First let me explain my whole system so you can see the whole picture.
I have since 1983 had 2 4x8 solar hot water panels south facing on my roof is what's know to us old timers as a drain back system . That is when its gets cold or in my case nearly every night on a timer its drains down so it cannot freeze. This system is direct system meaning the water is in the copper tubes in the panel and gets it heat from the black painted flat copper panels that the tubes are soldered to . This water is pumped down on a differential thermostat when it gets hot enough . This heater water goes into a 80 gallon Ream solar tank with 4 fittings directly.its just a storage solar tank.The solar tank feeds my 40 gallon natural gas water heater. I know this system very well and have spares to keep it active ( I even have a spare tank)and like it very much-thanks Jimmy Carter for paying for it in the 80s.I installed three such system back then.
Now in 2020 I installed a 9.6 KW solar panel system (24 400 watt) ground mount system that feeds a 22.5 kilowatt lithium battery bank. I have a sol-ark 12k inverter that works the whole system. I did the entire install my self and am still connected to the grid and still use some small amounts of power now and then (I do not have a contract with the power utility ) None of our power backfields the grid as I have limiters on the inflow wires to house service.
We live in a rainy mild climate in Nor-cal near the coast in the redwood forest area north of Eureka Ca.. We do get lots of sun 5 miles inland in 8 months and it's a bit cloudy and rainy in winter months with some shading on system Nov-Dec-Jan-Feb.
I also have a hot water smart pump that taps into bottom of said gas water heater that provides instant hot water at all taps (grundfuss smart pump) a super simple system. The only way hot water from solar tank gets to water heater is when demand draws it into gas water heater (you turn oil hot water in house-that the demand)
Now this whole tank system is on the north side of house in outside shed built for this stuff (central vac and water filters and calcite system from well is also in this two door larger 4x8 attached shed to home wall.
I'm thinking of relapsing my gas water heater with a new heat pump style which just used electric as we have plenty 8 months of the year . I think it will cost us the 4 months when we buy power and we live in the second most expensive power rates in the country other than Maine.
I know these heat pumps are best in heated areas and ours will not be as its north side but our climate is mild year around with only some minor freezing now and then winter wise. One thing on note is now my excess power is counter to a 220 stinger water heater element in solar tank now which I would have to turn off if I got the heat pump water heater. I have read up on these units and am on the fence whether this makes sense or is my gas unit cheaper to run. I still need the smart Grufus pump on water heater drain line for hot water loop . The climate is warm summers here with lots of 80 degree days and a lot of mild 60s in split seasons
The last note is we have 3 Mr cool mini splits for heating and cooling now I installed over the past 3 years as well. The water heater is the last step
any thoughts on is this a good move over the gas water heater now. I need to crunch the gas numbers still
any thoughts I'm missing?
I have since 1983 had 2 4x8 solar hot water panels south facing on my roof is what's know to us old timers as a drain back system . That is when its gets cold or in my case nearly every night on a timer its drains down so it cannot freeze. This system is direct system meaning the water is in the copper tubes in the panel and gets it heat from the black painted flat copper panels that the tubes are soldered to . This water is pumped down on a differential thermostat when it gets hot enough . This heater water goes into a 80 gallon Ream solar tank with 4 fittings directly.its just a storage solar tank.The solar tank feeds my 40 gallon natural gas water heater. I know this system very well and have spares to keep it active ( I even have a spare tank)and like it very much-thanks Jimmy Carter for paying for it in the 80s.I installed three such system back then.
Now in 2020 I installed a 9.6 KW solar panel system (24 400 watt) ground mount system that feeds a 22.5 kilowatt lithium battery bank. I have a sol-ark 12k inverter that works the whole system. I did the entire install my self and am still connected to the grid and still use some small amounts of power now and then (I do not have a contract with the power utility ) None of our power backfields the grid as I have limiters on the inflow wires to house service.
We live in a rainy mild climate in Nor-cal near the coast in the redwood forest area north of Eureka Ca.. We do get lots of sun 5 miles inland in 8 months and it's a bit cloudy and rainy in winter months with some shading on system Nov-Dec-Jan-Feb.
I also have a hot water smart pump that taps into bottom of said gas water heater that provides instant hot water at all taps (grundfuss smart pump) a super simple system. The only way hot water from solar tank gets to water heater is when demand draws it into gas water heater (you turn oil hot water in house-that the demand)
Now this whole tank system is on the north side of house in outside shed built for this stuff (central vac and water filters and calcite system from well is also in this two door larger 4x8 attached shed to home wall.
I'm thinking of relapsing my gas water heater with a new heat pump style which just used electric as we have plenty 8 months of the year . I think it will cost us the 4 months when we buy power and we live in the second most expensive power rates in the country other than Maine.
I know these heat pumps are best in heated areas and ours will not be as its north side but our climate is mild year around with only some minor freezing now and then winter wise. One thing on note is now my excess power is counter to a 220 stinger water heater element in solar tank now which I would have to turn off if I got the heat pump water heater. I have read up on these units and am on the fence whether this makes sense or is my gas unit cheaper to run. I still need the smart Grufus pump on water heater drain line for hot water loop . The climate is warm summers here with lots of 80 degree days and a lot of mild 60s in split seasons
The last note is we have 3 Mr cool mini splits for heating and cooling now I installed over the past 3 years as well. The water heater is the last step
any thoughts on is this a good move over the gas water heater now. I need to crunch the gas numbers still
any thoughts I'm missing?
Last edited: