Dear all
I have searched for quite a bit on this forum and could not find a topic to cover exactly my question. But if you know a thread, I’ll appreciate if you can link it here. Thanks.
I built a 6kWh lifepo4 24V battery a few years ago connected to a Growatt 3000 TL LVM which has a 1500W inverter and 150VDC max solar input. Right now it is used as UPS only with grid power only. I have no solar currently.
Since I am in Portland Oregon, with buried power cables, I rarely have power outages. Plus the state is almost only on renewables with all the dams we have. So power outages are rare in general.
I still have a UPS because for these couple of days even now and then where there are power outages, mostly due to accidents taking down power poles. I know sounds crazy but it happens once a year for some reasons. The longest period I had no power was 2 days.
My battery was always enough to cover my outages but without heat. I did a few tests to run my small heat pump on it and it works. It only draws 800W if I put it on low setting and is enough to heat one room which can be a good backup for those winter days. In summary I am looking at a last resort backup power system, not a fully automated transparent system capable of running my whole house like nothing happened.
I am considering adding 8kW of Tesla solar without Powerwall since there is no payback with Powerwall in Oregon (net metering), no off peak pricing and a 8kW will not generate excess energy over a year.
I am trying to find a way to have the possibility to charge my power bank during an outage with my grid tie solar. I understand it is very complicated to do it with the Tesla inverter. Hence I thought it could be a good idea to have a DC switch which could send the solar DC power directly to my off grid system, bypassing the entire Tesla inverter. By doing so, it will still be code compliant on the AC/grid side. To power my loads I’m planning on a subpanel connected to a generator switch to isolate my emergency AC subpanel from the grid.
Is this the best approach? Is there a better best practice?
My growatt only allows 150VDC which is probably not enough at all since Tesla inverters seems to be 600VDC. With 14 panels at 41VDC open each, I will hit the 600V but it’s not clear to me if Tesla would wire it this way. Even if they split the solar in two it would be stilll 300VDC, way above my growatt. What can be my options here? I could think of adding an 600V mppt to generate lower voltage for my growatt to then charge my battery. Yes not efficient but I don’t really care since I won’t be able to absorb all the energy and power anyway. I can also change my growatt to a new one with 600V input. Any other idea?
Thank you
I have searched for quite a bit on this forum and could not find a topic to cover exactly my question. But if you know a thread, I’ll appreciate if you can link it here. Thanks.
I built a 6kWh lifepo4 24V battery a few years ago connected to a Growatt 3000 TL LVM which has a 1500W inverter and 150VDC max solar input. Right now it is used as UPS only with grid power only. I have no solar currently.
Since I am in Portland Oregon, with buried power cables, I rarely have power outages. Plus the state is almost only on renewables with all the dams we have. So power outages are rare in general.
I still have a UPS because for these couple of days even now and then where there are power outages, mostly due to accidents taking down power poles. I know sounds crazy but it happens once a year for some reasons. The longest period I had no power was 2 days.
My battery was always enough to cover my outages but without heat. I did a few tests to run my small heat pump on it and it works. It only draws 800W if I put it on low setting and is enough to heat one room which can be a good backup for those winter days. In summary I am looking at a last resort backup power system, not a fully automated transparent system capable of running my whole house like nothing happened.
I am considering adding 8kW of Tesla solar without Powerwall since there is no payback with Powerwall in Oregon (net metering), no off peak pricing and a 8kW will not generate excess energy over a year.
I am trying to find a way to have the possibility to charge my power bank during an outage with my grid tie solar. I understand it is very complicated to do it with the Tesla inverter. Hence I thought it could be a good idea to have a DC switch which could send the solar DC power directly to my off grid system, bypassing the entire Tesla inverter. By doing so, it will still be code compliant on the AC/grid side. To power my loads I’m planning on a subpanel connected to a generator switch to isolate my emergency AC subpanel from the grid.
Is this the best approach? Is there a better best practice?
My growatt only allows 150VDC which is probably not enough at all since Tesla inverters seems to be 600VDC. With 14 panels at 41VDC open each, I will hit the 600V but it’s not clear to me if Tesla would wire it this way. Even if they split the solar in two it would be stilll 300VDC, way above my growatt. What can be my options here? I could think of adding an 600V mppt to generate lower voltage for my growatt to then charge my battery. Yes not efficient but I don’t really care since I won’t be able to absorb all the energy and power anyway. I can also change my growatt to a new one with 600V input. Any other idea?
Thank you
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