| 1 kV |
Voltage level equal to one thousand volts representing the upper limit of low voltage networks |
| 11 kV |
Typical distribution voltage level used for local electricity networks in the United Kingdom |
| 33 kV |
Medium voltage distribution and sub transmission level used for regional networks |
| 132 kV |
High voltage regional transmission level used widely in the United Kingdom |
| 230 V |
Standard single phase domestic supply voltage in the United Kingdom |
| 275 kV |
Extra high voltage transmission level used on the United Kingdom National Grid |
| 400 V |
Typical three phase low voltage supply used in commercial and industrial installations |
| 400 kV |
Highest transmission voltage used on the United Kingdom National Grid backbone |
| A |
Ampere unit of electric current |
| AC |
Alternating current electrical power where current periodically reverses direction |
| Ah |
Ampere hour unit of electric charge used in batteries |
| Albedo |
Reflectivity of ground surfaces affecting bifacial solar module performance |
| Aluminium |
Lightweight conductive metal widely used in solar frames cables and overhead conductors |
| Amtech |
Electrical power system design software used for protection coordination and cable calculations |
| BESS |
Battery energy storage system used to store electrical energy |
| Bifacial Module |
Solar module capable of generating electricity from both front and rear surfaces |
| Bond |
Financial security provided by contractors guaranteeing project performance obligations |
| Boron |
Chemical dopant used to create p type silicon semiconductor material |
| Busbar |
Conductive copper or aluminium bar used to distribute electrical current |
| Capacitor |
Electrical component storing energy in an electric field |
| COD |
Commercial operation date when a power plant begins commercial energy generation |
| Copper |
Highly conductive metal used in electrical cables transformers and equipment |
| DC |
Direct current electrical power flowing continuously in one direction |
| DNO |
Distribution network operator responsible for electricity distribution networks |
| ER |
Employer requirements technical specification issued to EPC contractors |
| GW |
Gigawatt unit of electrical power equal to one billion watts |
| GWp |
Gigawatt peak photovoltaic rated output |
| Harmonics |
Distortion of voltage or current waveforms caused by non linear electrical loads |
| Heat Pump |
Electrically driven device transferring heat from a lower temperature source to a heating system |
| IEC62548 |
International standard covering installation and safety of photovoltaic arrays |
| IEC62738 |
International photovoltaic module testing standard |
| IEA |
International Energy Agency global energy statistics organisation |
| IMD |
Insulation monitoring device used in floating DC systems |
| Inverter |
Power electronic device converting DC electricity into AC electricity |
| Isc |
Short circuit current produced when photovoltaic terminals are shorted |
| kV |
Kilovolt unit of electrical potential equal to one thousand volts |
| kVA |
Kilovolt ampere unit of apparent power |
| kVAR |
Kilovolt ampere reactive unit of reactive power |
| kW |
Kilowatt unit of electrical power |
| kWh |
Kilowatt hour unit of electrical energy |
| kWp |
Kilowatt peak photovoltaic rated output |
| LDs |
Liquidated damages contractual penalties applied when performance targets are not achieved |
| MC4 |
Standard DC connector used for photovoltaic module interconnection |
| MCCB |
Moulded case circuit breaker used in electrical distribution protection |
| MLPE |
Module level power electronics such as optimisers and microinverters |
| MOSFET |
Metal oxide semiconductor field effect transistor used in power electronics switching |
| MPPT |
Maximum power point tracking control algorithm used in solar inverters |
| MW |
Megawatt unit of electrical power equal to one million watts |
| MWp |
Megawatt peak photovoltaic rated output |
| MWh |
Megawatt hour unit of electrical energy |
| ODSL |
Outdoor dry sealing end high voltage cable termination |
| ONS |
Office for National Statistics United Kingdom statistics authority |
| PAC |
Performance acceptance certificate confirming plant meets contractual performance |
| Partial Discharge |
Localised electrical discharge in insulation indicating deterioration |
| PERC |
Passivated emitter rear cell photovoltaic technology |
| Perovskite |
Emerging photovoltaic semiconductor material used in high efficiency solar cells |
| PCS |
Power conversion system converting AC and DC power in battery storage installations |
| PV |
Photovoltaic technology converting sunlight into electricity |
| PVSyst |
Solar photovoltaic simulation software used for energy yield modelling |
| RTB |
Ready to build project status meaning permits and financing are completed |
| SLD |
Single line diagram simplified representation of electrical power systems |
| Snubber Circuit |
Electronic circuit used to suppress switching voltage spikes |
| SPD |
Surge protection device protecting equipment from transient voltages |
| Trefoil Cable Laying |
Three single core cables installed in triangular formation to reduce electromagnetic forces |
| TSO |
Transmission system operator responsible for high voltage electricity transmission networks |
| Transient Voltage |
Short duration voltage surge caused by switching operations or lightning |
| TUV Rheinland |
Certification organisation testing photovoltaic equipment |
| V |
Volt unit of electrical potential difference |
| VA |
Volt ampere unit of apparent power |
| VAR |
Volt ampere reactive unit of reactive power |
| W |
Watt unit of electrical power |
| Wh |
Watt hour unit of electrical energy |
| ∞ |
Infinite bus ideal grid reference with constant voltage and frequency |
| ⏚ |
Earth ground symbol representing electrical connection to earth |