Photovoltaic solar panels on a house roof.
Building-integrated photovoltaics (BIPV) are increasingly incorporated into new domestic and industrial buildings as a principal or ancillary source of electrical power,[41] and are one of the fastest growing segments of the photovoltaic industry.[42] Typically, an array is incorporated into the roof or walls of a building, and roof tiles with integrated PV cells can now be purchased. Arrays can also be retrofitted into existing buildings; in this case they are usually fitted on top of the existing roof structure. Alternatively, an array can be located separately from the building but connected by cable to supply power for the building.
Where a building is at a considerable distance from the public electricity supply (or grid) - in remote or mountainous areas – PV may be the preferred possibility for generating electricity, or PV may be used together with wind, diesel generators and/or hydroelectric power. In such off-grid circumstances batteries are usually used to store the electric power.
In locations near the grid, however, feeding the grid using PV panels is more practical, and leads to optimum use of the investment in the photovoltaic system. This requires both regulatory and commercial preparation, including net-metering and feed-in agreements. To provide for possible power failure, some grid tied systems are set up to allow local use disconnected from the grid. Most photovoltaics are grid connected. In the event the grid fails, the local system must not feed the grid to prevent the possible creation of dangerous islanding.
The power output of photovoltaic systems for installation in buildings is usually described in kilowatt-peak units (kWp).

In transport

PV has traditionally been used for auxiliary power in space. PV is rarely used to provide motive power in transport applications, but is being used increasingly to provide auxiliary power in boats and cars. Recent advances in solar race cars, however, have produced cars that with little changes could be used for transportation.

Standalone devices

Solar parking meter.
Until a decade or so ago, PV was used frequently to power calculators and novelty devices. Improvements in integrated circuits and low power LCD displays make it possible to power such devices for several years between battery changes, making PV use less common. In contrast, solar powered remote fixed devices have seen increasing use recently in locations where significant connection cost makes grid power prohibitively expensive. Such applications include parking meters, emergency telephones, temporary traffic signs, and remote guard posts & signals.