01-11-2009, 11:21 PM
space-time wrote:
GGD, when you go down-hill from your house, is the battery completely empty? If the battery is let's say 75% charged, then it will quickly charge to 100% before you reach the bottom of the hill and thus there is some energy that could have been stored but it's wasted since the battery is full. would be interesting to see what happens if you leave the house with the battery on a very low charge, let's say 10%, although I am not sure if the computer will ever leave it get that low.
It depends on which route I take, there are two ways down/up in different directions. One is steep and winding most of the way, the other is very steep near my house, and a more gradual slope with few turns the rest of the way.
When I drive home the first route, the gas engine needs to run most of the way due to the slope of the hills, so it's charging the battery as a side effect, so the battery will be about half full when we get home.
The second route is better, because electric can be used on the more gradual slope and drain down the battery instead of burning gas, and gas will get used just on that last very steep section (about 1/4 mile), and the battery will be much closer to empty when we get home.
I usually plan my errands so that I make a big circle, going down the first route, making stops along the relatively flat road in town that connects the two routes, and coming home on the second route, so that the battery will be as empty as possible for the next trip. I can get about 46 MPG for the trip that way.
Given my location, I'm not sure a plug-in hybrid will be much benefit unless the battery is a lot bigger, and there is a way to charge it to some fixed level that is below full, so that my trip down the hill can charge it the rest of the way.