Since most alternative power is not steady, solar on at day time, wind only when it blows etc. There is need for storage and the best storage is a battery. For information about batteries try these links
Deep Cycle FAQ
Inverters and Power
The ability of inverter to carefully charge and discharge a battery at the rate required by the solution is the ultimate in running a power system. The ability to stack (expand) is a plus. The management of power is handle well by the experts at Victron.