How about using a MotoMaster Eliminator emergency car starter with a timer? Run an extension cord fromthe EBH into the cabin ,plug into a timer that is connected to the Motomaster . Recharge the Motomaster at home or by sloar panel. To get a decent solar panel to run the EBH would be approximately $1/watt(unless you DIY) A MotoMaster starter shouldn't cost much over $80-90 to get the whole enchilada (MM ,ext cord & timer) .

I thought about a good deep-cycle battery. If I have done the calculations right, it would take a battery rated at 100ah or more to run the EBH for 3 hours.(400W/12V=33.3amps/hour) Does this sound right? I would have to figure in what it would take to run an inverter so 110-120ah battery might be better?

Yeah I think that figure is correct . I double checked against this. It figures 115 aH including invertor/batt loss. Costco has them for about $60 and invertors @ $30.

Excuse my ignorance, but what is P&G and EBH?
Gary

P&G= Pulse and glide. Pulse to a higher speed target and glide to a lower speed target and repeat. In the Prius, the glide portion is usually engine-off. EBH= Engine block heater.

Thanks, P&G would be difficult to do in heavy traffic.
Is that how much people are getting their extraordinary high mileage? Using
P&G?
Hmm...

GS is the acronym capital of the internet. Ahem, Gassavers even.

Actually, this can be a great place to do it because your pulse is so slight and your glide lasts a long time. Like in traffic at 5-10mph, just leave it in neutral... when you get going so slow that the guy behind you is gesturing or honking, then put in gear, pulse for about 2 seconds up to 3 or 5mph faster than traffic so to close the gap and then pop back into neutral etc. If you time it right, you won't hit the guy in front of you before the glide slows you down. Timing is everything in hypermiling in traffic... but if you get good at it you can get awesome mileage around town or in heavy traffic. Sometimes I get excellent gas mileage in town because everyone where I live drives so slow, and if I get all the green lights (I live in a small town, with only a few lights) then I can just doddle through town at 20mph in neutral - then pulse to 30 and glide for another half minute or so in neutral and Bob's my uncle.

Of course, if you live in a hilly town, then forget it. Nothing you will do at 10mph on a hill is going to net you anything but disastrous figures. One guy selling his VX who lived in SF said his VX got "30+mpg!" I found this so laughable I had to email him asking how he managed to get such horrendous mileage in that car -- that sure is a feat! He replied: "Have you ever been to San Francisco?" I then realized that the hills were killing his FE.

Yeah, the hills would kill the FE because as soon as you start coasting back down you have to hit the brakes for safety resons and so kill the speed that you develop.

If driving in an area where you can coast back downhill without braking, the penalty for hill climbs is reduced considerably. There's probably still a penalty - that is, some of the 'stored energy" you build up when climbing is never recovered as motion - but it wouldn't be a total loss.

I think moderate hills may be the best for fuel economy. Hills that will coast you at about 45mph. Better than flat.
I was thinking about it today and I finally figured out the reason.

https://bp0.blogger.com/_Y8WoJeZ-J4c/...00/Hill+FE.jpg

Okay, imagine a car at the top of the hill on the left side of the image. Now you are the driver, and you throw it into neutral to coast down the hill. You coast all the way to the beginning of the bottom of the other hill and put it in gear and climb to the top. Right near the top, you pop it back into neutral just at the precise point so that you coast and come to a stop at the top of the hill. You then turn around and do the same thing going the other way.

Ask yourself. What percentage of the time were you in gear? Only when climbing the hills. What percentage of the distance traveled in both directions makes up the hill? And what was your mpg while climbing the hill? What is your mpg while maintaining steady state 45mph on flat? Would be a fun research project for a student like myself.