[stevehull]

phreich,

Not AC, but have some thoughts.

The best way to look at your costs is to look at what it costs to provide a BTU of heat or cooling. There are a number of spreadsheets on the web that do this.

You type in what the costs are per them (natural gas), gallon (fuel oil), electricity (resistance heating or heat pump) etc.

Then you put in the efficiency of the unit. For combustion fuels, this can range from ~ 80-95%. For resistance electricity the value is 1.0 (or 100% depending on the spreadsheet).

For a heat pump with a COP of 4, you put in 4.0 (or 400).

For cooling you out in the SEER of the cooling unit. Most geothermal heat pumps have a COP of 3-5 and a SEER of 25-45.

Bottom line. Even with commercial prices for GT heat pumps, they pay off quickly compared to natural gas - even here in Oklahoma.

You can "play" with future costs to see what happens if natural gas goes up as you suggest.

I would be aware that more and more natural gas is being discovered as more oil is found. A case can be made that it will be many, many years before natural gas doubles/triples in price.

The big gorilla is transporting this fuel to Europe and the far east. It will take some really new and novel ways to compress and refrigerate the gas for shipping out of the continental USA.


Steve