Efficient? 1,000 watts produces 3,412 Btu. 1,500 watts = 5,112. At 12
volts, you need 125 amps assuming 100% efficiency. You only have a 90
amp alternator and at least 30 is needed to run the engine and charge
the battery. The stock heater can probably produce 12,000 btu or more.
You will need a lot of battery capacity to run this set up. At least two
golf cart batteries. If you really need heat, you need some type of
furnace.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of rockin' robyn
Sent: Friday, April 22, 2005 9:34 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: CDN Tire Inverter questions

I don't know much about this stuff either.  I was thinking of getting
an inverter so that I could power up a space heater for those cold
off-season mornings & evenings.  The heater that I have is 1500W.  Does
that mean I'd need to get a 1500W inverter?  I wouldn't be using it
without the van running, but it would be more efficient than the van's
heater which can take so long to heat the space up.

Any advice would be appreciated.

Thanks,
-Robyn.