the lows are in the teens. It's a different world for sure.
- coryrc 6mo agoMost space heating is in the Northern parts though, so those are the ones that need to be addressed. There are solutions that are a pareto improvement, but it's a coordination problem and the USA is sufficiently broken and unable to solve those.
- pixl97 6mo ago> so those are the ones that need to be addressed. Make energy so expensive that people have to move away or burn their old house.
- 6mo ago
- cbdumas 6mo agoThe article is about utility scale solar and storage I believe not home installations. It also mentions towards the end that in cold norther climates adding wind to the mix makes sense
- declan_roberts 6mo agoLike I said he grossly understates the energy demand we use in the United States for heating during the winter.
- Tade0 6mo agoI believe a lot of that demand is due to there being no incentive to increase energy efficiency.
- declan_roberts 6mo agoI believe it to be a question of physics and not incentives.
- maxerickson 6mo agoA wall is not a wall is not a wall. A well built home with more insulation will, according to physics, lose less heat in any given scenario. So policies that push for things that improve buildings can reduce energy use. Do you think we have reached peak building efficiency or something?
- pixl97 6mo agoKind of silly to think when we've invented materials like areogel.
- deleted 6mo ago[deleted]
- caseysoftware 6mo agoThere are TONS of incentives to increase energy efficiency. Most local electric and gas companies will do free energy audits. Many will offer rebates if you install tankless water heaters, heat pumps, and insulation. Installers get kickbacks from manufacturers and tax credits if you buy higher efficiency equipment. Lenders will give you 0% loans to fund it all. The Feds and many States offer tax credits for all of the above. I've done every single thing on this list in the last 5 years, some in Texas, some in Indiana.
- j16sdiz 6mo agoThe insulation matters a lot in home heating.
- PyWoody 6mo agoProper windows make a huge difference, too.
- gib444 6mo agoAnd then you need proper ventilation systems once you "fix" insulation
- bluGill 6mo agoThere isn't a lot you can reasonably do to something that is already there. I insulated my attic better, but there wasn't enough space to go as high as I wanted (I guess I could in the middle, but not around the edges). The thin walls are still thin, and not much I can do about it for a reasonable price. Likewise the windows are really bad, but the cost of good windows is large. By the time I insulated this house to modern standards I'm nearly half way to tearing it down and building something new (a complete destroy is a lot cheaper than trying to take something off without destroying the rest) - and a new house would get a lot of other benefits (I want a larger kitchen but there is no place to put it) Which is why a lot of poorly insulated houses still exist - people have mostly done what can be done for a reasonable price, but anything that will make a difference is also very expensive with very long paybacks.
- panstromek 6mo agoAs far as I understood it, it only talks about electricity, so that doesn't seem like a contradiction to me. I think some electrification of heating is expected in 2030, but not that much bigger than it is now.
- Epa095 6mo agoWhat's the actual effect you get out of that? Even half, 12 kW, would be an absolutte beast of heating (for a home), even with 'dumb' convection heating. With heat pumps 2-3 kW should really be enough.
- declan_roberts 6mo agoThere's simply not a lot of sunlight to go around during the winter and the battery capacity isn't large enough. Keep in mind we WFH and homeschool so our house is used 24/7 and I think it's a good approximation for OP's goal.
- mr_toad 6mo ago> the battery capacity isn't large enough This. You have enough generation to keep a mansion toasty, but you don’t have enough storage to last a long winter night.
- fooblaster 6mo agowhere are you? that is a massive amount of solar in any place at a reasonably low latitude. Is your house enormous or are you heating your house with resistive heating?
- mapmap 6mo agoThis is a large pv system for what I assume is a single family home. Do you have resistive in floor heating or an electric boiler feeding radiators? I imagine you could easily run a half dozen mini-splits drawing 500-1000w each, or a centralized heat pump. Happy to help if you can give more details.
- PyWoody 6mo agoI live in a northern climate and I know multiple people who are net zero with solar+basic battery. Proper insulation and good windows go a very long way. For instance, I set my heat to 66F during the day and 60F at night. When I wake up in the morning, the register is usually still above 60F.
- HoldOnAMinute 6mo agoThose brutally cold temperatures are really not compatible with most human beings
- declan_roberts 6mo agoWeird because a significant number of humans beings in the USA immigrated at some point from a country in this climate.
