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I thought it was standard practice to pull fuses on either side of your work area... if not, why? It's a quick task to pop one of them out of their clamps with those long fiberglass fuse pullers.

In this case, available current doesn't really come into play.

The human body has a resistance of about 10K Ohms. From Ohm's Law, at 110V, your body will only conduct 110V / 10K = 0.011A. This is less than 1/100th of the current available from the voltage source, regardless of whether it's from the outlet or the battery bank.

Put another way, either of these hazards has many times the amount of current needed to kill you.

Somebody a few comments back mentioned something on the order of 500A.

I just happen to have my 2005 NEC in front of me. Article 310, Conductors for General Wiring, has several tables that are of interest. Allowing for only 60 degree C operation (don't want to burn the people moving these cables :), we'd need a copper wire of at least 500 kcmil to handle the current (Table 310.17, Allowable Ampacities of Single-Insulated Conductors rated 0 Through 2000 Volts in Free Air Based On Ambient Air Temperatures of 30 degrees C).

That's a very big cable, about an inch in diameter and about a pound and a half per foot (That's for THHN wire). Remember, you'd need TWO of them in the hookup to complete the circuit.

Another problem would be ensuring proper terminations. That kind of power transfer does not work with poor terminations. The wires would have to be carefully bonded to the car, or the ohmic losses would destroy the terminals or even cause an explosion.

1 horsepower ~= 746W.

The horsepower of our computers has gone from figurative to literal.

One rack of these could theoretically consume more power than this: http://www.motortrend.com/roadtests/coupe/112_0107 _2000_mini_cooper_sport/

Will noone think of the salmon? http://riversideca.apogee.net/foe/fgphe.asp

As stated in comments to other replies to this message, ground source heat pumps work fine even into the far north. Even air-source heat pumps (with appropriate auxilliaries) are efficient into the northern tier of states. And natural gas is no longer cheap.

Geothermal cost comparisons: http://tristate.apogee.net/geo/minneap.asp
(NOTE: those are based on 6/ kWh; 60/ ccf gas; $1.00/gal oil). In most places, it's 8-10 cents/kWh, well over $1/ccf, and $1/gal oil? Ha! Try $2-2.50 at least. Even at the prices they list, in MN (not exactly a warm place), air-source is on a par with oil and better than propane, though behind natural gas. Ground-source beats them all be a significant margin; if you update the figures for current fuel/electric prices, even air-source heatpumps probably beat natural gas, and ground source beats oil by a 2x factor (circa $1000-1500/year), and beats natural gas probably by at least $500-800, maybe more.

A good energy costs calculator (for relative costs):
http://www.hearth.com/articles/47_0_1_0_M7.html. Note: for heat pumps, use electric and put in an efficiency value of around 250. That will be a pessimistic guess for year-round efficiency unless you live very far north; year-round average is probably more like 275, perhaps 300 in middle to southern states. Ground-source heatpumps - use a value of 350 to 400. And don't forget to update the local costs of different fuels and efficiencies for furnaces!

Actually, it's almost 20 degrees F higher than high-temperature, short-time "flash" pasteurization, and more than 30 degrees F higher than normal pasteurization. More info can be found here