> The central finding is that a 15% increase in solar generation across the U.S. is associated with an annual reduction of 8.54 million metric tons (MMT) of CO2, a significant step toward national climate goals.
Given that solar power is 4% of electricity generation, a 15% increase is like 0.5% percentage points in total. Roughly 30% of co2 is from electricity generation, the numbers all seem to make sense.
If you replace 0.5% of things that emit carbon with non-carbon sources it reduces carbon emissions by 0.5%.
> We need vastly less total primary energy to run a 90-95% efficient BEV compared to a 20-30% thermally ICE.
While true, that requires actually transitioning to BEVs, which in turn requires having enough batteries to transition to BEVs.
Doing that in the USA is (~290M vehicles, say 60kWh each, ~= 17.4TWh) more than enough to provide the entire USA with several days worth of backup storage, even if the place somehow got a continent-wide version of a Dunkelflaute that wasn't merely "20% normal output" but "actually no output".
I am hopeful this will happen, but last I checked, it was further away than the PV itself is, what with the batteries needing replacement every few thousand cycles but the PV mostly lasting 25-35 years no problem.
For the net zero scenarios by the IEA one of the areas that is ahead of the curve is batteries.
The global battery manufacturing capacity reached 3 TWh in 2024.
With say an average lifetime of 15 years getting a bit over 1 TWh of new batteries per year for the car fleet seems easily feasible.
Then please give us a source for regarding your continental dunkelflate doomsday scenario so we can make sure is a plausible scenario, and not made up scary numbers.
Of course ignoring that you assume that we need to charge every single car to 100% every day.
> The global battery manufacturing capacity reached 3 TWh in 2024.
OK, that's better than I thought, I was led to believe it was 1 TWh in 2024.
> With say an average lifetime of 15 years getting a bit over 1 TWh of new batteries per year for the car fleet seems easily feasible.
I think that's optimistic; none of my (non-car) batteries have maintained significant capacity for that long. I think grid use will look more like phone or laptop use than like car use, with daily full cycles?
> Then please give us a source for regarding your continental dunkelflate doomsday scenario so we can make sure is a plausible scenario, and not made up scary numbers.
I think you're misunderstanding me on this. I'm saying it's good enough even for a very weird and unusual condition far in excess of the normal talking points.
> Of course ignoring that you assume that we need to charge every single car to 100% every day.
No? I'm saying I expect an average car to get a 60kWh battery pack, and that there are 290 million vehicles in the USA, and that this makes a combined manufacturing requirement of sustaining a capacity of multiply-those-numbers-together storage. This says nothing about how often that storage will normally get charged, and instead I was saying how long this could power the USA for if discharged in a very weird condition.
Actual power consumption of those vehicles is tiny, something like 80% of mean consumption (in places where shaded parking isn't the norm) could be supplied by requiring their surfaces to be covered in PV.
These kinds of arguments don't really add up if you use some system thinking and extrapolate from current trends.
First, the US isn't northern Europe (where solar energy is very popular regardless). Especially the southern half is more comparable to southern Europe or even North Africa. Places like Berlin are at 52 degrees latitude. You have to go deep into Canada to find cities at a similar latitude. Most of the US is below 49 degrees and gets decent amounts of sun. It's more than fine most of the year. If you regularly need to wear your sun glasses in January, you live in a place that can have solar power.
But sure, the Sun doesn't always shine and it gets grey and cloudy sometimes. Even in San Diego. But there are also wind, and batteries. And people always forget that you can use cables to move energy around as well. And a lot of cables aren't at their maximum capacities all of the time. So, they can be used to move energy around when it isn't needed and be used to charge batteries close to where it is needed later. San Diego is basically at the same latitude as places in Northern Africa that might end up supplying power via HVDC cables to Europe. The US can mix off shore wind on both coasts, solar across the south and its deserts with hydro in mountainous regions and lots of batteries. At this point very doable already and long term only getting more obvious to do as cost and efficiencies continue to improve.
Finally, modern batteries already last quite long. LFP and sodium ion are basically getting lifespans of 5000 or more cycles at this point. That's basically decades with normal usage and over a decade even with full daily cycling (which would be intensive usage).
Sodium ion means lots of dirt cheap batteries for storage and (small) vehicles. Basically it uses no rare materials and lasts a long time. It has the potential to decimate the cost of batteries from close to 100$/kwh to more like 10$/kwh by some estimates. At 10$/kwh, most house holds would be able to afford to have a mwh battery - enough to power an inefficient US household for a month. And a more efficient household throughout even the longest imaginable type of dunkelflaute. You can't quite get those yet of course but at this point we have some reason to be optimistic about this being possible mid to long term at least.
