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Cake day: March 22nd, 2026

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  • A lot of the grid power still based on fossil fuels or coal

    Even if you of a long tailpipe emissions analysis of pure coal power, the total emissions are still lower than a comparable gasoline powered engine.

    Coal emits about 2.31 lbs (1.05 kg) of carbon dioxide per kwh.

    Gasoline emits about 20 lbs (8.9 kg) of carbon dioxide per gallon burned.

    So a car that gets 3.5 miles per kWh and is purely charged on coal emits about 0.3 kg of carbon per mile. A car that runs on gasoline and gets 30 miles per gallon is about the same.

    In comparison, natural gas is about 0.96lbs of CO2 per kWh, so that EV charged on natural gas would emit roughly the same as a 74 mile per gallon vehicle.

    Note that currently, in the US, coal is about 16% of electricity production, and natural gas is 41%. If you compare the emissions to the overall mix, you’ll get even lower numbers for the EV emissions.



  • Exactly. Engine displacement is just one number, and there have been major paradigm shifts in designs to squeeze way better performance and efficiency out of those engines across a wide range of RPMs: switching from carburetors to fuel injection, developing variable valve timing, better transmissions/traction control systems for actually get that torque and power on the ground.

    Plus, like, the rise of EVs, or even performance hybrids, has shown that you can have ultra high performance without any displacement at all.

    Looking back at the muscle cars of the 1970’s, where the idea came from, it’s crazy how huge those engines were, compared to 0-60 and quarter mile times that just weren’t that impressive by the 90’s, much less today. The 1970 Chevelle SS 454 had a 7.4L engine at 450 hp, but only got a 5.4s 0-62 and a 13.8s quarter mile. In 1995, the Toyota Supra put up similar performance with a 3.0L, 280 HP engine (although back then the Japanese manufacturers had some kind of gentleman’s agreement not to exceed 280hp in a way that tended to understate their overall performance). Today, Tesla literally manufactures a family friendly 3-row SUV that blows those numbers away. Scrolling through a list of cars that have sub-10 second quarter mile times off the factory floor, most of them have at least hybrid drivetrains where electric motors boost the overall torque and power.

    Relying on displacement these days is just giving up.



  • Your thesis doesn’t match up with this chart:

    https://ourworldindata.org/emissions-by-sector

    We’re working to decarbonize the highest categories on that list, with rapid adoption of solar/wind, some potential for more nuclear and geothermal in the medium term, and maybe even fusion in the long term.

    Then, while decarbonizing electricity, we’re electrifying heating for homes, water, cooking, and we’re electrifying transportation.

    US carbon emissions per capita peaked in the 70’s, and peaked as a whole in the 2000’s. US carbon emissions per capita still greatly exceed those of other rich nations.

    It’s very much possible to have modern first world living standards, even with significant reductions in our resource use and net emissions. We just need to line up the incentives (aka pricing) with what is good for the Earth. And we’re already doing that in many of the heaviest polluting sectors.


  • We are producing enough food (and clothes, and appliances, etc., etc.) for 10 billion people, and the planet is burning. It is not sustainable long term.

    That’s not necessarily true. How much of our overall greenhouse emissions come from which sector?

    From this chart, decarbonizing electricity and transport will go a long, long way, and decarbonizing manufacturing and construction could also give some room to reduce overall emissions by more than the entire agricultural sector produces.

    And it’s not just some kind of pipe dream. We’re doing real work at decarbonizing electricity, heat, transport, shipping, construction, etc., as the prices of low or zero emissions options start to outcompete the higher emission options for many applications.

    Plus if the data center boom crashes as a bubble, a lot of the infrastructure investment into increasing energy production and distribution with both high carbon and low carbon sources will at least have financed a lot of low carbon energy and the potential for curtailing the least carbon efficient generation methods.


  • This is actually one of the principles that is causing building codes to start accommodating load bearing timber in tall buildings. Even though wood is combustible, wood beams that are thick enough can withstand fire for long periods of time. They’re still working out what the different tests and standards should be, but some jurisdictions have approved timber skyscrapers.



  • sparkyshocks@lemmy.ziptoScience Memes@mander.xyzEvolution
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    2 months ago

    We should always look to nature, yes. A lot of aerodynamic designs seem to look a lot like the world’s fastest birds. Trees really do seem to optimize for capturing solar energy in an easily encoded blueprint.

    But also there are a few areas where we should recognize the limits of scope of the solutions nature has provided, or recognize the path dependency in how evolution might optimize for a particular pathway that no longer should continue to pose a restriction (the giraffe’s recurrent laryngeal nerve, for example).

    We’re allowed to mix and match. Just gotta be careful and recognize just how powerful billions of years of evolution is, as an optimization method.