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Eric's avatar

Supposedly, the government of Ohio has provided up to $2Billion in tax incentives for Intel to build the manufacturing in Ohio. The largest ever incentive package for Ohio.

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Brent's avatar

Re Efficiency of Electric Vehicles. I suspect the author was trying to find a nice way to make an apples to apples comparison of the relatively small sample of EVs currently available for sale. While the chart looks very presentable, I don't believe it offers any valid conclusions for a couple of reasons:

1) At steady state highway velocity the energy consumption is dominated by aerodynamic drag, where drag = 0.5*density*(velocity squared)*(drag coefficient)*(Frontal Area). The drag coefficient of a sedan and a pickup are drastically different as are the frontal area. This is why you wouldn't compare an ICE sedan to an ICE pickup truck, same logic applies to EVs.

2) In the city the mass of a vehicle has historically been a large driver of its fuel efficiency. This is because the energy required to accelerate the car is = 0.5*mass*(velocity squared). In the city a vehicle is repeatedly accelerated and then brought to rest because of stop signs, stop lights and traffic. Every time an ICE vehicle is brought to rest all of the kinetic energy is turned to heat as the brake pads rub on the brake disc. This heat is unrecoverable and wasted to the atmosphere. EVs employ regenerative braking where the wheel motors are used to slow the vehicle while subsequently charging the battery. While this process isn't 100% efficient, much of the energy is recovered making the mass of a vehicle much less of the variable driving in city energy use.

In summary, 1) on the highway aerodynamic drag is the driver of energy use, not mass. We can't compare cars and trucks (even if they are EVs) unless we attempt to normalize for drag coefficient and frontal area. 2) If a vehicle employs regenerative braking (as EVs do), the mass of the vehicle is less of a factor for in city energy consumption when compared to a traditional ICE vehicles.

While the chart is pleasing to the eye, I don't believe it offers any meaningful insight. Cars need to be compared to cars and trucks to trucks. Normalizing for mass is not a meaningful way to make the data comparable.

*I am not an expert at anything. I'm open to being wrong.

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