Add nuclear, hydro and geothermal to the mix and you have a lot of clean ways to generate and move around clean energy. That kind of system takes time to build but there really aren't a whole lot excuses not to.
This transition period has a lot of people looking in the rear view mirror being blind to the huge stuff that is clearly visible ahead at this point. There are a few wild cards that are interesting but not that essential. Like small reactors, fusion, etc. Nice but not really that essential.
The dunkelflaute is an interesting technical and infrastructure challenge that requires some out of the box thinking. But it's very solvable and it doesn't require any major new technology breakthroughs. We just need to do more of what we're already doing and preferably a bit cheaper. All very doable and within reach. And we have time to do it as our old infrastructure isn't magically about to disappear. Most of this stuff will be cost and economics driven.
Lots of countries that are ahead of the curve might be importing progressively less oil in the decades ahead. That means their trade balances shift and they start having economic growth and a competitive advantage.
IMHO countries that are lagging here will first fall behind, suffer the economic consequences for a while, and then fix it by compensating with massive investments. The US seems to be doing all the wrong things to set itself up for exactly that right now. Which is why I'm quite optimistic it will figure it out eventually.
I think you're arguing against something I didn't say?
The tech is great. I'm usually the one defending it, even. But you do actually have to build the factories. Which we (humanity, I'm not American) are, as fast as we can, but that's the trend-line to look at, not what the tech can ultimately do.
I mean, to one of your points, I'm one of the few people here who keeps saying that if China wanted to make it a strategic goal, they have the manufacturing capacity to put in a genuinely global power grid with 1Ω electrical resistance for a fairly low material cost (few hundred billion), what a shame about the geopolitical realities getting in the way of this…
Put another way, if I could grease the right palms to shave commensurate minuscule savings off of the budget of ICE, it'd pay off my mortgage. Twentyfold.
Back to greenhouse gases, I'm no climatologist, but isn't it plausible the difference could, for instance, make or break one catastrophic wildfire across the western seaboard of North America?
Beware of statistic thinking in a stochastic world.
Redefining coal as "solid oil" and natural gas as "gaseous oil" is ludicrous. Coal, natural gas and oil are well-defined concepts that are not easily fungible in our energy infrastructure, so plopping them all together using your made-up language is silly.
GGP used oil to cover all fossil fuel based sources.. GP decided to focus on the word choice rather than the intent. 58% of the worlds power comes from fossil fuels.
I don't think Jevon's Paradox is applicable here? This is about solar becoming more efficient.
In any case, if the argument is that oil is going to be pumped regardless of how much it's actually used, can we not just save it for a rainy day, so to speak?
No because we cannot store large amounts of oil. We can store a few weeks of oil, and that's it. That's why, for example, Putin burned it off: if he doesn't cut supply, he can't store it. But that isn't a Russian problem, that's a global problem.
Losses through burnoff are typical in the industry, which is why equipment for large scale burnoff even exists: for various logistical problems. If oil can't be taken out of pumps or refineries, and it's not worth it to take production offline due to restart costs, they just burn it right there. For no useful work.
The reason this is a stupid argument is that solar power is significantly cheaper than fossil fuel power almost everywhere. And not in a "calculating all of the global impacts" way, in the very direct, greedy, "I want the cheapest electricity possible" way. "Whatabout"s with storage and time of day, etc. aren't necessary, battery tech is cheap and solar production is so cheap you can do inefficient things with it (panels at non-ideal angles to get more power at off peak hours) and still come out ahead.
I really doubt China is installing solar at insane rates to be nice to the world.
The study compares a percentage increase of solar power against an absolute decrease of CO2 emissions.
This seems like questionable reasoning to me. If California has 100 MW of solar power for every 10 MW in Indiana, a 10% increase in solar will show up as 10x more CO2 savings for California just because it has a larger installed base.
To me the relevant question is the relative dirtiness of the nonrenewables being replaced, and the relative cost and effectiveness of solar. IMHO the data ought to be normalized to a per-MW-installed-rating basis.
I wish the study went like this (all the following numbers are completely made up, based on nothing more than the fertile imagination of an HN commentator mildly annoyed by the study's questionable numeracy):
- In California, clouds / latitude / etc. mean a panel's only usable 10/24 hours on average per day
- In Indiana, the geography's less ideal, so clouds / latitude / etc. make it usable 8/24 hours on an average day
- In California, it would be replacing a super-clean natural gas plant installed in 2008 that has expensive high-tech emissions control devices required by the super-strict California environmental regulations and emits 0.4 tons of CO2 per MWH.
