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by mojomark 1268 days ago
The author of the article doesn't know what they're talking about. The issue in question is concerned with energy density, not break power of the motors. Electric motors are capable of delivering far greater torque than a similarly sized (weight/volume) diesel engine. Electric batteries on the other hand have far less energy desnity compared to an equivalent volume/mass of diesel fuel.
1 comments
tee_0 1268 days ago
It’s brake, not break. As in the amount of HP available at the brakes after all transmission/diff/etc losses are taken into account which doesn’t even really apply to electric vehicles.

They aren’t looking hard at all. If you just had a super capacitor bank to capture regen, all the energy from the stop and go could be retained and they could probably run the truck on the batteries that they are currently saying last only 4 hours.

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johnwalkr 1268 days ago
Brake horsepower is the power at the output of the engine. It's called that because it is measured with a brake dynamometer. Wheel horsepower or wheel brake horsepower (same thing) is measured after mechanical losses (at the wheels).

But "they aren't looking, why don't they just.." really rubs me the wrong way. Surely these people are experts in their own field and know what's available. After all, they are ordering trucks from a vendor, not designing trucks to their own unique requirements. Plus these Mack trucks indeed already have regenerative braking.

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mojomark 1262 days ago
Ha, yup, I used the wrong "brake". Silly me. The point is that power delivery and energy capacity of an energy conversion system are two different things and the author's incorrect usage of power to refer to energy is pretty egregious and is spreading an idea that is false - that electric motor vehicles deliver less power than combustion engine vehicles. That's my issue.

One only need look at the volumetric and mass energy density of diesel fuel and electric energy storage options to see that electric vehicles CURRENTLY store significantly less than diesel fuel tanks. That's well known and not a shock to anyone. Energy desnity of electric power storage (batteries, or even H2 fuel cells) will improve over time.

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