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Yeah, the technology connections video on this was fantastic. If one was to cover that land in solar, you’d produce far more than the current energy demands of the US.

Relying on an energy source which requires constant, continuous resource extraction is fucking stupid when we can spend resources up front and get reliable energy (solar + battery) for decades with minimal operating cost & maintenance. And then we’ll have a recycling loop to minimize future resource extraction.

If you want to debate that, spend some time with this video first: https://youtu.be/KtQ9nt2ZeGM

Kinda funny how we invented a carbon neutral fuel system but we are like "lets only use it as a 15% mix" vs trying to design new engines for pure ethanol. You could fuel your car with hooch you made from yard waste.

What does the 1% of land used to grow corn have to do specifically with solar and batteries? Solar doesn't need to be on the 15% arable land at all.

The corn doesn't just produce ethanol, which just utilizes the starch/sugar. The protein, fat, fiber is eaten by livestock in some form like distillers grains.

And governments like to have food security , and having secondary uses for an abundance of food in the good times is more convenient than storing cheese in caves , and in case of an emergency shortage the production is already there without having to rip up solar panels to grow food.

My conclusion is you're conflating issues (solar and ethanol) unnecessarily.

I’d rather people went rooftop solar, and put that land to producing food.

Correct me if I’m wrong but my understanding was that ethanol in gasoline was a result laws enacted due to corn farmers (or their state reps) lobbying for subsidies, not any intrinsic part of gasoline production

Damn I didn't know it was that bad. Ideally you'd grow algae from sewer waste and make fuel from that, but this is the US we're talking about.

People 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

I 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.

24kW 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".

Respectfully, 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.

This 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

> 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.

The 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

Beyond 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.

House 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.

What'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.

The insulation matters a lot in home heating.

Heating 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).

Do you have a high efficiency heat pump, or how are you heating?

As 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.

Do 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.

Note 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.

The 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.

This 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.

Is a 30 kWh battery considered massive? My F-150 lighting has a 143 kWh battery.

Gonna 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.

Heat pumps help quite a lot, thanks to Carnot's law

If you need to heat/cool your home, is that really mild?

where 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?

Well obviously lights aren't using up much of that power, you're powering everything else too.

My 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.

I doubt that issue scales to the national grid at all... national grids tend to dictated in size by more or less market forces not careful pre-planning... and capacity planning for new projects tends to have actual data about energy demand and weather patterns and so on.

I build off-grid electrical campers (Mercedes eSprinter) with extended 600kWh batteries (11 times more battery capacity than the default model) and charge them from solar panels at home. I disagree with your negative mindset, people who ride in my eCamper quickly learn you can go 100% solar and use you camper at home to store all neighborhood solar and even charge other EVs from our eCamper battery. We make our own parallel battery cell dis/charger to extent the LFP battery life to 20000 charges (one a day for 50 years).

Very nice. I have my eyes on Lithium-Titanate cells for my house, I can't wait until they go down in price enough. Weight and energy density are not an issue, but safety is and those cells are very good in that sense.

https://en.wikipedia.org/wiki/Lithium-titanate_battery

> Scale that mindset problem up to a national grid and I imagine the challenge is the same.

Except that we have raw data there? The only question is how fast it grows, but since we're transitioning that's mostly a question of how fast you decommission fossil plants.

there is a youtube video I watched where an RV guy converted as many appliances and gadgets on his vehicle to Direct DC as he could, saved a lot on wastage from DC-AC-DC conversions.

We need mundane home DC solutions.

While I agree with underestimating capacity, the problem only really applies to off grid.

For regular homes, it just means less savings.

At the consumer scale the biggest thing we could do is follow the german model of panels that can be plugged into an outlet and installed in an hour by any homeowner (with the same capacity limits and requirements on the panels electronics to protect the grid/line workers during power outages).

That said I'm pretty sure that grid-scale solar is the future of most solar energy, not home solar. It's just cheaper to do things in bigger batches.

There's been a wave of legislation[1] introduced in the US to legalize so-called "balcony solar," small grid-tied solar systems that plug into a regular household outlet with zero permitting or interconnect requirements. This is already common in Europe, it's mildly complicated by our split-phase system but not much.

The reason for the high burden today is people have developed an inflated sense of how much the kWh they generate is worth. They install massive systems on their roofs to try to "cancel out" their power bill by exporting their entire daily power consumption over the course of a few sunny hours, which (when all their neighbors do the same) ends up being a costly burden for grid operators who then pass the costs on to users without panels. Smaller systems focused on immediate, local consumption rather than export are much better for the grid which is why they have support.

1. https://www.canarymedia.com/articles/solar/balcony-solar-tak...

100% this. If it was DIYable, its an order of magnitude cheaper.

I have leftover panels from an off grid install, and its extremely hard to get an approved permit for a small roof solar array + off the shelf AIO (Ecoflow/Anker)

I emailed you. You can work with us as it is a booming market in Europe and Ukraine (and probably in China too), you could expand our market into the USA. We build charging stations, big batteries (see my other posts in this thread and in my HN profile), Enernet smart grids and entire solar only neighborhoods (houses, solar, batteries, fast internet, water and sewage infrastructure) remotely, all based on 100% solar. From $40K per tiny house.

