4 ms·

I'm curious how they perform in cold conditions. Where I grew up, a solid 50% of the school year was at or below freezing regularly. We really worked those bus

I'm curious how they perform in cold conditions. Where I grew up, a solid 50% of the school year was at or below freezing regularly. We really worked those bus heaters -- you know the type, under a few seats scattered around the bus. Curiously, it doesn't seem that buses use heat from the engine, like most ICE vehicles, for heat. Instead, I'm pretty sure they were just using power from the motor for electric heating elements with fans. Given that an electric bus could easily fit an enormous battery slab under the seating, I wonder if electric buses could be even better than ICE buses in cold conditions -- barring the obvious issues with battery efficiency in cold.

Mountain_Skies 5y ago
Wonder if radiant floor heating would be a good solution. Adding a warm air blower near the front to counteract cold air intrusion from opening and closing the door could help keep the interior of the bus a nice constant temperature.
- mjevans 5y ago
  Single pane (if thick) windows, very loosely sealing; in recent years possibly open for fresh air even in cold months. I grew up in a semi-temperate region that only had at most maybe a month of really cold temperatures each year. Those under-seat heaters were still very nice to be near and also helped to melt the snow and slush into just ice on the floor. You should assume, from a heating and ventilation perspective, that the inside of a school bus is a mobile open air tent, but simultaneously also on the verge of being an enclosed space packed to the gills with people.
elihu 5y ago
LFP batteries don't handle below-freezing temperatures very well, but that could be mitigated by using insulation and water cooling/heating depending on the time of year. Also maybe hooking them up to a pre-heater system that gets the batteries up to temperature before their route begins. (Sort of like those oil pan heaters they use in really cold climates.) Cabin heating could be done with a heat pump for more efficiency, I suppose. Heating could consume quite a bit of power, but I suppose compared to the energy required to move a school bus around it's probably fairly minor.

Mountain_Skies 5y ago

Wonder if radiant floor heating would be a good solution. Adding a warm air blower near the front to counteract cold air intrusion from opening and closing the door could help keep the interior of the bus a nice constant temperature.

mjevans 5y ago
Single pane (if thick) windows, very loosely sealing; in recent years possibly open for fresh air even in cold months. I grew up in a semi-temperate region that only had at most maybe a month of really cold temperatures each year. Those under-seat heaters were still very nice to be near and also helped to melt the snow and slush into just ice on the floor. You should assume, from a heating and ventilation perspective, that the inside of a school bus is a mobile open air tent, but simultaneously also on the verge of being an enclosed space packed to the gills with people.

elihu 5y ago

LFP batteries don't handle below-freezing temperatures very well, but that could be mitigated by using insulation and water cooling/heating depending on the time of year. Also maybe hooking them up to a pre-heater system that gets the batteries up to temperature before their route begins. (Sort of like those oil pan heaters they use in really cold climates.) Cabin heating could be done with a heat pump for more efficiency, I suppose. Heating could consume quite a bit of power, but I suppose compared to the energy required to move a school bus around it's probably fairly minor.