4 ms·

> I was really waiting for the semi since the math didn't seem to work out. It actually does- they're going for long range which in the context of trucking is

> I was really waiting for the semi since the math didn't seem to work out. It actually does- they're going for long range which in the context of trucking is anywhere from 500-800 miles- surprisingly short compared to the 2500+ mile range of a fully gassed semi. Keep in mind that 500 miles is 8 full hours of 65 mph driving though! That covers 80%+ of all commercial driving. With an aerodynamic cab the drag coefficient of a semi can get to ~.4 with a 115 sqft frontal area. That works out to 132 kW at 70 mph. Including rolling resistance and 90% drivetrain efficiency that comes to 1,200-2,000 kWh for 500-800 miles. That's 5-10 tonnes of batteries at the module level (doesn't include cooling or armor). The engine, exhaust, transmission and fuel in a semi truck weighs several tonnes- at the lower end of range, converting to batteries could even reduce weight. Even 800 miles of range is a pretty insignificant increase to the weight of the tractor, especially if they can improve on aerodynamics or count range at a lower speed. The cost of all those batteries is 200-300k, which is expensive but not unusual for a semi truck. In short the numbers actually work out quite well for electric semis. Charging locations and power are an issue that will limit them to set routes for the near future, and even in the long term it will be hard to replace sleeper cabs doing 1200+ mile nonstop trips. However routes like that are very rare indeed.

SigmundA 9y ago
>Keep in mind that 500 miles is 8 full hours of 65 mph driving though! Truckers do 700 miles days legally. Your talking 10 hours to recharge on super charger for 500 miles of battery vs a few minutes at truck stop for diesel. Might be ok if they can sleep at super charger, going to be a while before that infrastructure is built out. simply not viable for long haul. >The engine, exhaust, transmission and fuel in a semi truck weighs several tonnes- at the lower end of range, converting to batteries could even reduce weight. A 15 liter diesel and transmission weighs 2 tons, 300 gallons diesel 1 ton. it will be heavier, meaning less capacity even with only 200-300 miles of range. >The cost of all those batteries is 200-300k, which is expensive but not unusual for a semi truck. The whole truck cost 200-300k, now you just doubled it.
- hwillis 9y ago
  I did mention that the trucks will be nonviable for any non-corporate use. I'll also point out that charge time is independent of battery size: as long as the charger is large enough (as in MW+), Tesla Semis will charge in the same time as Tesla sedans. So 200 miles in about 20 minutes. > A 15 liter diesel and transmission weighs 2 tons, 300 gallons diesel 1 ton. it will be heavier, meaning less capacity even with only 200-300 miles of range. Even with those numbers, that would only be a 5% increase in weight. It affects the capacity of fully loaded trucks (very minorly) but it doesn't affect the range whatsoever. > The whole truck cost 200-300k, now you just doubled it. Minus the cost of engine etc. Most nice trucks cost less than $200k so it is still easily double the average truck, but that's expected given maintenance and fuel savings. Upfront cost is comparable to some of the really nice European models.

SigmundA 9y ago

>Keep in mind that 500 miles is 8 full hours of 65 mph driving though! Truckers do 700 miles days legally. Your talking 10 hours to recharge on super charger for 500 miles of battery vs a few minutes at truck stop for diesel. Might be ok if they can sleep at super charger, going to be a while before that infrastructure is built out. simply not viable for long haul. >The engine, exhaust, transmission and fuel in a semi truck weighs several tonnes- at the lower end of range, converting to batteries could even reduce weight. A 15 liter diesel and transmission weighs 2 tons, 300 gallons diesel 1 ton. it will be heavier, meaning less capacity even with only 200-300 miles of range. >The cost of all those batteries is 200-300k, which is expensive but not unusual for a semi truck. The whole truck cost 200-300k, now you just doubled it.

hwillis 9y ago
I did mention that the trucks will be nonviable for any non-corporate use. I'll also point out that charge time is independent of battery size: as long as the charger is large enough (as in MW+), Tesla Semis will charge in the same time as Tesla sedans. So 200 miles in about 20 minutes. > A 15 liter diesel and transmission weighs 2 tons, 300 gallons diesel 1 ton. it will be heavier, meaning less capacity even with only 200-300 miles of range. Even with those numbers, that would only be a 5% increase in weight. It affects the capacity of fully loaded trucks (very minorly) but it doesn't affect the range whatsoever. > The whole truck cost 200-300k, now you just doubled it. Minus the cost of engine etc. Most nice trucks cost less than $200k so it is still easily double the average truck, but that's expected given maintenance and fuel savings. Upfront cost is comparable to some of the really nice European models.