12v Vs 110v Question For A Mattress Pad Heater

For me, electricity seems a mysterious thing. Having spent the last several days at Acadia Nat'l Park on the Maine coast, ill-prepared as it turns out and mostly freezing, I am thinking about purchasing something to use briefly to warm the sleeping bag before getting in. Is it more efficient to purchase a 12 volt version that can be used only in a vehicle or, now that I have a wonderful inverter installed in the camper, am I better off buying a 110-120 volt model that I could in the house as well? My plan is not to fall asleep with it running, but rather to make the leap into the sleeping bag less abhorrent. It's not fun jumping into an icy lake which is how it feels now.

 

I would think if in both cases the power is 12v you would be better off getting a 12v blanket. The inverter uses power to do its job and that is lost power. The lost power is in the form of heat so if the inverter is in the cabin you would also benefit from it to some degree (no pun intended).

 

The AC blanket through the inverter will use a tremendous amount more electricity than the 12v blanket. The most a 12v blanket will use is about 180 watts. The AC blanket will use 750-100watts of battery power. Then you add in the inefficiencies of a normal inverter. A normal inverter is only about 70% efficient (at best). That means you can tack on an extra 30 watts or so of inverter loss running the blanket. So, if you run an AC blanket off the inverter you would want to run it briefly to warm the bed and turn if off (all you would need most likely).

I would say I have to agree with Tour 931 as usual, the 12v blanket would probably make the most sense to me if camping off grid. I worked as an engineer at an inverter manufacturer for 13 years and can really attest to inverter inefficiencies.

Cary

 

Thank you! That is what I had thought intuitively, but my intuition has failed me often enough to seek the advice of someone who knows what's what instead of my just guessing.

 

Excellent ideas! And yes, it certainly does beat tenting. Being cold and wet in a tent was fine when I was younger, a whole lot younger, but I have quickly learned that being old and cold in the camper is lots more comfortable because of being dry. Hot water bottles are now on my list.

 

Here's the link to a popular 12-V bunk warmer: 12 Volts Bunk Warmers Archives - Electro Warmth

A bit pricey at over $100. Only 36" wide so we've got it pinned along the bottom of the mattress - they used to sell a queen-size once upon a time but last time I head, they had no plans to bring it back.

 

I bought one of these for myself. Lane won't have anything to do with them, but I found it works very well if I leave it on for an hour and switch it off just before I go to bed. A pleasant surprise is that it doesn't draw down the battery.