A breaking wave or breaker is a wave whose amplitude reaches a critical level at which some process can suddenly start to occur that causes large amounts of wave energy to be transformed into turbulent kinetic energy.

Breaking capacity or interrupting rating is the current that a fuse, circuit breaker, or other electrical apparatus is able to interrupt without being destroyed or causing an electric arc with unacceptable duration.

Biofuel is fuel that is produced through contemporary processes from biomass, rather than by the very slow geological processes involved in the formation of fossil fuels, such as oil.

Bioethanol is produced by fermenting plant-derived sugars to ethanol, using a similar process to that used in beer and wine-making.

Bioenergy with carbon capture and storage (BECCS) is the process of extracting bioenergy from biomass and capturing and storing the carbon, thereby removing it from the atmosphere.

Bioenergy is energy made from biomass or biofuel.

Common feedstock used in biodiesel production include yellow grease (recycled vegetable oil), "virgin" vegetable oil, and tallow.

Biodiesel production is the process of producing the biofuel, biodiesel, through the chemical reactions of transesterification and esterification.

Biodiesel is a form of diesel fuel derived from plants or animals and consisting of long-chain fatty acid esters.

Biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi.

Biodegradable waste includes any organic matter in waste which can be broken down into carbon dioxide, water, methane or simple organic molecules by micro-organisms and other living things by composting, aerobic digestion, anaerobic digestion or similar processes.

The bioconversion of biomass to mixed alcohol fuels can be accomplished using the MixAlco process.

Biochar is charcoal that is produced by pyrolysis of biomass in the absence of oxygen; it is used as a soil ameliorant for both carbon sequestration and soil health benefits.

Biobased economy, bioeconomy or biotechonomy refers to economic activity involving the use of biotechnology and biomass in the production of goods, services, or energy.

Binding energy is the smallest amount of energy required to remove a particle from a system of particles or to disassemble a system of particles into individual parts.

A binary cycle power plant is a type of geothermal power plant that allows cooler geothermal reservoirs to be used than is necessary for dry steam and flash steam plants.

The maximum power coefficient (Cp = 59.3) of a theoretically perfect wind turbine as described by scientist Albert Betz.

A betavoltaic device (betavoltaic cell or betavoltaic battery) is a type of nuclear battery which generates electric current from beta particles (electrons) emitted from a radioactive source, using semiconductor junctions.

A beta particle is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay.

Beta decay (β-decay) is a type of radioactive decay in which a beta particle (fast energetic electron or positron) is emitted from an atomic nucleus, transforming the original nuclide to an isobar of that nuclide.