These systems are less common than low temperature systems, and installation requires an experienced contractor and several weeks of project time. Payback is extended when the application is for air-conditioning. Domestic hot water can be a by-product of the absorption unit, and will defray operating costs somewhat. Photovoltaic Systems . Ample sunlight, low maintenance, high reliability, and widespread support make photovoltaic systems and attractive option for remote energy generation.
System design is flexible and easily expanded.
A development can be energized by a single centralized large array and battery storage, or smaller autonomous systems serving local areas, even individual dwelling units. Although there may be cost advantages for a centralized system, there are reliability advantages for a number of small modular systems with interchangeable components. Although there are many variables a typical hotel room or studio apartment could be powered by batteries of 300 amp hours at 12 volts, including a four-day reserve. This would include fans, lights, TV or stereo, an occasional high load such as a hair dryer or whirlpool bath, and a high-efficiency refrigerator. Peak loads such as cooking would be best handled by natural gas or propane.