This is a pretty good deal:
http://mailchi.mp/ironedison.com/our-biggest-sale-ever-nickel-iron-batteries-and-complete-solar-systems?e=3f8881df3eThe NiFe batteries s are bulkier and heavier , and probably shouldn't be discharged as much as this guy designs the systems to discharge, but are far better tan the Lead ones I bought-- These will last with proper watering for over 100 years. Mine? I will be lucky to get 20
Solar panels have been slowly dropping, and that complete 48 Volt Outback system is a pretty good deal. Its large enough to power most homes, A/C and all ( no baseboard heat) A normal home uses about 800 KW-Hrs a month, or around 28 a day. A 6.7kw Array should generate between 26 and 33 KW-hrs.. so this package is sized right and the batteries store 29 KW in total - so You have about a days worth of "extra" and more if you go into conservation mode and just run freezer, fridge, water pump and other essentials.
Be aware the math is funky. The system cost is $37K. You can tack on another 5K for wiring , and panels, and switches and other " Balance of system " items. If you install it yourself you can also claim the cost of your (or someone else's) labor, but now you will have to start proving stuff to the IRS if you are audited.
You can deduct 30% of the cost of installing your system straight off your taxes.. so if you pay more than 10-13K to the government in income tax NOW, then you can shift that payment to these guys. That is true only through 2019 , and then the amount you can deduct falls. ( unless they change the law, which they might..)
So around 11-13K is money you would normally have paid in taxes that now goes to the PV system dealer, along with another 25K or so out of your pocket. So still not "Cheap" but it is awesome when the lights stay on and it will pay itself off over about 20 years. You will not save money. You will simply pay your electric bill for the next 20 years, now at something near current rates . It will probably NOT add to the value of the home, so if you think you might move, don't do it. If you are at or near retirement and this is your house till you die, well this is another cost you won't pay later on your fixed income, no matter ow the Government tries to mess with oil prices, Coal production or other factors.
Solar IS a viable technology for local, personal use. Depending on local electricity prices the ROI is awful to poor. But you are gaining independence and insurance against future price changes.