| STP | Shielded Twisted Pair | In English | |
| SuScT | Superconductor Science Technology | In English | → Serial publications, periodicals |
| SvPS | Soviet Physics Semiconductors | In English | → Serial publications, periodicals → Electronics |
| SWEB | South Western Electricity Board | In English | |
| SWIFET | Short-Wave Infrared Field Effect Transistor | In English | → Electronics |
| SWIFET | Switched Field Effect Transistor | In English | → Electronics |
| SZPC | Shandong Zhonghua Power Company | In English | |
| TAB | Tape Automated Bonding | In English | → Electronics |
| TAPIR | Transformateur d'Alimentation Provisoire Intégré sur Remorque | In French | → Food technology |
| TARTAM | TArif Réglementé Transitoire d'Ajustement du Marché | In French | → Prices |
| TDR | Time Domain Reflectometer | In English | → Electronics |
| TE | Timing Electronics | In English | → Electronics |
| TEA | Tranche en Arrêt | In French | → Nuclear technology |
| TEF | Tranche en Fonctionnement | In French | → Nuclear technology |
| TEGI | Tractebel Electricity & Gas International | In English | → Energy economics |
| TekEl | Tekhnicheskaia Elektrodinamika = TekEL | Технiчна електродинамiка | In Russian |
In Russian | → Serial publications, periodicals |
| TekEL | Технiчна електродинамiка = TekEl (look above) |
In Russian | → Serial publications, periodicals |
| TEM | Tranche en Marche | In French | → Nuclear technology |
| TEMASOL | Total EDF Maroc Solaire | In French | → Energy economics |
| TEO | Transport Électricité Ouest | In French | |
| TERA | Transport Électricité Rhône-Alpes | In French | |
| TES | Transactions Électroniques Sécurisées | In French | → Networks, communication → Electronics → Telecommunications |
| TESE | Transport Électricité Sud-Est | In French | |
| TESE | Technologies et Économie des Sytèmes Électriques | In French | → Energy economics |
| TESO | Transport Électricité Sud-Ouest | In French | |
| TFT | Thin Film Transistor | In English | → Electronics |
| THEMIS | Technologies et Modélisation des Infrastructures des Systèmes Électriques | In French | |
| THT | Through Hole Technology | In English | → Electronics |
| TME | Transfer Multisort Electronic | In English | → Electronics |
| TPN | Tarif de Première Nécessité | In French | → Prices |
| TQFP | Thin Quad Flat Pack | In English | → Electronics |
| TTENP | Transport Électricité Normandie Paris | In French | |
| TTL | Transistor-Transistor Logic | In English | → Electronics |
| TURP | Tarifs d'Utilisation des Réseaux Publics | In French | |
| UAPET | Updates in Applied Physics and Electrical Technology | In English | → Serial publications, periodicals → Engineering, technology |
| UCPTE | Union pour la Coordination de la Production et du Transport d’Électricité | In French | → Organizations and associations |
| UEA | United Energy Associates | In English | → Energy economics → Environmental technology, water supply, waste management |
| UES | Unified Energy System = ЕЭС | Единые Энергетические Системы | In Russian |
In English | → Energy economics |
| UFE | Union Française de l’Électricité | In French | → Organizations and associations |
| UICC | Universal Integrated Circuit Card | In English | → Electronics |
| UNIPE | Unité Nationale de l’Ingénierie du Parc en Exploitation | In French | |
| UNIPEDE | UNion Internationale des Producteurs Et Distributeurs d'Énergie Électrique | In French | → Organizations and associations |
| UPS | Uninterruptible Power System | In English | |
| USA/RC | Universities Space Automation/Robotics Consortium | In English | |
| UTE | Union Technique de l'Électricite | In French | → Organizations and associations |
| UTE | Union Technique de l'Électricité et de la Communication | In French | → Organizations and associations → Telecommunications |
| UTE | Usina Termelétrica Norte Fluminense (www.utenortefluminense.com.br) | In Portuguese | → Energy economics |
| UTP | Unshielded Twisted Pair | In English | |
| UVD | Undervoltage Device | In English | |
| UVPE | UV/Video Processing Electronics | In English | → Image processing → Electronics |
| V | Volt | In many languages | → Electricity, magnetism, electromagnetism |
| VCC | Voltage Change Controller | In English | |
| VCO | Voltage Control Operator | In English | |
| VCO | Voltage-Controlled Oscillator | In English | |
| VCO | Voltage Control Oscillator | In English | |
| VCT | Voltage Control Transfer | In English | |
| VDE | Verband der Elektrotechnik, Elektronik und Informationstechnik | In German | → Organizations and associations → Electronics → Telecommunications |
| VEEI | Vehicle Electrical Engine Interface | In English | → Vehicle engineering |
| VEÖ | Verband der Elektrizitätsunternehmen Österreichs | In German | → Organizations and associations |
| VHD | Véhicule Hybride Diesel/Électrique | In French | → Vehicle engineering |
| VHSIC | Very High Speed Integrated Circuit | In English | → Electronics |
| VLSIC | Very Large Scale Integrated Circuit | In English | → Electronics |
| VM | Voltmeter | In English | |
| VOGUE | Vers l’Optimisation de la Gestion et de l’Utilisation de l’Énergie | In French | → Energy economics |
| VOM | Voltohmmeter | In English | |
| VPD | Variable Power Divider | In English | → Energy economics |
| VPK | Volts Peak | In English | |
| VPP | Virtual Power Plant | In English | → Energy economics |
| VR | Voltage Relay | In English | |
| VR | Voltage Regulator | In English | |
| VSO | Very Stable Oscillator | In English | |
| VTVM | Vacuum Tube Voltmeter | In English | |
| W | Watt | In many languages | → Physics |
| W&C | Wire and Cable | In English | → Electronics → Telecommunications |
| WCSAR | Wisconsin Center for Space Automation and Robotics | In English | → Mechanical engineering → Electronics → Spaceflight engineering, astronautics |
| WEEE | Waste Electrical and Electronic Equipment = DEEE | Déchets des équipements électriques et électroniques | In French |
In English | → Electronics → Environmental technology, water supply, waste management |
| ZCS | Zero Current Switch | In English | → Electronics |
| ZECK | Zespół Elektrociepłowni Wrocławskich "Kogeneracja" (www.kogeneracja.com.pl) | In Polish | → Energy economics |
| ZECW | Zespół Elektrociepłowni Wybrzeże | In Polish | |
| ZeIE | Zeitschrift elektrische Informations- und Energietechnik | In German | → Serial publications, periodicals → Energy economics |
| ZVS | Zero Voltage Switch | In English | → Electronics |
| ЕЭС | Единые Энергетические Системы = UES (look above) |
In Russian | → Energy economics |
| ОГК | Оптовая генерирующая компания = OGK | Optovaya Giéniérirouyouchtchaya Kompaniya | In Russian |
In Russian | → Energy economics |
| ОГК-1 | Оптовая генерирующая компания № 1 (www.ogk1.com) | In Russian | → Energy economics |
| ОГК-2 | Оптовая генерирующая компания № 2 (www.ogk2.ru) | In Russian | → Energy economics |
| ОГК-3 | Оптовая генерирующая компания № 3 (www.ogk3.ru) | In Russian | → Energy economics |
| ОГК-4 | Оптовая генерирующая компания № 4 (www.ogk-4.ru) | In Russian | → Energy economics |
| ОГК-5 | Оптовая генерирующая компания № 5 (www.ogk-5.com) | In Russian | → Energy economics |