Tracking devices are available that keep modules or arrays facing the sun to increase output, or to reduce the number of modules required in the system. Suppliers of recreational vehicles, marine equipment, and PV systems sell DC lights and appliances, but they tend to be more expensive than AC appliances. The wiring in DC systems is also a consideration. Therefore, DC systems require much thicker wiring than standard AC wiring to operate safely and efficiently. Also, the high amperage capacity fuses and circuit breakers necessary in DC systems are expensive, and may be more difficult to obtain than standard 120 V AC types.
Thick wiring is also difficult to work with.
Powering AC appliances with a PV system requires an inverter. Some appliances that require high quality power, such as laser printers, may not run well or at all on the power output of some inverters. You should consult with inverter dealers or manufacturers to determine what types of appliances their inverter will or will not operate. Inverters for residential systems, though becoming more sophisticated, reliable, and less expensive, can still be costly. The homeowner has to consider the various tradeoffs in energy needs, lifestyle, costs, and spare parts' availability before choosing whether to use DC or AC power.