Quote:
Originally Posted by gpsman1
Your HV battery only has 400 watt hours of usable power.
Battery power is the issue here.
Tail-lamps / brake lamps / turn lamps are about 25w each.
Tail lamps are always on, and brake lamps would depend on if you are in stop & go or Highway.
So you have a 50 w constant draw for tail lamps, and 100w intermittant every time you hit the brake. Let's assume an average of 60w draw over an hour.
60 watt hours is 15% of your HV battery, so not insignificant, especially added up over years. Electrical draw at night = about 2 MPG loss. I am reducing that by 15%.
-John |
Your analysis is valid but only if you are on EV all the time... Its a percentage thing... the motor is going to drain your battery in a few minutes not hours and then the engine will kick on and recharge the battery anyway.... the VAST majority of the energy lost during that discharge cycle will be from the motor draw not the lights. And when the engine is ON (which most of the time it will be) it doesn't matter how big the battery is, it only matters how much 60W is compared to the total energy being produced by the ICE both to drive the vehicle and to recharge the battery.
ULTIMATELY since all the energy is developed from the ICE, the real measure of the MPG savings doesn't involve the battery. Its how much energy does the engine produce and how much is used to propel the vehicle vs how much the lamp consumes... My guess is you won't even notice the difference... you might be able to measure the tiny loss from the headlamps on high beam but the energy used to drive ~3700lbs through the air at speed must dwarf 60W.