| ACER | Agency for the Cooperation of Energy Regulators |
| BGE | Bord Gáis Energy |
| CBA | Cost benefit analysis |
| CCPC | Competition and Consumer Protection Commission |
| CER | Commission for Energy Regulation |
| CRU | Commission for Regulation of Utilities |
| CSG | Consumer Stakeholder Group |
| DCCAE | Department of Communications, Climate Action and Environment |
| DfE | Department for the Economy (Northern Ireland) |
| DHPLG | Department of Housing, Planning, and Local Government |
| DPER | Department of Public Expenditure and Reform |
| DSO | Distribution System Operator |
| EPA | Environment Protection Agency |
| ERA | Electricity Regulation Act |
| ESB | Electricity Supply Board |
| ESBN | ESB Networks |
| GSF | Gas Safety Framework |
| HSA | Health and Safety Agency |
| IAA | Irish Aviation Authority |
| ICT | Information and Communication Technologies |
| IBP | Integrated Business Plan |
| IED | Industrial Emissions Directive (2010/75/EU) |
| IRCG | Irish Coast Guard |
| IPPC | Integrated pollution prevention and control |
| I-SEM | Integrated Single Electricity Market |
| JOC | Joint Oireachtas Committee |
| JSG | Joint Steering Group for the Single Electricity Market |
| KPI | Key performance indicator |
| LPG | Liquefied petroleum gas |
| MIC | Maximum import capacity |
| MSO | Marine survey office |
| MOU | Memorandum of understanding |
| NER | Network of Economic Regulators |
| NTMA | National Treasury Management Agency |
| OSCP | Oil spill contingency plan |
| PAFER | Performance assessment framework for economic regulators |
| PSF | Petroleum Safety Framework |
| PSO | Public Service Obligation |
| PWF | Public Water Forum |
| REFIT | Renewable energy feed-in-tariff |
| RGI | Registered gas installers |
| RIA | Regulatory Impact Assessment |
| SEM | Single Electricity Market |
| SEMC | SEM Committee |
| SEMO | Single Electricity Market Operator |
| SMP | System Marginal Price |
| SSB | Safety supervisor bodies |
| TAO | Transmission Asset Owner |
| TSO | Transmission system operator |
| UR | Northern Ireland Authority for Utility Regulation |
| WPAC | Water Policy Advisory Committee |
| WAREG | European Water Regulators |