Or you are somewhere in Africa and have no electricity anyway so you start on something renewable.

I think this sells the German energy mix short - fossil fuel has been on a steady decline in the energy mix for about 2 decades now.

Comparing 2020[^2] to 2025[^1]:

- renewables (solar+wind) went from 181 TWh to 219 TWh

- fossil (coal+gas) stayed constant (177 TWh and 179 TWh)

So I'd say we switched from nuclear (60TWh in 2020) to renewables & imported nuclear - but the long-term trend is towards renewables.

[1]: https://www.ise.fraunhofer.de/en/press-media/press-releases/... [2]: (pdf) https://www.ise.fraunhofer.de/content/dam/ise/en/documents/N...

The fossil fuel lobby can only do so much. Solar has gotten so cheap it's taking over on its own. Companies are doing it for no reason other than the math makes sense. EV batteries are nearing that point too. You can only keep BYD out of the US for so long.

The fossil fuel industry is fighting a rearguard action at this point.

> Germany shifted from nuclear to coal and gas

Sure, but you're attributing this, deliberately or not, to the wrong cause. It wasn't that the fossil fuel industry somehow won - it was range of factors possibly including geopolitics, some existing plants aging, an emotional response to the Fukushima nuclear disaster, and the Green lobby.

Basically, they voted to kill nuclear without a solid plan for an alternative, and coal/gas is the default option for filling the gaps left in the absence of timely and sufficiently rapid investment in other technologies.

I mean yeah, but $100 a barrel makes it difficult to argue.

The article specifically notes the following:

>We can get far without worrying about the last 5-10%. The solutions for the last 5-10% could be fossil fuels in the short-term, long-duration storage as it matures, or easily storeable e-biofuels.

The goal of getting to renewables is to not remove every carbon source but to slow the rate of change so we can adapt. 90% meets that.

Musk was proposing about 1.2TW of solar capacity, the US installed about 250GW since then and is currently installing about 50GW a year and is projected to have 770GW by 2036 in a decades time.

So the US is probably over-delivering compared with many things Elon has proposed delivering himself.

At temperate latitudes, summer/winter is a bigger deal than day/night. To the point where it makes sense to orient fixed panels tilted south and you still get a 2-3x difference in daily capacity between the seasons.

Related is the other comments here that mention air-conditioning is largely a non-issue if you spec for year-round solar. If you are generating 3x as much energy in July compared to January, and January can power your house, then the A/C is basically free.

You can buy a full day's worth of energy storage with an array of LiFePO4 batteries for less than the typical 3% estimate of annual home improvement and maintenance costs you should be budgeting for as a homeowner. The cost problem usually comes from the labor and every solar installation company seemingly being ran by scam artists.

Thats whats driving the buildout in places like spain.

Solar power is in curltailment most days, so to make money solar operators need to add batteries to take free energy and shift it to the ultra expensive parts of the day.

grid-scale batteries are accelerating more rapidly than anyone thought a few years, it’s not really seen as an unsolvable problem anymore

Because solar energy production doesn't just vary by time-of-day, it also varies seasonally. Where I live, winter solar production collapses due to decreased daylight hours and cloud cover. At the same time, energy use skyrockets due to heating demand.

We would need a lot of batteries to be able to charge during the summer and drain during the winter!

Tell me you didnt read the article without telling me.

Yes. It literally says:

> The cost assumptions assume utility-scale solar panels and batteries in large parks. Smaller-scale rooftop solar and home batteries would cost 2-3 times more.

I've installed domestic solar several times. The main cost isn't the panels or the inverters - it's the scaffolding, labour, and wiring improvements in the home. If you have a tall or complicated house, it'll cost more.

The next generation of home batteries will be a game changer. It will do for home energy storage what Lithium-Ion has done for laptops, phones and vehicles and it will be a lot safer too.

If you could install solar at ~150% of the cost of utility scale solar it’d make a ton of sense, but at 300%+ it’s hard to make the math work

The article ignores hydropower. The numbers/prices look a lot better with solar + wind + hydro + battery.

Norway runs almost entirely on hydropower. Sweden has a lot.

Iceland runs on hydropower and geothermal.

And nuclear is already in the 5-10% range in the US, so if we just maintained that level, we could get carbon free.

The American shale gas/fracking boom really distorted a lot of things. The strategic energy situations of the United States, the EU, and China were all pretty similar in the late 20th Century: major dependence on OPEC-controlled oil and gas. Post-fracking, the US strategic energy situation has diverged from the others.

This difference leads indirectly to things like the current "not war" in Iran. (Iran's geography already gives it strong bargaining power via pressure on energy markets. It would have an even stronger hand if the US was not capable of energy independence).

The long term impacts on climate changes are even more negative. It's hard to supplant a cheap, ubiquitous energy source with strong negative externalities when those externalities are subtle, gradual, and strongly denied via propaganda by entrenched interests.

