Off-grid remote power specialists - UK

Solar & Wind Energy Glossary

Debunking the jargon...

Solar & Wind Energy Glossary

Solar PV - photovoltaic - solar panels which produce electricity when exposed to light. Also called pv modules, pv cells and solar modules. The "pv" effect was first discovered in 1838 by nineteen-year-old Edmund Becquerel.

See also: Introduction to solar pv panels.


Wind Turbine Generator
- 'WTG' - a rotating machine which produces energy from the wind. The first known electricity generating windmill operated was a battery charging machine installed in 1887 by Professor James Blyth in Scotland.

See also: Introduction to wind generators.

Battery - batteries are used to store energy. They can be made of various materials however lead acid batteries are most commonly used for solar & wind applications. Lead-acid battery recycling is one of the most successful recycling programs in the world. The modern lead acid battery was developed in 1859 by French physicist Gaston Planté.

See also: Introduction to deep cycle batteries.


DC to AC Power Inverter
- these devices convert DC power as stored in batteries into AC power as found in a house. They are very convenient, however they do waste power when on standby and as such are not recommended for lighting, refrigeration or other applications where the inverter is on for longer periods of time.

See also: Introduction to power inverters.

Charge Controller / Regulator - these devices are primarily designed to prevent the batteries being overcharged, however the more advanced units also offer a variety of information such as charging current, battery voltage and some even log historical performance data.

See also: Introduction to charge controllers.

Mounting Frame - used to mount solar pv modules. They can range from being a simple supporting framework, through to a fully automated tracking structure which follows the sun.


DC to DC Converter - these devices convert a dc voltage supply into another dc voltage, such as a 24v to 12v converter. They are generally more efficient than using AC inverters, especially for devices such as laptops or mobile phones.


Low Voltage Disconnect - LVD - these devices disconnect a load from the batteries to prevent over discharge of a battery. Over discharge is one of the most common ways of killing a battery and an LVD unit is essential on most power systems.


Maximum Power Point Tracking - MPPT - a technology used in newer charge controllers which allows more power to reach the batteries. This is achieved with a very high efficiency dc to dc converter - which converts the normal 17.4v coming from the solar panel into 13.7v to charge the battery. As a result the charging current is higher - sometimes by up to a 33% gain.


'Factor Four' - a term used to describe outstanding efficiency. The idea behind FACTOR FOUR is that natural resources can be used more efficiently in all domains of daily life, either by generating more products, services and quality of life from the available resources, or by using less resources to maintain the same standard. This idea was first put forward in the RMI book "Factor Four: Doubling Wealth – Halving Resource Use"

Factor Four has now been superceeded by the more ambitious Factor 10xE Engineering, please visit the RMI's website for more details.



Cost effectiveness pyramid for on-grid buildings...