So, back on 5/1 I wrote:
Coincidentally, last week I ordered
PWM MPPT Heater Charger Regulator Solar Photovoltaic Solar Panels Hot Water PV | eBay
PWM regulator for heaters with the algorithm for searching the maximum MPPT power point from solar panels. A buffer module containing capacitors, a choke, diodes is added to the regulator, which allows greater efficiency (up to 30%) and reduction of interference caused by PWM regulation.
and that I bought a new 50-gal water heater off Craigslist to use as a preheat tank. I have installed the water heater, and connected the controller to the bottom (stock) 4500w heating element. It has been operating a couple of days with no issues. With six used 190w panels, I've got 800-900w going to the element in full sun (8 - 8.5a into the 12.8 ohm resistor at 100v). Over the last two days (about 5 hrs of mostly sun each day) I've heated the tank from 70 F to 140 F. I haven't made the last connection to the existing water heater yet, so I'm just heating a static 50-gal tank of water. The temperature disconnect works, the controller shut off at my test set point of 60 C (140 F).
I will write this up for other folks' benefit, and link to it when done. Also, I will order the boost converter that Bill Taylor mentioned (thanks Bill!), and come up with a circuit to use my main solar array to drive the top heater element after my batteries are full.
Want to make use of those idle panels in the afternoons.
Coincidentally, last week I ordered
PWM MPPT Heater Charger Regulator Solar Photovoltaic Solar Panels Hot Water PV | eBay
PWM regulator for heaters with the algorithm for searching the maximum MPPT power point from solar panels. A buffer module containing capacitors, a choke, diodes is added to the regulator, which allows greater efficiency (up to 30%) and reduction of interference caused by PWM regulation.
and that I bought a new 50-gal water heater off Craigslist to use as a preheat tank. I have installed the water heater, and connected the controller to the bottom (stock) 4500w heating element. It has been operating a couple of days with no issues. With six used 190w panels, I've got 800-900w going to the element in full sun (8 - 8.5a into the 12.8 ohm resistor at 100v). Over the last two days (about 5 hrs of mostly sun each day) I've heated the tank from 70 F to 140 F. I haven't made the last connection to the existing water heater yet, so I'm just heating a static 50-gal tank of water. The temperature disconnect works, the controller shut off at my test set point of 60 C (140 F).
I will write this up for other folks' benefit, and link to it when done. Also, I will order the boost converter that Bill Taylor mentioned (thanks Bill!), and come up with a circuit to use my main solar array to drive the top heater element after my batteries are full.
Want to make use of those idle panels in the afternoons.
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