My primary reason for looking into an electric furnace is a matter of comfort. Having only used electric heaters in the past for lead, moving to an electric furnace for aluminum seemed to be an easier step. I'm not set on using an electric furnace though.

One thing I have considered was operating the furnace in the comfort of my basement during the winter. Assuming this is safe to do with any type of aluminum furnace, using a gas powered furnace would probably need its own exhaust system. Opening the windows during the Minnesota winters isn't very practical. I do have a bath exhaust fan above my workbench, but it's meant for sucking out soldering fumes.

Another benefit of an electric furnace, specifically a 120v single phase, is it can be used just about anywhere. Work outside when the weather is nice, in the garage when its raining, and in the basement in the winter. I can bring it over to a friends house, plug it in, and we're in business. Right now, I'll need to do a little pipe work to add another gas appliance. Otherwise, I'll be swapping out the cloths dryer and furnace.

I understand your reasons for wanting to go with electric, but you have to consider what you're trying to do. It takes a furnace/melter that draws around 1000 watts to melt about a pound of lead, as I recall. (Somewhere, I have a 1# solder pot like that.) With the higher melting point of aluminum, and 10-20# charge, you'll need so many Btu's that you won't be able to do it on 120v single phase with supply conductors much under the size that serve your entire house, I don't think. It is much easier to get a lot of Btu's out of gas or solid fuel than it to get it from resistance elements. Just look at the size wiring it take to run your electric clothes dryer or stove (both of which probably take 220v anyway), for some idea of what you're up against.

For any kind of efficiency using electricity at all, you would need an induction melter. Again, that is going to want 220v at high current draw.

I've made small furnaces for melting 20# of bronze from nothing more elaborate than an old oil drum, some rammable refractory and a salvaged blower from a car heater, using propane for the fuel. The same can be done using fuel oil, coal, charcoal or even firewood. Yes, there are fumes to be dealt with. But, unless you're working in an inert atmosphere, you're going to have plenty of fumes from just melting that much aluminum, no matter how you do it.

I suggest you get some of the books available on the subject form authors such as C.W. Ammons, and Chastain. Do a search for "casting" and those names, you should find several titles available at places like Amazon or Abe Books.com.

You need serious knowledge to do such casting safely. Molten metal doesn't just raise blisters, it removes flesh and bone in an instant! Are you planning to put in a sand pit in your basement to do the melting/casting in? Do you have the required tongs, lifters, pouring shanks and cradles? Do you own asbestos spats, gloves and whatnot? How about the mixers and riddlers and rammers and copes and drags for the sand casting? You're looking at a fairly large and complex undertaking, and you need to study it thoroughly before you try it. Even then, you should really try it on a much smaller scale first, I believe.