Fabrication industries - Businesses engaged in the production of manufactured goods; excluding the generation of energy for manufacturing processes. This is in contrast to the term “manufacturing industry”, which sometimes encompasses both energy generation and goods fabrication.

Fast neutron reactors - Type of nuclear reactors that can utilize nuclear waste from thermal reactors as feedstock and operate at higher efficiencies.

F-class gas steam turbines - Advanced technology gas turbines, which are rotary engines that extract energy from a flow of combustion gas at thermal power plants, that are more efficient and reliable than conventional gas turbines.

Filtration - Removing solid particulate matter suspended in water by passing the water through permeable fabrics or porous layers of soil.

First generation biofuels - Fuels that use feedstock such as sugary or starchy materials that are then fermented into bioethanol. Also includes oil from seeds that can be used in biodiesel.

Flue gas denitration (De-No_x) - System that removes nitrogen oxides from flue gas.

Flue gas desulfurization (De-So_x) - System that removes sulfur oxides from flue gas.

Flue gas purification - Process by which flue or exhaust gases are cleaned in order to remove nitrogen oxides, soot and other particulates.

Fresnel mirrors - Solar thermal energy collectors that consist of a series of long, narrow, slightly curved mirrors that focus the light onto linear receivers positioned above the mirrors to be eventually converted into electricity.

Fuel cell vehicles (FCV) - Vehicles propelled by an electric motor using electricity generated through a chemical process within a fuel cell, which requires hydrogen fuel and oxygen from the air as feedstock.

Fuel economy standards - Standards that regulate the amount of fuel required to move the automobile over a given distance.

Fuel switching - Ability to make use of alternative fuels either by using multiple fuels simultaneously or by switching between fuels.