priceless.Ihave an unpowered storage garage and can if needed run lights for several days on a loose spare van battery.very handy when i run out of working room.have also used same for occasional blackouts for several days,runs tv,pvr and computor.the trick is to make sure all unit u plug in are low consumption.energy saving compact lights use the least.i check the current draw on every unit for amperage and use lowest.but,limit your useage.even a van battery connected to van alternator and running will run out of storage charge with hungry consumers.limit ureself to an inverter of no more than 500-600 watts.and forget using kettles.
caine
September 2008