- In Indiana, there was no money or political will for modern power plants or strict environmental regulations, so the solar panel would be replacing a smoke belching coal plant from the previous millenium that emits 1.2 tons of CO2 per MWH.
- In California, labor for >1 MW solar installations costs $0.20 / W, costs are inflated by high CoL / taxes and business unfriendly regulations but there are lots of firms with experience who can install quickly.
- In Indiana, labor for >1 MW solar installations is $0.15 / W, they pay a lot less and don't have as much red tape, which slightly outweighs the fact installers don't have much experience and bumble around being slow and making expensive mistakes.
- Your per-watt cost is $0.20 / (10/24) = $0.48 in California but $0.15 / (8/24) = $0.45 in Indiana (which is also your per-MW cost in millions).
- Your daily emissions reduction is 0.4 x 10 = 4.0 tons for California and 1.2 x 8 = 9.6 tons emissions reduction for Indiana.
- Therefore every $1M spent in California buys 4.0 / $0.48 = 8.3 tons / day of emissions reduction and every $1M spent in Indiana buys 9.6 / .45 = 21.3 tons / day of emissions reduction.
If you care about efficiently spending money to reduce emissions, in this example (using made-up numbers) Indiana is the low-hanging fruit, investments there are better by a factor of 21.3 / 8.3 ~ 2.6.
But the way the study's written, if we assume solar is currently 2000 MW for California and 200 MW for Indiana, its calculations would suggest a 10% increase in California (200 MW) would save 200 x 4.0 = 800 tons and a 10% increase in Indiana would save 20 x 9.6 = 192 tons.
This is very misleading.
If you don't think about the units and just look at the numbers, you might be tempted to conclude the study's telling you that California's emissions reduction rating is 800 and Indiana's rating is 192, so if you care about CO2 reduction every dollar of investment is a factor of 4 as effective in California -- when in reality, with these numbers every dollar is actually a factor of 2.6 more effective in Indiana.
> The study compares a percentage increase of solar power against an absolute decrease of CO2 emissions.
local CO2 emissions. This has not affected pumping of oil, and since we aren't even able to store much oil, that means it's getting burned. That makes it clear the global effect must be very close to zero. And for CO2, only global matters.
You're essentially arguing that reducing demand won't reduce supply. It may not do so immediately, but certainly over time it will.
For example, there are oil fields that are unexploited because they would not be profitable. If demand rose, prices would rise and new wells would be opened. The reverse is also true.
California has the opportunity to be a beacon in North America for environmental and climate action e.g. by expanding solar production, finishing the CAHSR, and other projects like expanding and electrifying mass transit and commuter rail networks, but they are their own worst enemy.
California has already fallen behind both Texas and Florida in new utility grade solar. As for CA-HSR, no comment. But if you don't want to wait, you can buy a ticket today and ride Florida's new high speed rail between Orlando and Miami.
The fact that Brightline can take you from Miami to Orlando is wonderful, and I'm really happy Florida is embracing more efficient, less dangerous, and less stressful forms of transportation.
But using it to make a subtle jab agains CAHSR isn't really fair -- they're two very different projects (for one of them, it's genuinely a stretch to call it "HSR") in two very different regions.
Yes, it's harder to get big projects through the red tape in California than it is in West / Panhandle Texas or Central Florida. Go take a drive through those regions and you'll quickly see some reasons why, besides just NIMBYism, Californians are a bit more protective of their landscapes. If a massive wind project were proposed across large swaths of the Texas Hillcountry, you'd see a lot more push-back.
> But using it to make a subtle jab agains CAHSR isn't really fair -- they're two very different projects (for one of them, it's genuinely a stretch to call it "HSR") in two very different regions.
Well, CA HSR doesn't exist. It's missing the R part of the HSR. So that must be the one it's a stretch to call "HSR".
Brightline is too slow to call it high speed. But we have it today which is worth something unlike maybe some year with all the other options - so brightline gets the win today. things are likely to change in the future but I don't see anything I'd bet on (but I only bet very sure things)
> or one of them, it's genuinely a stretch to call it "HSR"
How fast is California's HSR?
That's both sarcasm and an actual question. It doesn't go anywhere now but I keep hearing it's speed get downgraded as they encounter the real world. Plus, the goal of LA-SF is practically abandoned and now it takes you from a place you don't want to be to a place you don't want to go.
You really can't compare the two because one exists only as a goal and the other is an accomplishment.
