My island in the sun is in fact a part of my home appliance collection (island) I've decided to power via a system designed to collect and store some of my daytime produced RTS (roof top solar) electricity for use at night. The appliances are my kitchen refrigerator, TV, audio, PVR and internet modem router mass storage devices and cordless 'phone base station.
An added benefit of this island is it's protected against power failures. There's no point contemplating a battery installation but still being exposed to grid power failures. So it's worth mentioning at this point that any inclination on your part to explore "battery storage" offerings by power companies or solar suppliers must include the question about "redundancy", i.e. will the "battery package" you're considering spending $,000's on, actually continue to provide uninterrupted power in the event of a blackout? If your supplier answers "Yes" make absolutely sure you have a statement to that effect included in your purchase contract, in very large letters, and get them to initial that line.At the moment my island is operational, albeit with lead acid batteries that are recovered, so my storage capacity and reliability are not optimal, but it has served as a test bed to prove the concept and provide much data for analysis.
The battery voltage I selected was 48V as that made the current demands safer to handle in a domestic environment. Trying to use 12V to generate 1.5kW for say, a dishwasher, would involve well over 100Amps of current in a 12V system, while the 48V configuration will only need a quarter, or about 25A, much easier to wire and much safer in general.
My inverter charger is a cheap PowerJack 5000W I picked up new for under $400AUD delivered. It has a few shortcomings, vis a vis remote control (which I'll attempt to provide with suitable, safe modification) and quality of build. On the plus side it affords a virtual UPS capability and is actually quite a good unit for consideration in marine and caravan installations.
The inverter charger is pictured above, with the DC charge/discharge monitor in front right. This enables monitoring of battery status.
I have already collected a lot of data about operation and performance, and those details will be discussed in another post. Suffice to say the setup works as intended but will benefit from improved batteries, with a Li-ion assembly being planned.