Enphase M250 Specs for off-grid, tips and tricks and results

[J.P.M.]

you mean you are not planning to move

Not anymore. Too old and too lazy. Besides, IMO, I'm now pretty much in the belly of the beast for about the best weather on the planet.

[lkruper]

We are all interested to see the pvoutput graphs of the solar community you set up there with Solarddy.

I think Mars might be better.

[ButchDeal]

I think Mars might be better.

yeah, no (less than half earth):

http://ccar.colorado.edu/asen5050/projects/projects_2001/benoit/solar_irradiance_on_mars.htm

http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html

Mercury, now (at least the half of the planet facing the sun) YES, (6.6 times as much as earth)

http://nssdc.gsfc.nasa.gov/planetary/factsheet/mercuryfact.html

[lkruper]

yeah, no (less than half earth):

http://ccar.colorado.edu/asen5050/projects/projects_2001/benoit/solar_irradiance_on_mars.htm

http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html

Mercury, now (at least the half of the planet facing the sun) YES, (6.6 times as much as earth)
http://nssdc.gsfc.nasa.gov/planetary...rcuryfact.html

!!!!

[SunEagle]

yeah, no (less than half earth):

http://ccar.colorado.edu/asen5050/projects/projects_2001/benoit/solar_irradiance_on_mars.htm

http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html

Mercury, now (at least the half of the planet facing the sun) YES, (6.6 times as much as earth)
http://nssdc.gsfc.nasa.gov/planetary...rcuryfact.html

Now Mercury sounds very bright and very hot.

[michaellong30]

Hi Solarddy, Syedamerali, and Everyone else.

I'm looking at the enphase M250s for use in a 1.kW RV based system. I've found this discussion very interesting. Has anyone else progressed with this islanded M250 concept recently? I'm looking at a 240VAC UPS modification to generate my "utility signal" with some form up "dump load" to deal with excess generation from the M250s.

Any update on progress/failures/tip/etc.. would be greatly appreciated.

Thank you,
-M

[sensij]

I'm looking at the enphase M250s for use in a 1.kW RV based system.

Why would want to use microinverters? A normal charge controller (if you have batteries) works well. If you have enough shade that you think you need microinverters, you need to stop and rethink what you are doing.

[ButchDeal]

Hi Solarddy, Syedamerali, and Everyone else.

I'm looking at the enphase M250s for use in a 1.kW RV based system. I've found this discussion very interesting. Has anyone else progressed with this islanded M250 concept recently? I'm looking at a 240VAC UPS modification to generate my "utility signal" with some form up "dump load" to deal with excess generation from the M250s.

Any update on progress/failures/tip/etc.. would be greatly appreciated.

Thank you,
-M

This is a huge mistake. An AC coupled system is very complex and UPS systems are not designed or likely going to work in this configuration. They have no way to control the micros or the dump load. Worse UPS has an AC input and an AC output. They do not feed power out the input or take power in on the input side. This configuration will not work with AC coupling like a bymodal inverter which has two AC connections but canbfeed AC out on both and one is usually bidirectional.

[SunEagle]

Hi Solarddy, Syedamerali, and Everyone else.

I'm looking at the enphase M250s for use in a 1.kW RV based system. I've found this discussion very interesting. Has anyone else progressed with this islanded M250 concept recently? I'm looking at a 240VAC UPS modification to generate my "utility signal" with some form up "dump load" to deal with excess generation from the M250s.

Any update on progress/failures/tip/etc.. would be greatly appreciated.

Thank you,
-M

Unfortunately a UPS will not be able to mimic a "grid connection" to make your micro inverters work. You need a lot more than just the correct voltage and frequency to fool any grid tie inverter that it is connected to a working "grid".