- mtoner23 6mo agoNet zero. But not effectively zero. They sell energy during the day when no one needs it and buy it an night when we all need it. If we all switched to solar and heat pumps there would be blackouts and an energy crisis
- PyWoody 6mo agoWhat? They store the surplus in their batteries during the day and use it at night. I genuinely do not understand why people are so afraid of solar. It's baffling.
- blackcatsec 6mo agoThey've fallen victim to a catastrophically easy scare tactic, unfortunately. "The sun only shines during the day therefore solar is bad!" Dumb, but easy.
- declan_roberts 6mo ago
- Rover222 6mo agoWell obviously lights aren't using up much of that power, you're powering everything else too.
- toasty228 6mo agoPeople still build houses like energy is cheap and abundant. A properly insulated house in any temperate climate require very little heating or cooling. Spend 50k on insulation that will last the life of the building instead of 50k on heating and cooling devices which will need constant maintenance and replacement + fuel and end up costing 10x more over the life of the building. A modern house with modern insulation in a mild climate shouldn't even need a central heating system. You can get by with 500w toaster heaters in each room for the coldest time of the year
- baking 6mo agoProbably because energy is cheap and abundant.
- JKCalhoun 6mo agoAnd never mind ground-source heat pumps [1] (although I know the topic was specifically solar). [1] https://en.wikipedia.org/wiki/Ground_source_heat_pump https://en.wikipedia.org/wiki/Ground_source_heat_pump
- toasty228 6mo agoYou don't even need to go that far, put 100m of tubing 2m underground and plug it in your heat recovery ventilation system, bam free winter freeze protection/pre warming and free summer cooling, all you need is a 30w pumps and you will save hundreds of kw per year
- a_random_name 6mo agouh no... You still need a heat pump. The water coming from that system would be like 50 degrees, far too cold for heating.
- toasty228 6mo agoI think my comment is pretty clear about the use case, this is obviously not water for your floor heating. You shouldn't even have that in a properly insulated house, way too much inertia. There are electric floor heating graphene foils that put out 20w per sqm, they're more than enough, no moving part, no maintenance, no bs, not even 20% of the price of a hydro floor heating, you can even install them yourself
- dyauspitr 6mo agoIs a 30 kWh battery considered massive? My F-150 lighting has a 143 kWh battery.
- declan_roberts 6mo agoYes 30 kWh battery is considered large. It takes up a full 6 slot 2u rack in my garage and cost around $8k. In the context of OP's goals it's larger than what 99% of people in the world will ever have.
- gpm 6mo agoApproximately 1% of people in the world currently have an EV with a more than 30 kWh battery... and we're very early in the adoption curve of EVs and other large batteries.
- declan_roberts 6mo agoOwning an electric vehicle is a lot different than having a house wired with solar panels and a battery and inverter.
- jakewins 6mo agoRespectfully, 30kWh is not much in this context. In 10 years every modern 2-car home will have 200kWh on the driveway just from the EVs; add a 100kWh whole home battery at a price point close to a 10kWh battery today and the calculus changes in most of the world. The cost of materials going into modern batteries easily leaves room for another 10x reduction in price, IMO where this all is heading is obvious. Zero marginal cost will win every day of the week. FWIW we run our cabin on 15kWh battery today year around, though we do run a small wood stove to supplant the heat pump on cold winter days.
- coryrc 6mo agoI bet you didn't even see the tragic farce when writing your solution. Land development requiring ”2-car homes" is the driver of the problem! An apartment only has to heat one or two walls facing the outside instead of 4. That's 50-75% right off the top of your energy usage, with the mean closer to 75%.
- LogicFailsMe 6mo agoThere's nothing farcical about wanting one's own space where there's space to have one's own space. I'm grateful to no longer be sharing walls with a domestic abuse couple on one side and a midnight banshee on the other wall when she got busy. Energy is cheap, people are exhausting.
- coryrc 6mo agoAnd that gets into another coordination problem we're unable to solve. It's a solved problem to build apartments where you can't hear your neighbors, but the builders don't have incentive to spend the money upfront to do so and we add regulations to make it more expensive for them to do so. So people go on thinking "apartments suck" and not the correct "we shouldn't let people build apartments which suck". Also, living in SFH isn't avoiding all problems. I'd rather live in a properly-built apartment than my old house when my neighbor left her dogs outside to bark for the entire work day, every single day, and all the city would do is fine her a hundred bucks every few months. (or if you want to say "rural", that's 1 a small fraction of the population and 2 I like hospitals).