I agree and lets not label something as dangerous or expensive if it can be made to be affordable and safe. "As of 2026, 59 nuclear power plants are operational in mainland China, second globally to the United States, which has 94." "There are over 28 further plants under construction with a total power of 32.3 GW, ranked first for the 18th consecutive year"

https://en.wikipedia.org/wiki/Nuclear_power_in_China

China burns significantly more coal than the USA and Europe combined and has no environmental laws standing in the way of their nuclear power plants.

Imagine a world where people don't care about labeling new things as "regressive" or "anti-environmental"

Apart from the current administration's absolutely hilariously bad governing, the US economy really only cares about profit. The same is going to happen to any country with outsized income inequality.

They're not anti-renewables as a bet, they're anti-renewables strategically. If you like going to war, you can power your warfighting apparatus much easier with a gas tank than a battery. If you want better defense, you don't depend on hostile nations for your energy needs. The US wants to double down on oil because it likes to fight wars and it's paranoid about defense.

This is just incorrect. The politics in the US say one thing but the market is going in the other direction. 2026 additions to the US grid will be almost entirely renewables - 6.3 GW of natural gas / 86 GW total means ~93% of new additions to grid capacity are renewable [1]. A quarter of the electricity in the US is now generated by renewables [2] and growing rapidly. The states with the largest amount of renewable electricity generation are wildly different politically, but all agree that renewables make the most financial sense [3].

[1] https://www.eia.gov/todayinenergy/detail.php?id=67205 [2] https://www.semafor.com/article/03/03/2026/us-renewables-hit... [3] https://www.integrityenergy.com/blog/the-top-10-states-pavin...

There are influential people who make lots of money when the US Govt forces the country to rely on fossil fuels.

Unsure why you're getting downvoted. I know politics is generally frowned upon here but this is absolutely relevant to the conversation.

You mean gravity batteries using concrete weights? A scam for suckers.

Making hydrogen from water and solar light is certainly better than using nuclear energy for that.

There is no reason for consuming valuable nuclear fuel, for which better uses exist, instead of using free solar light.

The efficiency of converting solar energy into hydrogen is already acceptable. The same is true for the efficiency of converting hydrogen and concentrated carbon dioxide into synthetic hydrocarbons, which are the best means for long term energy storage, and also for applications like aircraft and spacecraft.

The least efficient step remains concentrating the diluted carbon dioxide from air.

While the efficiency of converting solar energy and water into hydrogen by artificial means is already better than that of living beings, the living beings are still much more efficient in converting H2 and CO2 from air into organic substances.

Besides improving the efficiency of the existing techniques, an alternative method of CO2 capture would be the genetic engineering of a bacterium that would produce some usable oil from H2 and air, with an improved productivity over the existing bacteria, which use most of the captured energy to make substances useful for them, not for us, so unmodified bacteria would not have a high enough useful output.

IIRC nuclear doesn't really work well as the last 5-10%. Start-up and shut-down for nuclear reactors is a slow process. When it's generating, it needs to just keep on generating. Not so quick to dial down or up just because the wind is(n't) blowing.

Nuclear reactors make awful targets in a conflict, not sure having many around is generally a good idea if conflict is a risk and there are alternatives.

> The only thing that's actually tricky is synfuels and solar/battery doesn't solve that. High temperature reactors using heat to create hydrogen is arguable the better path to synfuels then electrolysis.

Found this interesting: https://phys.org/news/2026-02-microbial-eco-friendly-butanol.

That number is improbably low. Transmission losses from local power plants to consumers is on the order of 10%.

Cite, please?

It's nice for an emergency, and almost all EVs can do that already.

But people pay extra to put the batteries over wheels because they need to haul charged batteries around. It's not normally useful to discharge them locally.

Just charging your car when electricity is cheap and avoiding times when it is scarce would solve most of the issues, provided there is a dynamic pricing system in place.

We already have an electric grid we don’t need to build a new one from scratch just replace infrastructure that gets to old and add more for whatever extra demand shows up.

Obviously other energy sources are going to exist and non solar power will be produced, but nuclear is getting fucked in a solar + battery heavy future. Nuclear already needs massive subsidies and those subsidies will need to get increasingly large to keep existing nuclear around let alone convince companies to build more.

> Grid scale lithium batteries have an effective lifecycle of 15 years. In this potential future, global lithium reserves would actually start getting choked up before the 2050 goal.

I think the long-term solutions here are not grid-scale lithium batteries, but pumped hydro, flow batteries, or compressed air. Lithium batteries have just gotten a bit ahead on the technological growth curve because of the recent boom in production from phones and EVs, but liquid flow batteries can be made using common elements, and are likely to be cost-effective once the tech gets worked out better.

So: I don't think we can say "lithium energy storage is unfeasible large-scale and long-term" and thus conclude that nuclear is inevitable, unless we also look at all the other storage alternatives.

> That's assuming constant production of batteries at the current scale and production.

That's a terribly pessimistic assumption when production has been scaling exponentially, and cost per kWh dropping exponentially.