>EIA publishes hourly operational data across the United States electricity grid, including demand, net generation of electricity from various sources (such as coal, natural gas, solar), CO2 emissions, import/export to other regions, and many more. The complete details of the EIA-930 data is available here: https://www.eia.gov/electricity/gridmonitor/about. Furthermore, we obtained the solar capacities of each year and each region from EIA (https://www.eia.gov/electricity/data/state/) and had stored the information in the file solar_capacity_factor.csv. (2023-07-01)
And "California" is a huge area. I doubt that the entire state is ideal for solar. I was hoping to see an actual map and zoom in on my neighborhood. I want to know if it makes sense to install on my house. This is zero help.
You need to ask a contractor to check your roof orientation and potential shade sources (trees, big mountain? You should be aware about those already). Other factors are pretty much not relevant. Also remember that light, not sun shine, matters. Light clouds might still allow the panels to work very efficiently.
> In some areas, such as California, Florida, the mid-Atlantic, the Midwest, Texas and the Southwest, small increases in solar were estimated to deliver large CO2 reductions, while in others, such as New England, the central U.S., and Tennessee, impacts were found to be minimal
In addition to what @adrianN says about the laws (which is very true, these things are extremely easy to setup, install, and even to register despite the reputation of German bureaucracy), PV is also absurdly cheap.
We've got one. As per the law, limited to 800 W. €350 (of which €50 was delivery), including the inverter and the stands. As it happens, the stands weren't too useful for us (didn't fit our balcony so the panels are now on the driveway) and we could've reduced that to €250 if we'd gone for a model without stands and had been able to pick the kit up in person rather than getting delivered.
But even at €350, assuming 10% capacity factor, €350/(800W*24h*10%*€0.3/kWh*365) = 1.665 years = 1y8m.
Even if electricity was a third of the price, even with the €350 we spent, these things would still be no-brainers because they would still pay for themselves five to seven times over in their expected lifespans. As is, 15-21 times over.
Germany in H2 2024 was at €0.3943 per KWh including standing charges [0], so not quite the right number when evaluating whether balcony solar is worth it.
This sort of study is dumb as it misses the bigger picture.
The focus on CO2 is for climate purposes. If one is genuinely concerned about the environment then one would look at all power generation technologies, not only solar. If one did this then solar would not be a focus of concern for power generation. Articles like this one suggest that solar is an answer to climate change, when, at best, it is a distraction.
I agree that this kind of exercise is only academic in nature and mostly useless pragmatically once you layer in the complexities of energy markets.
I actually would say the solutions to climate change from a grid perspective are pretty straightforward but tough to implement. New generation: Large nuclear hubs, smrs, solar and battery. hydro and wind as is.
> The central finding is that a 15% increase in solar generation across the U.S. is associated with an annual reduction of 8.54 million metric tons (MMT) of CO2, a significant step toward national climate goals.
Whoa, that's really cool.
You can see the paper along with figures & regional breakdowns here: https://openpaper.ai/paper/share/1d0c6956-4820-4ee2-ac1e-12c...
Seems odd to state a percentage increase in solar to obtain an absolute decrease in CO2.
US Produced about 4.8 Billion Metric Tons of CO2 in 2024 ( https://www.statista.com/statistics/183943/us-carbon-dioxide... )
The savings is minuscule. But important nonetheless. It just goes on to show how much more solar is required.
Given that solar power is 4% of electricity generation, a 15% increase is like 0.5% percentage points in total. Roughly 30% of co2 is from electricity generation, the numbers all seem to make sense.
If you replace 0.5% of things that emit carbon with non-carbon sources it reduces carbon emissions by 0.5%.
This falls for the ”fallacy” of primary energy.
We need vastly less total primary energy to run a 90-95% efficient BEV compared to a 20-30% efficient ICE.
That is excluding the entire very inefficient supply chain to refine and transport the fuel to the ICE.
> We need vastly less total primary energy to run a 90-95% efficient BEV compared to a 20-30% thermally ICE.
While true, that requires actually transitioning to BEVs, which in turn requires having enough batteries to transition to BEVs.
Doing that in the USA is (~290M vehicles, say 60kWh each, ~= 17.4TWh) more than enough to provide the entire USA with several days worth of backup storage, even if the place somehow got a continent-wide version of a Dunkelflaute that wasn't merely "20% normal output" but "actually no output".
I am hopeful this will happen, but last I checked, it was further away than the PV itself is, what with the batteries needing replacement every few thousand cycles but the PV mostly lasting 25-35 years no problem.
For the net zero scenarios by the IEA one of the areas that is ahead of the curve is batteries.
