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The power density of gas turbine engines is way better than internal combustion. But we haven’t bothered with gas turbine cars and trucks because internal comb
by rgmerk 4y ago
The power density of gas turbine engines is way better than internal combustion.
But we haven’t bothered with gas turbine cars and trucks because internal combustion has good enough power density and other relevant advantages (better energy efficiency chief amongst them).
Batteries aren’t good enough for long-haul aircraft, long-haul shipping, small boats and a few other sundry applications, but they’re good enough for road transport.
- _hypx 4y agoA gas turbine is a really bad idea for a car. They take a long time to get up to speed and spew a lot of hot exhaust in the meanwhile. Gas turbine cars weren't practical cars at all. I will argue that the finite nature of battery related materials, plus their weight, is a major impediment against all-battery powered cars in road transport. They are not "good enough" except as a stopgap until the next idea comes around. Which ironically could just be synthetic fuels, but more likely something like a hydrogen fuel cell car.
- bryanlarsen 4y agoFuel cells require catalysts like platinum which are far less common than anything in a battery.
- _hypx 4y agoThey don't actually require platinum. Only some types. And even then, it is basically the catalytic converter in terms of platinum needed. It is also 100% recyclable already.
- bryanlarsen 4y agoAll catalysts are way less common than the Iron, Phosphate and Lithium in a mass market car battery.
- _hypx 4y agoNo, since sometimes it is also just iron or whatever. Not to mention that a catalyst is a surface, not a volume. You can get away with atom-thick layers of catalysts. Which is why even with platinum you only need a few grams of it. Cost of that is significantly less than a large mass of other materials.
- bryanlarsen 4y agoCatalysts are consumables and need to be replaced regularly. Battery materials are recyclable.
- _hypx 4y agoAgain no. Catalysts are endless recyclable.
- enslavedrobot 4y agoNickel iron oxide is the best catalyst for a type of fuel cell based on Anionic Exchange Membranes. Cheap as dirt and you only need milligrams per kW. But it's so cheap you can use a tenth of a gram just to be on the safe side.