A regular single bed electric blanket uses about 150 watts on high and about
50 on the lowest setting. Powered through an inverter you can expect to eat
5 to 6 amps/hour on low. .

You might want to look at a 12V electric truckers blanket
http://www.roadtrucker.com/12-volt-h...s-sheets-1.htm but they
are only 57" x 27". Set on high 4.2 amps/hour it would eat about 32 amp
hours a night. A fully charged group 27 will supply about 45 usable amp
hours to 50% so you will not be able to run much of anything else. A 58'x42
will eat 9 amps and pretty well drain a group 27.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"richard" wrote in message
oups.com...
I treid to post this earlier but do not think that it worked. forgive
me if it double post. Does anyone use electric blankets on board? I
find that at home I only use it on the lowest settings and do not heat
the rooms. How are they with battery power? I have a battery size 27,
and a 1750 Watt inverter. Would I be able to use it all night? How
about with shore power? Thanks