The global battery manufacturing capacity reached 3 TWh in 2024.
With say an average lifetime of 15 years getting a bit over 1 TWh of new batteries per year for the car fleet seems easily feasible.
Then please give us a source for regarding your continental dunkelflate doomsday scenario so we can make sure is a plausible scenario, and not made up scary numbers.
Of course ignoring that you assume that we need to charge every single car to 100% every day.
> The global battery manufacturing capacity reached 3 TWh in 2024.
OK, that's better than I thought, I was led to believe it was 1 TWh in 2024.
> With say an average lifetime of 15 years getting a bit over 1 TWh of new batteries per year for the car fleet seems easily feasible.
I think that's optimistic; none of my (non-car) batteries have maintained significant capacity for that long. I think grid use will look more like phone or laptop use than like car use, with daily full cycles?
> Then please give us a source for regarding your continental dunkelflate doomsday scenario so we can make sure is a plausible scenario, and not made up scary numbers.
I think you're misunderstanding me on this. I'm saying it's good enough even for a very weird and unusual condition far in excess of the normal talking points.
> Of course ignoring that you assume that we need to charge every single car to 100% every day.
No? I'm saying I expect an average car to get a 60kWh battery pack, and that there are 290 million vehicles in the USA, and that this makes a combined manufacturing requirement of sustaining a capacity of multiply-those-numbers-together storage. This says nothing about how often that storage will normally get charged, and instead I was saying how long this could power the USA for if discharged in a very weird condition.
Actual power consumption of those vehicles is tiny, something like 80% of mean consumption (in places where shaded parking isn't the norm) could be supplied by requiring their surfaces to be covered in PV.
These kinds of arguments don't really add up if you use some system thinking and extrapolate from current trends.
First, the US isn't northern Europe (where solar energy is very popular regardless). Especially the southern half is more comparable to southern Europe or even North Africa. Places like Berlin are at 52 degrees latitude. You have to go deep into Canada to find cities at a similar latitude. Most of the US is below 49 degrees and gets decent amounts of sun. It's more than fine most of the year. If you regularly need to wear your sun glasses in January, you live in a place that can have solar power.
But sure, the Sun doesn't always shine and it gets grey and cloudy sometimes. Even in San Diego. But there are also wind, and batteries. And people always forget that you can use cables to move energy around as well. And a lot of cables aren't at their maximum capacities all of the time. So, they can be used to move energy around when it isn't needed and be used to charge batteries close to where it is needed later. San Diego is basically at the same latitude as places in Northern Africa that might end up supplying power via HVDC cables to Europe. The US can mix off shore wind on both coasts, solar across the south and its deserts with hydro in mountainous regions and lots of batteries. At this point very doable already and long term only getting more obvious to do as cost and efficiencies continue to improve.
Finally, modern batteries already last quite long. LFP and sodium ion are basically getting lifespans of 5000 or more cycles at this point. That's basically decades with normal usage and over a decade even with full daily cycling (which would be intensive usage).
Sodium ion means lots of dirt cheap batteries for storage and (small) vehicles. Basically it uses no rare materials and lasts a long time. It has the potential to decimate the cost of batteries from close to 100$/kwh to more like 10$/kwh by some estimates. At 10$/kwh, most house holds would be able to afford to have a mwh battery - enough to power an inefficient US household for a month. And a more efficient household throughout even the longest imaginable type of dunkelflaute. You can't quite get those yet of course but at this point we have some reason to be optimistic about this being possible mid to long term at least.
Add nuclear, hydro and geothermal to the mix and you have a lot of clean ways to generate and move around clean energy. That kind of system takes time to build but there really aren't a whole lot excuses not to.
This transition period has a lot of people looking in the rear view mirror being blind to the huge stuff that is clearly visible ahead at this point. There are a few wild cards that are interesting but not that essential. Like small reactors, fusion, etc. Nice but not really that essential.
The dunkelflaute is an interesting technical and infrastructure challenge that requires some out of the box thinking. But it's very solvable and it doesn't require any major new technology breakthroughs. We just need to do more of what we're already doing and preferably a bit cheaper. All very doable and within reach. And we have time to do it as our old infrastructure isn't magically about to disappear. Most of this stuff will be cost and economics driven.
Lots of countries that are ahead of the curve might be importing progressively less oil in the decades ahead. That means their trade balances shift and they start having economic growth and a competitive advantage.
IMHO countries that are lagging here will first fall behind, suffer the economic consequences for a while, and then fix it by compensating with massive investments. The US seems to be doing all the wrong things to set itself up for exactly that right now. Which is why I'm quite optimistic it will figure it out eventually.
