Battery cycle: One discharge plus one re-charge equals one battery cycle.
Battery storage: A way to store energy. A battery can store electrical energy in a reversible chemical reaction.
Centralised energy system: Generation of electricity at large-scale centralized facilities.
Compressed air energy storage (CAES): A way to store energy. Excess electricity is used to compress air and store energy underground. The pressurized air is heated and released, driving a turbine to generate electricity.
Decentralised energy system: Synergy between several energy resources. Generate of electricity from many different resources.
Grid frequency: Frequency is the number of occurrences of a repeating event per unit of time. Grid frequency is the nominal frequency of alternating current oscillations in an electric power grid, from the power station to the end-user.
Hydrogen storage: A way to store energy. Electricity is converted into hydrogen by electrolysis, it is then stored and eventually re-electrified when needed.
Life cycle costs: Sum of recurring and one-time costs over the full life span (or a specified period) of a product, service or system.
Pumped hydro storage: A way to store energy. Excess electricity is used to pump water from a lower reservoir to a higher one, where it is stored. The water is released from the higher reservoir, passing through a hydro-power turbine to generate electricity.
Supercapacitors: A way to store energy. Supercapacitors store electrical energy at an electrode–electrolyte interface.