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Cake day: March 22nd, 2026

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  • It’s hapening already if you look at birth rates.

    That’s why I’m skeptical of degrowth actually doing something to effectively reduce consumption. Because some individuals consume 3, maybe 4 orders of magnitude more resources (and the accompanying pollution or ecological destruction, however you want to measure it), I’ve always believed that reducing population runs a significant risk that the remaining smaller population will use far more resources than the previous larger population.

    You see it in rich countries. We have low birth rates and high consumption rates, and our consumption grows exponentially even as our population does not. We run a serious risk of being very destructive childless retirees, and consumption and pollution and emissions and ecological impact need to still be worked on, even if we do shrink the population.


  • They’re omitting the fact, that a lot of the biomass we’re eating comes from farming. Those plants that collect carbon dioxide from the atmosphere use a lot of synthetic fertilizers to grow, which itself uses A LOT of fossil energy to be produced.

    The CO2 emissions per calorie of food varies almost 3 whole orders of magnitude between different food types:

    https://ourworldindata.org/grapher/ghg-kcal-poore

    At the same time, our CO2 exhalation is about the same per calorie of food, regardless of source. So it’s more fair to describe our baseline biological needs and bodily functions separately from our economic consumption of the products we prefer to consume (food or otherwise).

    So I still think the focus on the raw calorie count of our consumption (and the accompanying CO2 exhalation) obscures, rather than explains, how our food consumption contributes to climate change.



  • Exactly. Cutting out all net resource consumption is really difficult, but almost all of the difficulty tends to come in the second half. The first half is worth doing.

    Somewhat counterintuitively, switching from a 15 mpg vehicle to a 20 mpg vehicle (and driving the same number of miles) represents a greater reduction in fuel consumption compared to switching from 20 mpg to 30 mpg. Side note, this is also why we probably should’ve always been talking about fuel consumption per unit distance rather than distance per unit fuel, but it’s hard to change the conventions around this.

    So there are a ton of examples of products that use far more or less energy than alternatives, or simple changes in time of day that can make a huge difference in fossil fuel demand.



  • I’m hopeful it will be good for aviation. It’s pretty hard to compete with kerosene’s 46.2 MJ/kg. The best batteries today are around 300 Wh/kg in commercial use, and some labs have hit 700+ Wh/kg. But with a MJ being equal to 278 Wh, we’re still talking 20-50x the energy density by weight. And that’s before even talking about how chemical fuels that are burned off leave less weight behind for the remaining vehicle, whereas a discharged battery weighs pretty much the same as a fully charged battery.

    Also, if we do move to storing energy in chemical bonds, pulling carbon out of the air, that basically turns into a carbon sequestration technique with whatever excess solar/wind energy we end up with, especially if we intentionally overbuild the capacity for non-peak production, and leave a method for using that energy during peak periods.



  • sparkyshocks@lemmy.ziptoScience Memes@mander.xyzNot a single one
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    25 days ago

    Yes, the specific accounting rules make the line between “profit” and “loss” fuzzy at times, but however you slice it, nuclear power costs a lot of resources for the amount of electricity that it produces. The money represents an opportunity cost of engineering effort and concrete and steel and equipment manufacturing and mining that could have been steered towards other types of projects.

    I’m agnostic towards the technology itself, but the economics of nuclear power just don’t make sense in the current environment, where we know that any new plants will get undercut by technologies that are already on the market today (solar+wind+batteries), technologies right around the corner (advanced geothermal), and even technologies that might be commercialized (fusion) within the 50-80 year lifespan of any new fission plant. That’s the competition, and I don’t think new nuclear plants are gonna be able to compete with those other technologies on cost.


  • sparkyshocks@lemmy.ziptoScience Memes@mander.xyzNot a single one
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    25 days ago

    Assuming theyre above with a cost of electricity of ~$0.20/kWh

    Can we assume that, after factoring in the actual portion that the accounting says goes to the power plant itself? The economics of utility scale electricity includes both generation and transmission, so you can’t just take that retail price and assume it all goes to the power plant that produced the electricity.

    Wholesale prices tend to stay below 10 cents in most parts of the country, although it sometimes spikes when grids are under strain. I think that’s probably a more fair assumption of how much the power plants themselves are paid for their production.


  • sparkyshocks@lemmy.ziptoScience Memes@mander.xyzNot a single one
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    25 days ago

    Public services (or even non-profit private organizations) still need to manage their resources efficiently. If the output of the service (number of meals fed to people, kilowatt hours produced, houses built, lives saved, passenger kilometers transported) is much smaller on a per dollar basis than comparable services, without good reason, then that organization is mismanaging resources.

    Plenty of public services can and do break even, or bring in more than they cost.

    Money is, in many ways, fake. But its accounting represents something real, in the real resources involved: land, human labor, physical materials like concrete and steel and copper that need to be turned into very complex equipment that require highly trained workers to operate and maintain.

    So when a project doesn’t break even, it’s worth asking whether the project is still worthwhile, whether the external benefits outweigh the localized costs. I don’t think modern nuclear passes that test (even if I believe that already-constructed nuclear should be extended as long as possible and operated at as close to full capacity as possible, because those up-front costs are already sunk).


  • Just think about it in terms of the number of people and number of days per year where they need to raise the indoor temperature by a certain amount, compared to the number of people and days needing to lower the temperature.

    If you’re looking at a place where it’s 95°F during the day and 85°F at night, and you like to set the temperature to 75°F, you’re only cooling it 10-20°F by time of day.

    But if you’re looking at a place where it’s 35°F during the day and 15°F at night, and you want to heat things up to 65°F, you’ve gotta change the temperature by 30-50°F throughout the day.

    Even when you’re comparing absurdly hot weather to absurdly cold weather, you’re still comparing something like 110°F to 0°F. You’re still looking at a 70°F swing versus a 35°F swing towards comfort.