I think you're arguing against something I didn't say?
The tech is great. I'm usually the one defending it, even. But you do actually have to build the factories. Which we (humanity, I'm not American) are, as fast as we can, but that's the trend-line to look at, not what the tech can ultimately do.
I mean, to one of your points, I'm one of the few people here who keeps saying that if China wanted to make it a strategic goal, they have the manufacturing capacity to put in a genuinely global power grid with 1Ω electrical resistance for a fairly low material cost (few hundred billion), what a shame about the geopolitical realities getting in the way of this…
Gigatonnes for short, as used in climate sciences.
I mean it's five basis points, it ain't nothin.
Put another way, if I could grease the right palms to shave commensurate minuscule savings off of the budget of ICE, it'd pay off my mortgage. Twentyfold.
Back to greenhouse gases, I'm no climatologist, but isn't it plausible the difference could, for instance, make or break one catastrophic wildfire across the western seaboard of North America?
Beware of statistic thinking in a stochastic world.
Fifty basis points.
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Solar is cheaper than oil, and oil is essentially never used for electricity.
Of the world's power 35% is coal (solid oil), 20% Gas/Natural Gas (gaseous oil), 3% oil (Wikipedia def'n).. 58% of our power is oil https://en.wikipedia.org/wiki/List_of_countries_by_electrici...
Are you being particular about your definition of oil?
Light Oil (C4-C12 aka "Gasoline"(NA) "Petrol"(EU)) is used for personal generation and backup power systems.
Heavy oil (C9-C25 aka "Diesel") is regularly used for electricity, extensively used for backup power systems.
Redefining coal as "solid oil" and natural gas as "gaseous oil" is ludicrous. Coal, natural gas and oil are well-defined concepts that are not easily fungible in our energy infrastructure, so plopping them all together using your made-up language is silly.
GGP used oil to cover all fossil fuel based sources.. GP decided to focus on the word choice rather than the intent. 58% of the worlds power comes from fossil fuels.
I count three percent as negligible.
I don't think Jevon's Paradox is applicable here? This is about solar becoming more efficient.
In any case, if the argument is that oil is going to be pumped regardless of how much it's actually used, can we not just save it for a rainy day, so to speak?
No because we cannot store large amounts of oil. We can store a few weeks of oil, and that's it. That's why, for example, Putin burned it off: if he doesn't cut supply, he can't store it. But that isn't a Russian problem, that's a global problem. Losses through burnoff are typical in the industry, which is why equipment for large scale burnoff even exists: for various logistical problems. If oil can't be taken out of pumps or refineries, and it's not worth it to take production offline due to restart costs, they just burn it right there. For no useful work.
Why can't we store oil? Is it just a matter of we haven't built long-term storage yet due to not needing to, or is there something else?
We can store oil underground for millions of years.
The reason this is a stupid argument is that solar power is significantly cheaper than fossil fuel power almost everywhere. And not in a "calculating all of the global impacts" way, in the very direct, greedy, "I want the cheapest electricity possible" way. "Whatabout"s with storage and time of day, etc. aren't necessary, battery tech is cheap and solar production is so cheap you can do inefficient things with it (panels at non-ideal angles to get more power at off peak hours) and still come out ahead.
I really doubt China is installing solar at insane rates to be nice to the world.
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Direct study link (with associated diagrams): https://www.science.org/doi/10.1126/sciadv.adq5660
The study compares a percentage increase of solar power against an absolute decrease of CO2 emissions.
This seems like questionable reasoning to me. If California has 100 MW of solar power for every 10 MW in Indiana, a 10% increase in solar will show up as 10x more CO2 savings for California just because it has a larger installed base.
To me the relevant question is the relative dirtiness of the nonrenewables being replaced, and the relative cost and effectiveness of solar. IMHO the data ought to be normalized to a per-MW-installed-rating basis.
I wish the study went like this (all the following numbers are completely made up, based on nothing more than the fertile imagination of an HN commentator mildly annoyed by the study's questionable numeracy):
- In California, clouds / latitude / etc. mean a panel's only usable 10/24 hours on average per day
- In Indiana, the geography's less ideal, so clouds / latitude / etc. make it usable 8/24 hours on an average day
- In California, it would be replacing a super-clean natural gas plant installed in 2008 that has expensive high-tech emissions control devices required by the super-strict California environmental regulations and emits 0.4 tons of CO2 per MWH.
