Off-Grid Energy Strategy
All loads can run during the day if one devises a smart energy system for a home and has access to low cost photovoltaic power such as from Sunelec.
Further, one can run most loads on solar: cooking with high efficiency induction cooktop; hot water with minitank heaters; AC and heat with heat pump. Fridge as a Freezer to Fridge Conversion. Then the only loads left for the night are lights and computers if one is a late night information worker.
Thus, there is a low level of power that is required during the night. This power can be produced with a small battery bank, or with a house generator. It seems that a sensible way to achieve this would be via nickel iron batteries - a small backup system that lasts for a long time. For a household that runs 3 hours of 200W - that would be under 1 kWhr of power.
The most energy-saving route is the nickel-iron. If you examine [1] from Nickel-Iron Battery Quotes - a 2kWhr system would cost $1100 in nickel-iron batteries. If this is true - ie, if the batteries can really be discharged down to near full - then this is a promising way to solve the storage issue. The key is superefficiency by blowing out of proportion the available solar photovoltaic power during the day - and coasting at night with a small load. A backup house generator can complete the whole package - a small remote control or auto transfer switch generator converted from a portable generator. This is possible because PV panels now cost about 34 cents per watt.