this post was submitted on 15 Aug 2023
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[–] 18107@aussie.zone 12 points 1 year ago* (last edited 1 year ago)

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.