Electric thermal storage systems (ETS) are so common in the U.S. that you hardly ever see anything written about them. Only when a University decides to heat water (for showers in dorms)solely with a dedicated megawatt wind machine or such, do you even see it being news worthy.
Many private (co-ops) will cut your rates with a separate meter if one or more ETS units are installed in your residence, but it usually requires a separate meter (usually free). They can then turn on or off power to them as they wish to cut peak power demand. I have a unit installed on my domestic waterheater, voluntarily allowing my power co-op to shave some peak demand load(no second meter). I still have plenty of saved hot water until they turn the unit on.
Private Electric companies may give similar off peak rates to ETS systems, and Federal incentives may be available. They MAY(read in probably will) charge for a second meter though. There are off the shelf units for home use in the 2 up to the 6 Kw range, and I'm quite sure much higher if you are on the grid.
As this was posted in the wind section, quite a few people on this board dump extra power after their battery banks are full into a spare water heater making it a preheater. Others dump extra electrical power directly (air resistance heater) into the house or a power shed. This could be put to use at a later time if the air units were placed in an insullated box containing ballast rocks, cement slabs of the proper thickness or other....
Don't know if any of this helps, hopefully someone can provide a link to what you are looking for. The size unit(s) and such would be helpfull, and perhaps the intended use(home or office, or other? Doubtfull if this is worth 2 cents, just a quick primer.... Gary D.
