| Abbreviation | Definition |
|---|---|
| IECEC | International Energy Conversion Engineering Conference |
| IECM | Interleaving Energy Conservation Mode |
| IECO | International Energy Consultants Organisation |
| IEDR | Integrated Energy Data Resource |
| IEDSS | Integrated Energy Decision Support System |
| IEE | Industrial Energy Efficiency |
| IEE | Institute for Energy and the Environment |
| IEE | Institutes of Energy and the Environment |
| IEE | Intelligent Energy - Europe |
| IEEA | Industrial Energy Efficiency Accelerator |
| IEEA | Intelligent Energy Executive Agency |
| IEEB | Increasing Energy Efficiency in Buildings |
| IEEC | Industrial Energy Equipment Co |
| IEEC | Inland Empire Energy Center |
| IEEC | Interagency Energy Efficiency Committee |
| IEEC | International Energy Efficiency Certificate |
| IEED | Indian Energy and Economic Development |
| IEEFA | Institute for Energy Economics and Financial Analysis |
| IEEFA | Institute of Energy Economics and Fnancial Analysis |
| IEEJ | Institute of Energy Economic Japan |