Energy payback is the time period it takes for a wind turbine to generate as much energy as is required to produce the turbine in the first place, install it, maintain it throughout its lifetime and, finally, scrap it.

Energy monitoring and targeting techniques provide energy managers with feedback on operating practices, results of energy management projects, and guidance on the level of energy use that is expected in a certain period.

Energy modeling or energy system modeling is the process of building computer models of energy systems in order to analyze them.

A detailed heat loss and heat gain calculation for a building.

Governmental ministers that are charged with energy decisions and implementation of energy policies.

Energy markets that specifically deal in the trade and supply of energy.

An energy management system (EMS) is a system of computer-aided tools used by operators of electric utility grids to monitor, control, and optimize the performance of the generation or transmission system.

Energy Management Software (EMS) is a general term and category referring to a variety of energy-related software applications which may provide utility bill tracking, real-time metering, building HVAC and lighting control systems, building simulation and modeling, carbon and sustainability reporting, IT equipment management, demand response, and/or energy audits.

Used in predicting the energy necessary to operate the system for some prescribed time such as a month, year, or season.

Energy liberalisation refers to the liberalisation of energy markets, with specific reference to electricity generation markets, by bringing greater competition into electricity and gas markets in the interest of creating more competitive markets and reductions in price by privatisation.

In quantum physics, energy level splitting or a split in an energy level of a quantum system occurs when a perturbation changes the system.

A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy, called energy levels.

Energy laws govern the use and taxation of energy, both renewable and non-renewable.

An energy landscape is a mapping of possible states of a system.

An energy ladder shows the improvement of energy use corresponding to an increase in the household income.

The term energy input labeling involved producers of goods and services determining how much energy is used to produce their product, and then including that information on their product packaging.

The energy industry is the totality of all of the industries involved in the production and sale of energy, including fuel extraction, manufacturing, refining and distribution.

Energy harvesting is the process by which energy is derived from external sources, captured, and stored for small, wireless autonomous devices, like those used in wearable electronics and wireless sensor networks.

Energy gels are carbohydrate gels that provide energy for exercise and promote recovery, commonly used in endurance events such as running, cycling, and triathlons.

The energy functional is the total energy of a certain system, as a functional of the system's state.