FAQ

Alternating current. An electric current that reverses its direction many times a second at regular intervals, typically used in power supplies.

Direct current. Is the unidirectional flow or movement of electric charge carriers (which are usually electrons). The intensity of the current can vary with time, but the general direction of movement stays the same always.

Charge regulator or battery regulator limits the rate at which electric current is added to or drawn from electric batteries. It prevents overcharging and can protect against overvoltage.

Florida solar energy center. FSEC is the largest and most active state-supported renewable energy and energy efficiency research, training, testing, and certification institute in the united states.

Also called tied to grid or grid tie system, is a semi-autonomous electrical generation or grid energy storage system which links to the mains to feed excess capacity back to the local mains electrical grid. When insufficient electricity is generated, or the batteries are not fully charged, electricity drawn from the mains grid can make up the shortfall.

Is a combination of an inverter, battery charger and transfer switch into one complete system. When ac power is available, the inverter/charger recharges the house batteries. It also allows any surplus ac power to pass through and power downstream ac loads, such as a television set or microwave oven. When ac is disconnected, the unit inverts dc battery power into ac electricity.

(symbol kwh, kw·h, or kw h) is a unit of energy equal to 1,000 watt-hours, or 3.6 megajoules. The kilowatt-hour is commonly used as a billing unit for energy delivered to consumers by electric utilities.

Is a device used in photovoltaics that converts direct current (dc) generated by a single solar module to alternating current (ac). The output from several microinverters is combined and often fed to the electrical grid.

A packaged, connected assembly of solar cells.

Or maximum power point tracker is an electronic dc to dc converter that optimizes the match between the solar array (pv panels), and the battery bank or utility grid. To put it simply, they convert a higher voltage dc output from solar panels (and a few wind generators) down to the lower voltage needed to charge batteries.

National Renewable Energy Laboratory. Is the united states’ primary laboratory for renewable energy and energy efficiency research and development. The national renewable energy laboratory (nrel) is a government-owned, contractor-operated facility, and is funded through the united states Department of Energy (DOE).

Refers to a photovoltaic module or to a set of solar photovoltaic (pv) modules electrically connected and mounted on a supporting structure.

Is a climatological indicator, measuring the duration of sunshine in given period for a given location on earth. It is a general indicator of cloudiness of a location and thus differs from insolation, which measures the total energy delivered by sunlight over a given period.