- In Indiana, there was no money or political will for modern power plants or strict environmental regulations, so the solar panel would be replacing a smoke belching coal plant from the previous millenium that emits 1.2 tons of CO2 per MWH.
- In California, labor for >1 MW solar installations costs $0.20 / W, costs are inflated by high CoL / taxes and business unfriendly regulations but there are lots of firms with experience who can install quickly.
- In Indiana, labor for >1 MW solar installations is $0.15 / W, they pay a lot less and don't have as much red tape, which slightly outweighs the fact installers don't have much experience and bumble around being slow and making expensive mistakes.
- Your per-watt cost is $0.20 / (10/24) = $0.48 in California but $0.15 / (8/24) = $0.45 in Indiana (which is also your per-MW cost in millions).
- Your daily emissions reduction is 0.4 x 10 = 4.0 tons for California and 1.2 x 8 = 9.6 tons emissions reduction for Indiana.
- Therefore every $1M spent in California buys 4.0 / $0.48 = 8.3 tons / day of emissions reduction and every $1M spent in Indiana buys 9.6 / .45 = 21.3 tons / day of emissions reduction.
If you care about efficiently spending money to reduce emissions, in this example (using made-up numbers) Indiana is the low-hanging fruit, investments there are better by a factor of 21.3 / 8.3 ~ 2.6.
But the way the study's written, if we assume solar is currently 2000 MW for California and 200 MW for Indiana, its calculations would suggest a 10% increase in California (200 MW) would save 200 x 4.0 = 800 tons and a 10% increase in Indiana would save 20 x 9.6 = 192 tons.
This is very misleading.
If you don't think about the units and just look at the numbers, you might be tempted to conclude the study's telling you that California's emissions reduction rating is 800 and Indiana's rating is 192, so if you care about CO2 reduction every dollar of investment is a factor of 4 as effective in California -- when in reality, with these numbers every dollar is actually a factor of 2.6 more effective in Indiana.
There is no "super clean natural gas plant" you're still burning a nonrenewable hydrocarbon and letting its carbon go into the atmosphere
> The study compares a percentage increase of solar power against an absolute decrease of CO2 emissions.
local CO2 emissions. This has not affected pumping of oil, and since we aren't even able to store much oil, that means it's getting burned. That makes it clear the global effect must be very close to zero. And for CO2, only global matters.
You're essentially arguing that reducing demand won't reduce supply. It may not do so immediately, but certainly over time it will.
For example, there are oil fields that are unexploited because they would not be profitable. If demand rose, prices would rise and new wells would be opened. The reverse is also true.
California has the opportunity to be a beacon in North America for environmental and climate action e.g. by expanding solar production, finishing the CAHSR, and other projects like expanding and electrifying mass transit and commuter rail networks, but they are their own worst enemy.
California has already fallen behind both Texas and Florida in new utility grade solar. As for CA-HSR, no comment. But if you don't want to wait, you can buy a ticket today and ride Florida's new high speed rail between Orlando and Miami.
The fact that Brightline can take you from Miami to Orlando is wonderful, and I'm really happy Florida is embracing more efficient, less dangerous, and less stressful forms of transportation.
But using it to make a subtle jab agains CAHSR isn't really fair -- they're two very different projects (for one of them, it's genuinely a stretch to call it "HSR") in two very different regions.
Yes, it's harder to get big projects through the red tape in California than it is in West / Panhandle Texas or Central Florida. Go take a drive through those regions and you'll quickly see some reasons why, besides just NIMBYism, Californians are a bit more protective of their landscapes. If a massive wind project were proposed across large swaths of the Texas Hillcountry, you'd see a lot more push-back.
> But using it to make a subtle jab agains CAHSR isn't really fair -- they're two very different projects (for one of them, it's genuinely a stretch to call it "HSR") in two very different regions.
Well, CA HSR doesn't exist. It's missing the R part of the HSR. So that must be the one it's a stretch to call "HSR".
Brightline is too slow to call it high speed. But we have it today which is worth something unlike maybe some year with all the other options - so brightline gets the win today. things are likely to change in the future but I don't see anything I'd bet on (but I only bet very sure things)
Also, fwiw, we've had an HSR project in the works in Texas for a couple decades now and have yet to even make a solid plan, much less break ground.
> or one of them, it's genuinely a stretch to call it "HSR"
How fast is California's HSR?
That's both sarcasm and an actual question. It doesn't go anywhere now but I keep hearing it's speed get downgraded as they encounter the real world. Plus, the goal of LA-SF is practically abandoned and now it takes you from a place you don't want to be to a place you don't want to go.
You really can't compare the two because one exists only as a goal and the other is an accomplishment.
