DC solar water heater viable?
I live in a state that makes it very hard to grid tie to utilities. On a duplex I own it has two 50 gallon electric water heaters. One for each side. My thought is to offset the over $1000 a year that it cost the renters. Its in a zone 6 so a normal solar water heater wouldn’t work. Gas and renters do not mix so gas solutions are out of the question. The heat pump water heaters don’t have enough space to operate, make noise and more likely to break down.
That leaves DC water heating with PV Panels. The thought is to place a 50 gallon water heater before the other two electric water heaters. A DC heating element 1kw at 144 volt range in that water heater. Run wire directly to around 1 kw solar panels. I figure that this set up would get around 8 degree rise at full power at 1kw per hour. Not exact science or figures. The cost per watt on the solar panels is less than a dollar. So a 1 kw setup should be around $1700 material cost.
Is this set up a dream or is it a possiblity? The cost of the controller, inverter, batteries are taken out of the equation. The heating element can take high voltage as long as the wattage isn’t exceeded. The DC wire would be under 9 amps because of the high voltage. Can increase to a 2kw system later on by just adding panels.
Just a thought as PV panels are becoming cheaper and gridtie isn’t an option.
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