- dv_dt 6mo agoBeyond the other better insulation comments, pairing electric with heat pumps that are SEER 10+ goes a long way to improve heating efficiency. Old resistive heaters are 1:1 on energy to heat, while newer heat pumps operate to much lower temperatures, and give you 1:10 or 1:15 electric:heat energy ratios.
- bluGill 6mo agoMy heat pump is SEER 19, and it can't heat my house below 25F. I think this is mostly due to it not being large enough - it was sized to cool my house on the hot summer days, and more energy needs to move on the cold winter days.
- coryrc 6mo agoSEER, while a useful first-order approximation of efficiency, is for cooling and not heating. HSPF-V is for cold climates. Likely you just don't have a cold-climate heat pump which maintains full capacity down to -10°C (and some a little lower still), even before you get into appropriate maximum capacity.
- coryrc 6mo agoThat's not even close to correct. At the design lowest temperature (if <15°C), the very best get 2 COP, but most are 1.5 or lower. The problem is you have to accommodate the worst case. The average of installed units is closer to 2.0 COP average, unfortunately. Multi-head units really drive down efficiency. A single-head Gree Sapphire can do 4-5 COP on average and that's the best you can get, so still nowhere near your guess.
- orthecreedence 6mo ago> 1:10 or 1:15 electric:heat energy ratios Under what circumstances? I've seen higher-end units that do maybe 1:5 in ideal conditions (heating to 68F when the ambient temp is 55F), but never seen units that do 1:10 or 1:15. This was about 2-3 years ago I did this research. Have things improved that drastically in the last few years?
- FEELmyAGI 6mo ago> I should know bc I have a whole house battery and solar system This is not really a qualification to speak on how the grid works, at all. Actually having panels on your roof doesn't give you unique insight into how solar panels operate - there is extensive data out there, any PV installation can become a data source trivially. > The reality is that battery/solar requires major quality of life and activity time shifting trade-offs. One residence powering itself is not representative of how the grid works, and is not a good way to evaluate any power generation technology whether its PV, coal, nuclear, etc.
- declan_roberts 6mo agoI'm actually trying to accomplish what the author is describing, so I have experience to talk about the difficulty of its implementation (unlike the author himself, who has zero experience with its implementation to speak of).
- amluto 6mo agoDo check that your heater isn’t doing something ridiculous. A while back I helped someone debug a Mitsubishi Electric system on which the installer had set the fan speed control to high instead of auto (it’s an easily accessible setting on the thermostat). I forget exactly how much power was saved, but IIRC it was well over 30kWh/day. I don’t know where all that energy was going. I expected some improvement but not anywhere near that much.
- Faaak 6mo agoHeat pumps help quite a lot, thanks to Carnot's law
- declan_roberts 6mo agoHeat pump efficiency noticeably drops off after 25°F. Which is when you really start to need it!
- DanTheManPR 6mo agoThis is basically correct in the sense that we cannot simply just force everyone in, say, Minnesota to install electric baseboard heating, rooftop solar, and a battery pack, and then expect them to stay warm. There are periods of extended extreme cold and low solar flux where you would simply not be able to warm everyone's house - that's just physics. But there are a lot of extra things you can do as an intermediate steps to dramatically close the gap. The main ones are: 1. Homes can be renovated to improve insulation 2. Cold weather heat pumps can handle most mild winter conditions efficiently 3. Electricity doesn't all have to be locally generated - it can be transmitted from other parts of the country. 4. You can keep using fossil fuel peaker plants, and still have incredible reduced overall emissions
- jacquesm 6mo agoHouse heating does not require massive amounts of energy. What it requires is efficiency. I've seen a house in Canada that was heated with a single candle when not occupied. Triple wall, reflective foil in between the wall layers, vertical movement of air in the walls interrupted every 30 cm or so. Absolutely amazing. And it still had sizeable windows. If your house doesn't leak energy like a sieve you don't need to replace as much either. Between passive solar and some augmentation you can do fine on an extremely modest energy budget. And Canada is not exactly the warmest country on the planet.
