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A common design in my area is a heat exchange tank upstream of a traditional gas or electric water heater. They use ethylene glycol (antifreeze) that circulates by thermosiphon action from a solar panel to the tank. The illustration below shows a more complicated (with pump and controller) version. So, you heat a tank of water with a coil full of antifreeze ...


4

I have about 50 55-gallon drums stacked in my basement, all filled with water. They are stacked one on top of the other (bottom row/top row) along our north basement wall. I have two in floor-mounted fans, one pushing, one pulling, mounted in the ground-floor joist cavity (from above they just look like floor mounted cold air returns). During the day, the ...


3

For me with a solar system in New Zealand, we've found the following quite effective: we've got a solar tank with 2 electrical elements in it, one at the bottom of the tank, plus another one about a third of the way down from the top. We run the bottom element overnight intermittently during the winter months when the whole tank is cool, the forecast is ...


2

Yes, of course. There are a huge number of well-tested DIY projects you can find here: http://www.builditsolar.com/Projects/WaterHeating/water_heating.htm I would heavily recommend browsing that site and learning from the experience of others who have already done what you're interested in doing so you don't burn even more money.


1

This article provides excellent information about maximizing thermal mass: Phase Change Materials (PCMs): There is growing interest in the use of PCMs as a lightweight thermal mass substitute in construction. All materials require a large energy input to change state (i.e. from a solid to a liquid or a liquid to a gas). This energy does not change ...


1

One boringly unexciting approach is double drywall (and don't choose the lightweight type) though that is more often done when building or rebuilding/remodeling than as a retrofit without some other rebuilding/remodeling going on. It easily and unobtrusively adds a significant mass to the interior structure. Bang for the buck, and in most cases pound for ...


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I don't think a plain resistor is what you want, I think a resistive load is what you want. Incandescent bulbs as mentioned would work and they're easy to find and work with. Of course you won't want an inverter in this setup, and 12V bulbs are readily available for automotive applications. But it isn't necessary to reinvent the heater, there are tons ...


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The short answer is that electricity is not a particularly cost-effective way of generating heat, and solar panels are not a particularly cost-effective way of generating electricity, so this is not really a smart financial decision. If you are trying to generate heat from the sun you are much better off getting solar thermal panels. A PV panel only gets ...


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Works (while the sun is shining), but is a very expensive option and not overly efficient. Solar PV panels of a remotely affordable price are about 10% efficient in terms of converting sunlight to electricity. Most of the rest of the sun's energy that hits them is converted to heat. So, from a sun conversion point of view, direct solar thermal collection ...


1

Gosh - a buck a therm is "expensive gas rates" - if I could get it (I can't and never expect to) it's more like a buck and a half...year round. So, you're using 1 million to 1.3 million BTUs/day - if you could manage storage swing of 50 degrees F (not unreasonable with radiant floor, a low-temperature emitter) that might be 3250 gallons of water (at a round ...


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It would almost undoubtedly be a better use of your available money, time, and space to add insulation, not a complicated solar heat storage system, which after all, will do nothing for you half the year. Start with your basement and insulate the walls and the rim joists. Then move to your attic and air seal the floor and add about 12-16 inches of cellulose ...


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Are the PEX hoses black and is the sun side of the re-purposed aluminum plates black? If not you may want to consider changing this so as to increase the efficiency solar energy absorption.



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