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Kerosene? Maybe. A net-zero kerosene? No, because it's a made up stuff, like Toyota's self-charging ICE cars or "clean" coal, gas or whatever. BTW: Tesla just

by kjksf 4y ago

Kerosene? Maybe. A net-zero kerosene? No, because it's a made up stuff, like Toyota's self-charging ICE cars or "clean" coal, gas or whatever. BTW: Tesla just released a semi truck that does 500 miles fully loaded and it's a v1 technology. It's already good enough for most trucking and an EV semi 10 years from now will be both cheaper and longer range than that.

travisporter 4y ago
Well net zero fuels are a theoretical possibility, and it's a big startup scene. I'd wait for more Tesla semis on the road before agreeing with that SF to LA semi test. I think they can pull it off, but the economics should make sense.
- cduzz 4y ago
  The future's a big place; there are plenty of use cases for a truck where it's fine to have a 200-500 mile battery for hauling stuff on the last mile or between warehouses. There are plenty of other use cases where you need lots more energy density. It's silly to assume the same vehicle needs to be able to do either on alternating sundays. For trucking, at least, a modular approach seems reasonable where some are all electric and some are hybrid where you chose the maximum generator output based on your expected duty cycle. A truck to lug cement over the Rocky Mountains on a daily basis will have a different load curve from one hauling across Texas. Hybrid focused ICE engines will likely be quite different from those designed as the primary motivation for cars, and there are probably not many situations where a v8's the right size. (Hybrid where they only run a generator to charge a battery will likely be optimized for only a couple RPMs and loads intermittent operation, etc)
bcrl 4y ago
The big challenge for electrification is how to cope with energy demands of commercial vehicles. The Tesla semi needs 1MW for the fast charge. Yes -- that's 1000A at 1000VDC going into a single truck, which is a lot of power! Simultaneously charging multiple semis at a single truck stop means there needs to be many MW of capacity the electric grid has to deliver to that location. I can imagine that truck stops are going to need some form of local energy storage to smooth out the bursts on the grid for the trucks that need fast charging. Thankfully, a good portion of long haul trucks can use slower charging while the driver takes mandatory rest periods, so not all semis will need fast charging. To get a better idea of the scope of the problem: take a semi with a 300 gallon tank that takes roughly 5 minutes to fill at a fast 60 gal/minute pump. In those 5 minutes, roughly 12.2MWh of energy is delivered into the semi. In other words, one diesel fuel pump today can deliver close to 144MWh of energy in an hour (assuming 50% idle time per pump). Which means that to replace 6 diesel fuel pumps, you would need upwards 864 x 1MW fast charge stations. Even dividing the energy delivery rate by 10 still leaves you with an 86MW capacity requirement for a single truck stop. I think there's still a lot of work to be done before electrification of commercial vehicles on any large scale is viable.
- landemva 4y ago
  > truck stops are going to need some form of local energy storage to smooth out the bursts on the grid The truck stops will have a few tanks of off-road diesel to run a generator to create electricity to charge the truck batteries. Local energy storage for rural truck stops will be diesel in underground tanks, rather than diesel in truck tanks.

by kjksf 4y ago

travisporter 4y ago

Well net zero fuels are a theoretical possibility, and it's a big startup scene. I'd wait for more Tesla semis on the road before agreeing with that SF to LA semi test. I think they can pull it off, but the economics should make sense.

cduzz 4y ago
The future's a big place; there are plenty of use cases for a truck where it's fine to have a 200-500 mile battery for hauling stuff on the last mile or between warehouses. There are plenty of other use cases where you need lots more energy density. It's silly to assume the same vehicle needs to be able to do either on alternating sundays. For trucking, at least, a modular approach seems reasonable where some are all electric and some are hybrid where you chose the maximum generator output based on your expected duty cycle. A truck to lug cement over the Rocky Mountains on a daily basis will have a different load curve from one hauling across Texas. Hybrid focused ICE engines will likely be quite different from those designed as the primary motivation for cars, and there are probably not many situations where a v8's the right size. (Hybrid where they only run a generator to charge a battery will likely be optimized for only a couple RPMs and loads intermittent operation, etc)

bcrl 4y ago

The big challenge for electrification is how to cope with energy demands of commercial vehicles. The Tesla semi needs 1MW for the fast charge. Yes -- that's 1000A at 1000VDC going into a single truck, which is a lot of power! Simultaneously charging multiple semis at a single truck stop means there needs to be many MW of capacity the electric grid has to deliver to that location. I can imagine that truck stops are going to need some form of local energy storage to smooth out the bursts on the grid for the trucks that need fast charging. Thankfully, a good portion of long haul trucks can use slower charging while the driver takes mandatory rest periods, so not all semis will need fast charging. To get a better idea of the scope of the problem: take a semi with a 300 gallon tank that takes roughly 5 minutes to fill at a fast 60 gal/minute pump. In those 5 minutes, roughly 12.2MWh of energy is delivered into the semi. In other words, one diesel fuel pump today can deliver close to 144MWh of energy in an hour (assuming 50% idle time per pump). Which means that to replace 6 diesel fuel pumps, you would need upwards 864 x 1MW fast charge stations. Even dividing the energy delivery rate by 10 still leaves you with an 86MW capacity requirement for a single truck stop. I think there's still a lot of work to be done before electrification of commercial vehicles on any large scale is viable.

landemva 4y ago
> truck stops are going to need some form of local energy storage to smooth out the bursts on the grid The truck stops will have a few tanks of off-road diesel to run a generator to create electricity to charge the truck batteries. Local energy storage for rural truck stops will be diesel in underground tanks, rather than diesel in truck tanks.