Brightline’s muni bonds have been downgraded to highly speculative. Ride while you can.
https://www.fitchratings.com/research/infrastructure-project...
https://www.bloomberg.com/news/articles/2025-07-11/florida-s... | https://archive.today/LEyBC
Brightline is a diesel train that runs 80-125 mph (130-200 kmh) though, that can hardly be called HSR. In Europe or Asia that is just called "rail".
That high speed rail is not electric unlike high speed rail in Europe or Japan or China. It doesn't deliver enough climate benefits.
A diesel train releases orders of magnitudes less CO2 than flights though.
modern diesel is extremely clean, and when compared to air travel, the benefits are clear, both in cost and in carbon emissions
GH project with a link to the data and the instructions how to process it https://github.com/NSAPH-Projects/green-energy-optimization
"raw data" is from EIA (a veritable rabbit hole!)
>EIA publishes hourly operational data across the United States electricity grid, including demand, net generation of electricity from various sources (such as coal, natural gas, solar), CO2 emissions, import/export to other regions, and many more. The complete details of the EIA-930 data is available here: https://www.eia.gov/electricity/gridmonitor/about. Furthermore, we obtained the solar capacities of each year and each region from EIA (https://www.eia.gov/electricity/data/state/) and had stored the information in the file solar_capacity_factor.csv. (2023-07-01)
except there's no map!
And "California" is a huge area. I doubt that the entire state is ideal for solar. I was hoping to see an actual map and zoom in on my neighborhood. I want to know if it makes sense to install on my house. This is zero help.
You need to ask a contractor to check your roof orientation and potential shade sources (trees, big mountain? You should be aware about those already). Other factors are pretty much not relevant. Also remember that light, not sun shine, matters. Light clouds might still allow the panels to work very efficiently.
Verb vs noun
It's like reading an article about a painting. I think this might be the worst experience.
you had one job!
> In some areas, such as California, Florida, the mid-Atlantic, the Midwest, Texas and the Southwest, small increases in solar were estimated to deliver large CO2 reductions, while in others, such as New England, the central U.S., and Tennessee, impacts were found to be minimal
When I read "map", I think "map"...
This kind of reasoning and technology would never have predicted the surge in popularity of patio solar in Germany.
Germany electricity:
€0.3943 / kWh
That's about US$0.46 or AU$0.71 per kWh
That largely explains the surge in popularity of patio solar in Germany.
In addition to what @adrianN says about the laws (which is very true, these things are extremely easy to setup, install, and even to register despite the reputation of German bureaucracy), PV is also absurdly cheap.
We've got one. As per the law, limited to 800 W. €350 (of which €50 was delivery), including the inverter and the stands. As it happens, the stands weren't too useful for us (didn't fit our balcony so the panels are now on the driveway) and we could've reduced that to €250 if we'd gone for a model without stands and had been able to pick the kit up in person rather than getting delivered.
But even at €350, assuming 10% capacity factor, €350/(800W*24h*10%*€0.3/kWh*365) = 1.665 years = 1y8m.
Even if electricity was a third of the price, even with the €350 we spent, these things would still be no-brainers because they would still pay for themselves five to seven times over in their expected lifespans. As is, 15-21 times over.
Just a small correction but 39cts is a pretty bad price even for Germany.
You'll typically get ~30 these days with minimal comparison.
Still expensive but a full quarter less.
And mostly coming from taxes. The wholesale price and plus covering the subsidies would lead to a much lower cost.
Good to know
The important part of making it popular was changing laws to make it dead simple to install.
The important part is cheap abundant energy obviates the need for the average person to have to worry about being their own electricity generator.
Germany in H2 2024 was at €0.3943 per KWh including standing charges [0], so not quite the right number when evaluating whether balcony solar is worth it.
[0] https://ec.europa.eu/eurostat/statistics-explained/index.php...
On Mercury
Funded by US taxpayers via 11 grants, predominantly from NIH with additional institutional support from Harvard University.
This sort of study is dumb as it misses the bigger picture.
The focus on CO2 is for climate purposes. If one is genuinely concerned about the environment then one would look at all power generation technologies, not only solar. If one did this then solar would not be a focus of concern for power generation. Articles like this one suggest that solar is an answer to climate change, when, at best, it is a distraction.
I agree that this kind of exercise is only academic in nature and mostly useless pragmatically once you layer in the complexities of energy markets.
I actually would say the solutions to climate change from a grid perspective are pretty straightforward but tough to implement. New generation: Large nuclear hubs, smrs, solar and battery. hydro and wind as is.