    Throw in the fact that combustion of fuels (fossil fuels like heating oil or natural gas, or other fuels like wood in a fireplace) is usually only about 1/3 or 1/4 as energy efficient than the equivalent temperature change by heat pump, and you can see how much more energy intensive the typical indoor heating setup is compared to the typical indoor cooling setup.

    Some of it is obscured by the fact that fossil fuels are much cheaper per unit energy than electricity from the grid, so that heating bills aren’t as expensive in the same ratio, but in terms of actual energy used, it’s a big difference.



  • There are a few different reasons why.

    • The US already built up its rail network around low speed trains. Those tracks aren’t suitable for high speed operations, and can’t be modified easily for high speed operations. It’s not just the tracks themselves, it’s the actual paths and bridges and road crossings. If a turn is too sharp, it can’t be taken at high speeds, and the actual curves in the path didn’t anticipate that one day trains would be fast enough to need more gradual turns. So any new rail would have to buy up the land rights with any new pathway, and that is going to be inherently expensive in the corridors dense enough to where there might be demand for passenger rail.
    • Rail crossings have to be designed for high speed rail, as well. There are safety and congestion concerns, so many high speed rail projects are required to build more grade separated crossings (bridges and tunnels), which significantly increases construction costs.
    • Rail has to compete with air travel and highway travel, in a country rich enough to have lots of people who can afford to fly, and where car-based highway systems are convenient and cheap. Basically, there’s a sweet spot of around 200-400 miles (300-600 km) between cities where it’s far enough that a car is inconvenient and close enough to where trains are competitive with buses or airplanes.
    • Along those lines, the US actually has pretty cheap intercity buses that use the existing highways.
    • Unfortunately, the city pairs that would have the highest intercity passenger demand also tend to pass through a lot of other cities. If you’re going from DC to New York, the most popular rail line in America, you’ll pass through Baltimore, Wilmington, Philadelphia, and Trenton, each with their own powerful politicians who would push to make sure the train actually stops for them. This is part of why the Acela, our fastest passenger train, takes 190 minutes to travel 226 miles between DC and New York, averaging only 70 mph (115 km/h) despite being capable of reaching top speeds of 160 mph (255 km/h).
    • Most rail in the United States is owned by freight/cargo train lines. The passenger network has to lease spots and is lower priority than freight. This leads to scheduling issues, including unscheduled delays.
    • Americans are just really bad at constructing big public works projects. Our dams, bridges, tall buildings, rail, highways, roads, power plants, and all sorts of other big projects are almost always behind schedule and over budget.
    • The less populated areas where it’s cheaper to acquire land rights also tend to be more environmentally pristine, which means there are environmental concerns around projects like these. In our political system, Republicans are much more likely to ignore those environmental concerns, but they use that political clout to build highways and oil pipelines, not passenger rail. Advocates for passenger rail tend to also be more environmentally conscious, so the environmental concerns do tend to slow down any proposed rail project.

    There is high speed rail called Brightline in Florida between Miami and Orlando, with the longest segment operating at 125 mph (200 km/h), and some of the more populous segments operating at 110 mph/180 km/h or 80 mph/130 km/h. It tries to manage those tradeoffs on all new track dedicated to it. But the company is struggling to make money.

    There’s a whole saga in California in that the proposed high speed rail project is decades behind and still bogged down, and has examples of all of these problems. The route it takes to connect the two largest cities on the coast (Los Angeles and San Francisco) goes through the inland central valley, to service a bunch of other cities in between. Bizarrely, phase 1 of the project will only serve the relatively low density, low population cities in the Central Valley, without connecting either San Francisco or Los Angeles. Some segments are to share rail usage with lower speed trains, complicating scheduling and risking delays. The environmental debates have slowed things down, as well.

    Watch what happens in Texas with its proposed high speed line (bogged down in political infighting), Florida (see above, already built and operational, but facing serious financial concerns about its ability to continue), and California (see above).

    I think we’ll eventually see some projects push through, especially if jet fuel gets more expensive than electrical grid power. But for now, America is uniquely hostile to passenger rail, and increasing high speed offerings isn’t necessarily going to induce enough demand for these projects to become economically competitive with other forms of intercity transportation.



  • sparkyshocks@lemmy.ziptoScience Memes@mander.xyz*Permanently Deleted*
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    28 days ago

    That’s true of the metabolic pathways for fat, protein, and alcohol, too. Each oxygen molecule we breathe feeds into chemical reactions so that it picks up a carbon atom and becomes CO2 on the way out. The carbon comes from whatever food was metabolized, including anaerobic respiration where the lactic acid eventually gets cleared out.


  • Yes, but this published finding is interesting because it reduces the steps.

    Anyone can extract the elemental lithium from lithium cells, but it takes a lot of energy and harsh solvents and creates a lot of waste byproducts.

    But extracting lithium iron phosphate (LFP) salts is much less energy intensive, if those salts can be reused. This paper shows that LFP can be extracted and then reused as an ingredient in creating LMFP, a cathode material with higher performance characteristics.

    This is akin to using a technique to filter water instead of cracking it into hydrogen and oxygen and reconstituting the elements back as water.



  • I was flabbergasted the first time I realized just how far north Europe is, compared to North America.

    Paris is at 48° 51’ N, significantly further north than Toronto (43° N), Montreal (45° N). London is at 51°N 30’, which is further north than Vancouver (49° N), and just slightly further north than Calgary (51°N).

    Even southern European cities like Ibiza (39° N) are at comparable latitudes to northern American cities like Philadelphia (40°N) or even New York (41°N).

    If Europe starts seeing climate comparable to similar latitudes in North America, that would represent a huge change from the recorded history.