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Old 07-19-2015, 02:53 AM   #6 (permalink)
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Originally Posted by thingstodo View Post
Based on 3800 lbs a decent conversion should get you 380 w-h per mile. A bad conversion maybe 450 w-h per mile. A Great conversion 350 w-h per mile. Do you run cargo or towing a lot? If not, I would not put the extra weight into your nominal calculations.

Thanks for the input. I think 4400lbs is about right for a typical loaded van with the expected added weight of the conversion factored in. I have a 1000lbs trailer that I tow quite often, but I plan on building a lighter 6-700lbs version soon. I could fit a generator to the trailer for occasional last resort use. The EV calculator predicted range doesn't change as much as I expected when I play with the curb weight. From 3800 to 5000lbs reduces range by 14 miles, which typically won't be the end of the world.

With low-speed driving and hyper-miling, running an AC system and using regen to stop at lights (when coasting in traffic just won't cut it) I'll bet you could beat 350 w-h per mile.
What's the most popular way to run the A/C? I think running it off the drive motor is out as I spend too much time stationary. I definitely like the idea of cooling off the interior before I get in it. Has the Prius A/C compressor been cracked?

If you have the room, centering the mass of the batteries at the centerline of the wheels is supposed to affect the handling of the vehicle the least. This is what I read of Teslas and such. I have no experience with having lots of room for batteries
It's front wheel drive, so I'll have to put a lot of batteries under the hood or it will just be forever spinning it's wheels (the rest will go under the floor as far forward as possible). It already has wheelspin issues I think an electric motor will be easier to modulate than a TDi in this regard. When I fitted a tuning box to add 50Nm it made it peaky and quite unpleasant in first and second.

That's an excellent question that I've never read before. There are a few things you use fuel for when stopped that electrics don't, like idling .. but there are things you get for free, like heat, that electric uses energy for. I would think there are too many variables to get a decent converted number.
I pretty much know I use 1l/100km idling. That figure is from an older van with an MPGuino that actually logged fuel used while stationary. I do pulse and glide (engine on in neutral) with the newer van so there's more fuel wasted idling while moving so as not to kill the turbo. I suppose if I really did EOC and idle stop at lights I might get my consumption as low as 6.5l/100km.

I'm surprised there isn't an established formula for converting fuel use to electron use. It would surely be more effective than using vehicle weight as the only input, ignoring aero drag and required speed.

If a heater wasn't a legal requirement, I would probably not bother fitting one.

Is it more common to run DCC converters or to retain separate 12V batteries? I'm thinking my 12V battery would be grid charged and sized to match my EV range, my 12V usage wouldn't affect my range that way. The roof has space for ~500W of solar panels which would probably be enough for my 12V requirements.

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