Hacker News Reader

Comment by simias | Hacker News Reader

You can do exactly the same back-of-the-envelope calculation for ICE engines as you did for the Tesla, you just need to know the average fuel consumption per mile and the energy density of gasoline. No need to worry about areodynamics.

View on HN

I was using that number to represent just the energy required to motivate the car, and assuming that an EV has near-perfect energy translation from battery to movement (and therefore providing an accurate enough representation of that energy). It gets a little complicated if you want to consider the fuel input, as you start getting into wells-to-wheels calculations. Depending on your power grid energy mix, it also makes things quite a bit worse for EVs.

Actually you already have something like this. MPGe is used across EV and ICE vehicles alike.

Fuel is far more energy dense for ICE engines are far far less efficient.

I don't get this comparison point as well, electronics is dwarfed compared to other far more energy intensive industries.

You can, but that wasn't the point I was making. My only point was that it takes around 300Wh/mile to move a car about the size and shape of a Tesla, regardless of how you power it. I won't use the example of Tesla next time, as it seems to confuse matters.

MPGe also touches on the source of the energy you are using to propel your car, and depending on your power grid energy mix, can produce quite widely different results for EVs. Once you also take into account transmission and conversion losses, it is not as good as you'd think.

Electronics is one of the most energy intensive industries in the world, especially if you do the calulcation per weight of final product.

Reply on news.ycombinator.com