Below is a glossary of the terms commonly used in the solar power and photovoltaic (PV) industry:

ABSORBER

In a PV (photovoltaic) system, this is the material that absorbs the photons to generate electrons.

Alternating Current is a type of electrical current that changes direction all the time between the positive and negative sides. This is the type of electricity that is supplied by the main utility supplier to the premises and is the most commonly used type of electricity for households.

AMBIENT TEMPERATURE

The temperature of the area.

AMPERE

Commonly known as Amps which is the unit of measure that shows the number of units that flow through the conductor. Amps = watts / volts

AMPERE HOUR

Commonly called Amp Hours (Ah) The measure of the units that flow through the conductor in an hour period. This is used to measure the capacity of the batteries.

ANTI-REFLECTION COATING

A thin coating of material that decreases the reflection of light and increases the transmission of light on the PV cell surface.

ARRAY

The solar (PV) panels that are mounted. One panel is known as a panel, but two or more are known as an array. These can be installed either in series or parallel.

AVERAGE DEMAND

The demand of power for a certain location over a period of time.

BATTERY

The sole purpose of the battery is to store the electricity not immediately utilized so that the battery can power the system when necessary.

BATTERY CAPACITY

The number of hours (ampere hours) that are drawn from a charged battery.

BATTERY LIFE

The life span of the battery.

CELL

An item that produces power from light. Cells are used as the building blocks for modules.

CHARGE CONTROLLER

A machine that can control the charging rate for the battery / ies.

CIRCUIT

The conductor through which the power flows.

CURRENT

The flow of the electric charge in a conductor (circuit) between two points.

CYCLE

The discharge and recharge of a battery.

DEEP CYCLE

– A type of battery that can be discharged to a large amount of battery capacity without any damage to the battery.

DEPTH OF DISCHARGE

Also known as DOD, the amp hours taken from a fully charged cell/battery.

DIRECT CURRENT

The flow of electricity flowing continuously in one direction.

DISCHARGE

The electrical energy taken from a battery.

EFFICIENCY

The ratio of energy (output power to input power). Shown in percentages.

ELECTRIC CURRENT

The flow of electrical energy (electricity) in a conductor, measured in amperes.

ELECTRIC GRID

An integrated system of electricity distribution, usually covering a large area.

ELECTRICITY

Energy resulting from the flow of charge particles, such as electrons or ions.

ENERGY

The capability of doing work; different forms of energy can be converted to other forms, but the total amount of energy remains the same..

ENERGY AUDIT

A survey that shows how much energy used in a home, which helps find ways to use less energy.

FIXED TILT ARRAY

A set of solar panels mounted at a fixed angle.

FREQUENCY

The number of cycles through which an alternating current moves in each second.

GEL BATTERY

A lead-acid battery wherein the electrolyte is made up of silica gel.

GRID

The electricity transmission and distribution system that links power plants to customers through high-power transmission line service.

GRID-TIED PV SYSTEM

A photovoltaic (PV) system in which the panel array acts like a power generating plant, in turn supplying power to the electricity grid.

HYBRID SYSTEM

A solar electric or photovoltaic (PV) system that includes other sources of electricity generation, such as wind or diesel generators.

INPUT VOLTAGE

Determined by the total power required by the alternating current loads and the voltage of any direct current loads. The larger the load, the higher the inverter input load.

INVERTER

A device that converts direct current electricity to alternating current either for stand-alone systems or to supply power to an electricity grid.

KILOWATT

Equal to 1 000 watts, a kilowatt (kW) is a unit of measure of the amount of electricity needed to operate equipment.

KILOWATT HOUR

The amount of kW generated over the period of one hour.

LEAD ACID BATTERY

Batteries that have plates that are made of pure lead, lead-antimony, or lead-calcium immersed in an acid electrolyte.

LOAD

The demand on an energy producing system. Load also refers o the energy requirements of equipment on a system and is normally noted in terms of amps or watts in reference to electricity.

MEGAWATT

Abbreviated to MW and equal to 1 000 kilowatts (kW) or 1 million watts (W).

MEGAWATT-HOUR

Abbreviated to MWh and is 1 000 Kilowatt hours or 1-million Watt hours

METER

An integral unit containing a number of photovoltaic (PV) cells.

MODULE

Determined by the total power required by the alternating current loads and the voltage of any direct current loads. The larger the load, the higher the inverter input load.

MONOCRYSTALLINE

This refers to the silicon that is drawn as a solitary homogenous crystal. These panels perform better in cooler or shadier areas.

MOUNTING EQUIPMENT/STRUCTURE

The structure and equipment used to place and secure the panels on the roof or building

MPP

– Known as the Maximum Power Point which is the point on the current-voltage curve of a module under light where the amount of current and voltage is at its maximum.

MPPT

Maximum Power Point Tracker which is a device used to operate the PV-generator at its Maximum Power Point under all conditions.

PARALLEL CONNECTION

A way to connect batteries or solar panels where they are wired together to increase the ampacity and leave the voltage as constant.

PEAK LOAD / DEMAND

The maximum amount of electricity demand or load in a specific window of time.

PHOTOVOLTAIC

Abbreviated to PV with the breakdown of the name meaning light (photo) and electrical potential (Volt), which basically means electricity from light. This is the name for the solar panels or modules.

PHOTOVOLTAIC (PV) ARRAY

The number of panels connected to a system to generate solar power.

POLYCRYSTALLINE

Also known as multi crystalline, the standard and more common type of solar panel.

SEALED MAINTENANCE FREE BATTERY

– A battery which, once purchased, requires no maintenance for its lifespan, apart from the required charging and discharging of the battery. These batteries have a captive electrolyte and resealing vent cap so no electrolyte can be added.

SERIES CONNECTION

A way to connect batteries or panels where the positive wires are to connected to the negative wires to create an increase in the voltage and keep the ampacity constant.

SOLAR POWER

– Power generated by the Sun’s rays

SOLAR PANEL

A flat plate designed to absorb the rays from the Sun in order to generate electricity or heating.

SINE WAVE INVERTER

An inverter or UPS that produces grid-quality using sine wave power forms.

THIN FILM PHOTOVOLTAIC (PV) PANEL

A solar panel comprising of sequential layers of thin film materials. Commonly known as the most efficient type of panel.

UPS

Uninterruptible Power Supply which provides continuous service during power outages by drawing from batteries either charged by the national grid or by solar power.

VOLT

The unit of force required to push a constant current of one ampere to flow through a resistance of one ohm.

WATT

Measurement of electric power at one point in time, either as capacity or demand. The lower the wattage, the less electricity the item or appliance uses and costs to run while in operation.