
Originally Posted by
vnx205
I realise that there are benefits in not having the engine running while the car is sitting still, but I have often wondered how significant the disadvantages are.
How long does it take for the power drained from the battery on each start to be replaced?
How much extra fuel is used because the alternator is working hard more often?
How likely is that that someone whose regular driving involves a lot of stop/start driving early in the trip before the engine warms up will have to replace the battery much sooner?
Has there been a significant increase in the number of drivers stranded at the traffic lights with a flat battery?
Perhaps all those things are so insignificant that they can be ignored, but I haven't seen them discussed elsewhere.
I have seen nothing on this either, but I suspect the problems are largely resolved by having an intelligent controller that does not switch the engine off until it is warm, nor if the battery voltage has not recovered.
The starting energy once warm, for a small modern engine, either petrol or diesel, will not be very great, as they will start, for a diesel, on the first compression, and for a petrol engine almost as fast. Particularly with the modern tendency to fit very large alternators because of high loads, recharging will be pretty quick. I would not be surprised if vehicles that have this feature use a larger battery, not so much for the starting, but for all the other junk that is draining the battery while the engine is stopped (computer, lights, entertainment system, seat heater, demisters, fans, window winders, door locks, security system, etc, etc!).
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
Bookmarks