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Sir I am broke
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this post was submitted on 15 Aug 2023
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I'd recommend an electric car for avoiding oil changes, but I think we still have a few more years until cheap second hand electric cars become available.
Answer: hydrogen
Hydrogen is only 30% efficient compared to 90-95% for batteries. Most hydrogen is currently made from fossil fuels, and contains less energy than the fossil fuels used to make it.
but an electric car is heavier than a hydrogen car, so the electric platform is less efficient. imagine carrying an extra ton of a batterypack wherever u go. hydrogen could be made from renewable energy, and doesn't require batteries to be stored. battery metals are finite. u can't scale that up. 5kg of H2 translates to 400km mileage.
Most large combustion SUVs are heavier than most electric cars.
Sodium ion batteries are being produced with no rare metals in them, and will be in production cars within a year. Hydrogen is difficult to store due to is low volumetric density, it's molecular size, and corrosive nature.
Hydrogen (fuel cell) cars all have a battery because a hydrogen fuel cell is slow to change it's energy output, so can't change its output fast enough to directly power the car.
Battery electric cars are about 90% efficient from charging from the grid to moving. Hydrogen cars are about 30% efficient from grid to moving when made from renewable energy. These efficiency numbers include the weight and rolling resistance of the car. The theoretical maximum efficiency of hydrogen storage allowed by the limits of physics is about 50%.
The volumetric density of hydrogen is so low that you would need 20 tanker trucks to transport the same amount of energy that 1 tanker truck of gasoline can carry. This is at maximum pressure or liquified.
Hydrogen only makes sense when the weight of the energy storage medium is critical. As demonstrated by American cars, it isn't.
I'd love to see the technology develop more but it's definitely not viable today. It's like when EVs started out.
Yes, but the difference is that it doesn't move at all, which major companies are really pushing that technology, there was a hype, but now it just sits
Toyota and some truck companies are the major ones pushing this