Alternative Energy Glossary
There are 154 entries in this glossary.All
| Term | Definition |
|---|---|
| Absorber |
In a photovoltaic device, the material that readily absorbs photons to generate charge carriers |
| AC |
see alternating current. |
| Activated Shelf Life |
The period of time, at a specified temperature, that a charged battery can be stored before its capacity falls to an unusable level. |
| Activation Voltage(s) |
The voltage(s) at which a charge controller will take action to protect the batteries. |
| Adjustable Set Point |
A feature allowing the user to adjust the voltage levels at which a charge controller will become active. |
| AIC |
See amperage interrupt capability. |
| Air mass (sometimes called air mass rati |
Equal to the cosine of the zenith angle-that angle from directly overhead to a line intersecting the sun. The air mass is an indication of the length of the path solar radiation travels through the atmosphere. An air mass of 1.0 means the sun is directly overhead and the radiation travels through one atmosphere (thickness). |
| Alternating Current (AC) |
A type of electrical current, the direction of which is reversed at regular intervals or cycles. In the United States, the standard is 120 reversals or 60 cycles per second. Electricity transmission networks use AC because voltage can be controlled with relative ease. |
| Ambient Temperature |
The temperature of the surrounding area. |
| Amorphous Semiconductor |
A non-crystalline semiconductor material that has no long-range order. |
| Amorphous Silicon |
A thin-film, silicon photovoltaic cell having no crystalline structure. Manufactured by depositing layers of doped silicon on a substrate. See also single-crystal silicon an polycrystalline silicon. |
| Amperage Interrupt Capability (AIC) |
direct current fuses should be rated with a sufficient AIC to interrupt the highest possible current. |
| Ampere (amp) |
A unit of electrical current or rate of flow of electrons. One volt across one ohm of resistance causes a current flow of one ampere. |
| Ampere Hour Meter |
An instrument that monitors current with time. The indication is the product of current (in amperes) and time (in hours). |
| Ampere-Hour (Ah/AH) |
A measure of the flow of current (in amperes) over one hour; used to measure battery capacity. |
| Angle of Incidence |
The angle that a ray of sun makes with a line perpendicular to the surface. For example, a surface that directly faces the sun has a solar angle of incidence of zero, but if the surface is parallel to the sun (for example, sunrise striking a horizontal rooftop), the angle of incidence is 90°. |
| Annual Solar Savings |
The annual solar savings of a solar building is the energy savings attributable to a solar feature relative to the energy requirements of a non-solar building. |
| Anode |
The positive electrode in an electrochemical cell (battery). Also, the earth or ground in a cathodic protection system. Also, the positive terminal of a diode. |
| Array |
see photovoltaic (PV) array. |
| Array Current |
The electrical current produced by a photovoltaic array when it is exposed to sunlight. |
| Array Operating Voltage |
The voltage produced by a photovoltaic array when exposed to sunlight and connected to a load. |
| Azimuth Angle |
The angle between true south and the point on the horizon directly below the sun. |
| Base Load |
The average amount of electric power that a utility must supply in any period. |
| Battery |
Two or more electrochemical cells enclosed in a container and electrically interconnected in an appropriate series/parallel arrangement to provide the required operating voltage and current levels. Under common usage, the term battery also applies to a single cell if it constitutes the entire electrochemical storage system. |
| Battery Capacity |
The maximum total electrical charge, expressed in ampere-hours, which a battery can deliver to a load under a specific set of conditions. |
