Yes, they do make electric tankless water heaters. You can find some at the link below. Contrary to wild claims, In a standard home usage, there is almost no energy savings with an electric tankless heater. There is about a 25-30 % savings with a gas tankless heater. There might be more of a savings with an electric tankless in your application since hot water isn't being used often. Electric tankless, like electric tank heaters, don't require venting. There is a serious drawback with electric tankless in that they draw very large amounts of current and produce relatively small flow rates (measured in gallons per minute) If I remember right, a tankless electric unit that produces about 3gpm will pull about 100 amps. (the gpm will depend on your water temp going into the heater). Three GPM is a shower or would fill the washing machine slower than normal (washing machines are about 4gpm) If you don't have an extra 100 amp capacity to the barn, I wouldn't go with an electric tankless. I would go with a very well insulated electric tank unit. Pick up a unit with 2" of foam insulation and add a water heater blanket to it. Here is a link that might be useful: Electric tankless

I can remember back in the late 50s and early 60Âs when fuel was cheap the water heaters were operated at 180degF and they had no insulation or external jacketing. In those days there was a great concern that people were accidentally bumping up against the water heaters and receiving severe burns. The standards were then amended requiring that all water heaters must have a minimum of ¾" of fiberglass insulation, a sheet metal jacket and under no circumstance could the external temperature of the unit exceed 140degF under normal operation. During the first fuel crisis in the mid 70Âs people were encouraged to install additional insulation blankets to reduce the standby losses from the water heater, however it was soon realized that if an insulation blanket is improperly installed it interferes with the normal function of the water heater thermostats and temperature & pressure relief valves causing very erratic temperatures and in some instances creating safety issues. In addition, quite often when the insulation blankets are improperly installed they interfere with the normal flow of combustion air and result in very high levels of carbon monoxide. In the late 80Âs the plumbing codes were again amended requiring that ALL water heaters must now have a minimum of R-12 insulation. REF: International Residential Code IRC-504.2.1(en) Uniform Plumbing Code UPC-150(j)1A(c ) The codes specifically sayÂ"No external blankets required" Many local codes have amended that wording to say "External Blankets Prohibited". In my jurisdiction there is a $50 fine for even selling a water heater blanket. In order to meet the new insulation standards most water heater manufacturers have discontinued the use of fiberglass insulation and they now use cast in foam insulations, which often far exceed the required R-12 minimum Everyone seems to be fixated on the supposed high energy wasted to standby losses from a tank type water heater, but in reality such is not the case. Two years ago our plumbing apprenticeship class, in co-operation with the local gas company and a number of local hardware stores, appliance dealers and plumbing suppliers set up a project to test the actual cost of water heater standby losses. Twelve different makes and models of residential contractor grade 50gal gas tank type water heaters were installed in an unheated warehouse. All 12 units were fed from a common water line and each water heater is supplied through a separate gas meter. Each water heater is then fitted with one line on the output side that terminates into a keyless hose bib beside the unit, thus there is no demand from these water heaters therefore they represent standby losses only. The water heaters were then filled and left standing with the thermostats set at the code maximum of 120degF. Every month the gas meters are read and the fuel cost is computed at the standard residential rate for this area. After two years of following this project it has been determined that the monthly average standby loss is $5.02. (The worst case in the test is averaging $5.87mo.) I might add that two of the water heaters in this test have specific wording in their installation manuals that states the addition of an insulation blanket will void the warranty.

Are you thinking of having the foil tight against the surface of the heater, or of leaving some space between - maybe a half inch? I think that they say that if there's an inch or more of space in a window, that convection will take place between the cold and hot surfaces. If so, what would one use as spacers between the tank and the foil wrapper, to keep the small interval constant? Also, the foil wouldn't be the only cost ... ... another use for duct tape! If you use masking tape or clear tape, it'll deteriorate after three or four years and need to be replaced. How be you use some of the foil to make a medal for yourself, labelling it, "Shining example of energy conservation"? You could even make a large one, with a mirror in the middle, with a small hatch covering it, which you could open using air through a tube from a bulb in your pocket, that you could squeeze when you meet someone who's a good example of an energy conserver, especially an innovative one. You could even carry a camera to take a picture of the smile on their face when they saw their face in the mirror. Of course ... then they'd want such a medal, as well, no? The sale of such should finance the foil (plus duct tape) for your water heater. Or your share of a generator's purchase to service half a dozen houses' freezers, fridges, etc. in case of power outage. Maybe even a furnace ... if local code will allow you to install a push 'n twist plug in the line to your furnace. Dang! You pinch my insulation ... it's up to the landlord to replace it ... ... but the guy that hurts is I ... cause I have to pay for the oil! Landlord's worried about a couple of evergreens whose branches are nearing the power line (one touching). So ... he girdled the tree, about 8' from the top, figures the branches'll die, maybe even the wind knock the top off, eventually. He's a sod farmer, chairman of local conservation authourity. It seems to me that we need to get serious about energy conservation ... not only due to the need to conserve it, but for warming and polluting reasons, as well. If we think that we've had trouble thus far with regard to all three of those problems ... just wait till Asia and South America get into high gear! Enjoy spring. ole joyful

I was just reading an interesting site about a guy who was heating his water for two people using ONLY the pilot light. In theory it should work. I would think if you put a blanket, or maybe two on the heater, insulated the pipes and the like it could really work. I don't doubt that the guy does it. And when you consider how much heat is given off and usually wasted by a pilot light, it's something to consider. The poster has his gas water heater set up so that the main burner cannot come on. In his case, the pilot light alone heats all of the water needed by 2 people. He goes a step further, and does not vent the hot water tank to the outside, and actually restricts the water heater flue passage so that less heat is lost by convection through the flue opening. The justification for doing this is that the pilot light alone is no larger than the pilot light on a stove or gas refrigerator, and these are safely run without and outside vent. While I don't see anything wrong with this logic, I'm not sure I would go this far, as it seems to be getting a bit close to the boundaries of safety. But, it is amazing to me that a standing pilot light can supply this much hot water -- it gives some feel for how much energy a pilot light wastes. (snip) How much water should you be able to heat with just a pilot light? If you take 6 therms per month as the an average pilot light energy use: Energy per day = (6 therms/mo)(100,000 BTU/therm)(1 mo/30 days) = 20,000 BTU/day 20,000 BTU per day is enough to heat about 30 gallons of water from 50F to 110F assuming 75% efficiency ** ** The Calculation: If the water needs to be heated from 50F to 110F, then 20,000 BTU would heat: Water per day = (20000 BTU)(1/(110F-50F) (1 /1 BTU/lb-F) (1 gal/8.3lb) = 40 gals per day at 100% efic If the efficiency were 75%, it would heat about 30 gallons per day. Here is a link that might be useful: A Pilot Light Water Heating Strategy