Takže na baterky to není stavěné, prostě je to ongrid řešení. Ale návratnost tak 9.5+ let. Prostě uvidíme.
Forum SunMAX:
http://community.ubnt.com/t5/SunMAX/bd-p/SunMAX The SunMax hardware as advertised simply does not lend itself well to battery storage.
The inverters are all up on the roof with the panels, and are directly connected to them. If you want to charge batteries, you will need a charge controller and/or a more complex (read: expensive) microinverter and charge controller device + more wiring to the battery bank. Or you will need to intercept the output of the panels ahead of the microinverter(s) and connect it directly to a dedicated charge controller.
If you want to power the microinverters off your battery bank, you will need to run additional heavy gauge wiring BACK UP to the roof from the batteries. Not practical, so you will need a large dedicated inverter near the battery bank.
As eejimm noted, you will also need some means to automatically do a safe transfer from grid power to inverter power so as to not backfeed the grid.
The whole thing gets heinously complex and expensive.
If you want affordable battery storage AND grid tie, you do it with a panel array, a charge controller, a battery bank, and a grid-interactive inverter with automatic transfer switch. The microinverter-based configuration of the SunMax system is just not set up to do this. It will require a completely different collection of hardware. About the only thing that would not be significantly different will be the bare panels themselves.
Again, you must remember that the point of most residential grid-tie installs is to reduce your power bill and/or appear to be hip and trendy and lord it over your neighbors by having solar on your roof. Because of our penchant for power-gluttonous appliances and bigger homes than we actually need, it is generally impractical to put a std. residential home on an off-grid system unless we are willing to seriously scale back our lifestyles.
A battery-backed utility interactive system is not a bad idea, but unless you are willing to fork over the big $$$ necessary to buy a large kW inverter capable of running your refrigeration, electric water heater, and electric range simultaneously, you will need to reconfigure the house wiring such that those power hogs are not on the system if utility power goes down and you switch over to battery. Needless to say, this will be a hard thing to sell to Mr. and Ms. Jane Q. Public, who are used to flipping a switch for whatever, whenever.