Tank water heater 240v AC

[jpbrooks1979]

Ok heres the plan. I have a apt in the backyard running 1000w on roof installed in series. 10 100 watt panel. Producing 230v victron charge controller 250/70 pared with a renogy 2000w inverter. Yea that needs a upgrade. 4 300ah 12.8v lithium powerqueen batteries in parallel. That seems to be enough for the apt. Next step is a question. I want to put 11 100w panels on the roof. Again in series. Yielding 240v Dc. Run that through a 5000w inverter. Do not install batteries. Hookup a 240v tank water heater. Of course it will only heat up in the day. The thermostat will keep the 40 to 60 gallons at a certain Fahrenheit. The questions i have. Will the low current damage the water heater? And second will this work

 

[Offgrid Jungle]

Buy a solar hot water heater and put it on the roof. Done. Skip all the stuff you are planning to buy and just covert the sun directly to hot water.

 

[jpbrooks1979]

The weight would be a factor. Panels are a investment. The inverter is the only real cost. The current is determined by the voltage and resistance. Have you priced the 60 gallon all in one water heater? Its about 5 times the cost if panels inverter and water heater

 

[efficientPV]

Use something like this https://tolnix.com/mppt-pwm-solar-water-heater-controller/

 

[JonathanW]

Idk about the ac thermostat rated for dc. Especially at that voltage. I really dont know. I think I have read concern about it else ware. I thought about the same idea but figured all solar into ac was more efficient as a whole system.

 

[robbob2112]

seems like the simplest answer would be to have the panels tied directly through a DC contactor to a heating element in the water heater....

A simple thermostat with AC power to control the contactor.... Or run a small battery with DC current to control the contactor -

Get one of the battery hookup contactors for $15 ... EV pulls - so they are meant for many thousand make/break cycles under load - and with low voltage/low current they will last forever. They come DC powered with and economizer on the coil so the waste energy is minimal. If you need to feed it from higher voltage AC you would need a stepdown transformer, a pair of diodes and a capacitor to trigger it. i.e. half wave rectifier and a cap to smooth it a bit... or get a full wave rectifier - they are cheap and the current flow for this application is minimal.

 

[S Davis]

Hiccup

 

[robbob2112]

Hiccup

huh? Have a bit to much to drink there? Don't drive.... and if you are home, have another.

TE Connectivity EV200AAANA 500a 0-900vdc Tyco 12/24v

These were recovered from EV battery modules. These are VERY EXPENSIVE online. If you have any project that needs a high current relay this is your chance to save some money. Make a cheap 30a BMS into a 500a BMS. This will work for batteries in the 9-36v range so perfect for Lifepo4 and Lithium...

batteryhookup.com

 

[134434]

Other than the expense, why resistive hot water? Heat Pump/Hybrid water heaters have come miles recently and will give you 3-4x the amount of hot water than resistive out of the same amount of power. Personally I would rather build up my main system and have 120/240 split phase than have a dedicated system just for water that I couldn't do anything else with.

 

[Daddy Tanuki]

huh? Have a bit to much to drink there? Don't drive.... and if you are home, have another.

TE Connectivity EV200AAANA 500a 0-900vdc Tyco 12/24v

These were recovered from EV battery modules. These are VERY EXPENSIVE online. If you have any project that needs a high current relay this is your chance to save some money. Make a cheap 30a BMS into a 500a BMS. This will work for batteries in the 9-36v range so perfect for Lifepo4 and Lithium...

batteryhookup.com

those are a great value, i bought several of them to play with for my water boiler project... waiting for winter to finish so I can get back to it... working under the house for the water lines in this weather is a solid no go.