- minajevs 6mo ago24kW solar "to keep lights on" is a funny way to underplay it. My house "summer" electricity usage is 60kWh per month, including water pump, DHW, septic and work from home for 2 adults. So 3h of your PV production would power my house for a month! Regarding heating - I live in cold climate. We had average daily temperature of -10c this january, with multiple lows at -25c, and most nights at -15c. The house is 116sqm. Our heatpump COP for that month was above 2, and we used 787kWh total to heat the house, which is not a lot, actually. At 15 cents per kWh it is 118 euros for heating, for the coldest month in a decade! Considering also that we do not pay for electricity since april until october (solar panels). We also paid less than those houses which use natural gas, wood pellets, etc. We also do not need to do anything to keep house warm. Also, during summer months we could "drive for free" in EV due to free solar electricity. All that just to counter your take on "major quality of life and activity time shifting trade-offs".
- ZeroGravitas 6mo agoNote that the article title has "the world" in it, immediately limits his specific claims to 80% of the world nearer the equatorr as most of the people in the world have more need for cooling than heating. He even has a map that covers this and multiple paragraphs of discussion about high latitudes and wind in winter.
- LogicFailsMe 6mo agoMy house in the bay area runs at <1kW per hour most of the time and the sunlight is more than enough to keep it above 65F most of the year. Maybe you need LED lights because when I'm not there, it's ~150W per hour. Of course actual data like this is downvote heresy! Go for it! Also, bite me.
- tzs 6mo agoThat power use seems reasonably believable. I'm in the Puget Sound area where we get less sunlight than you and our winters are colder, and I just made a graph of my daily electricity use for 2025 [1]. My house is all electric. I had 219 days with under 24 kWh use, i.e., drawing an average under 1 kW. I got an EV in mid April that year which I charged with the included level 1 charger until getting a 12 kW EVSE installation in I think May. (2024, the last year with no EV charging, had 240 days under 24 kWh). Almost every day that was over 30 kWh after that was a day when I charged the car which was typically on a Saturday which is also typically when I do laundry which includes about 5 kWh for the clothes dryer. I was puzzled by the large number of days near or above 50 kWh in February. The end of 2025 doesn't look like it is setting up 2026 for that high a usage. I just checked the weather records and it doesn't look like that was a particularly cold time. I just made another graph just showing February 2024, 2025, and 2026, and a third showing January of those 3 years, and both show that in 2026 I'm using quite a lot less power (except for the EV charging) than in the prior years. I've not changed any habits...but in November 2025 I had my house weatherized. They added a lot more insulation under the house (I already had sufficient attic insulation) and did blower tests and sealed everything that was leaking, and it appears this cut energy use by somewhere in the 10-20% range. It seems then early 2025 appears so high because the end of 2025 is showing the effects of weatherizing. [1] https://imgur.com/a/QAnOvm7 https://imgur.com/a/QAnOvm7
- ethagnawl 6mo agoThe article should have explored that aspect further but it's not all or nothing. For example, a geothermal setup could significantly offset the amount of energy required to heat a home.
- FuriouslyAdrift 6mo agoHeating is mostly affected by the roof insulation and really should not be done with electricity alone. It's just not efficient. Cooling, on the other hand, is brutally expensive without living in basically an air tight Styrofoam box (or underground).
- daneel_w 6mo agoGonna go off on a limb and guess that you live in North America where the state of the art in single-family homes is double-pane windows and thin outer walls made of cardboard and pressboard, clad with "luxurious" vinyl siding. I mean no offense to you guys. It is what it is.
- declan_roberts 6mo agoMy home is less than 5 years old and has the highest R-value fiber insulation I could find before moving to spray foam. People just really underestimate how much energy it takes to produce heat, and how little energy a solar system produces in the winter. Double whammy!
- asdff 6mo agoI'm not sure how sustainable it is at scale but I know someone who winters off a woodburning stove. They basically get their wood for free from trees that come down in their yard or people's yards that they know. They use a hydraulic woodsplitter to manage splitting all the wood.
- morphle 6mo agoYou should store your solar energy as heat. You move the heat from outside or underground into your house with a heat pump where the heat storage lasts a week or more. You need very little solar to heat your house this way. So for a mild climate your installer seems to have done you a disservice and probably overcharged you. You can heat an average house with solar for under $14K if properly installed.