Increases in efficiency, power density, and economy
of electricity storage technologies
will benefit the development
of the distributed renewable energy economy
by lessening dependence on the electrical grid
and giving greater autonomy to the micro-producer.
The following is a crude and incomplete classification
of renewable energy storage systems.
store energy in the form of the potential energies of chemical reactions
usually involving oxidation by ambient oxygen.
Electrolysis of water
- Biological production
- Hydrocarbon reforming
- Thermochemical processes
- Carbon-based, liquid or gas
- Extracting organic compounds from crops
- Collecting biogas from waste streams
- Fuel cell operation
- Carbon-based, solid
- Batteries -
are charged by and supply electricity.
- Mechanical systems
- Compressed air storage
- Elevation-separated liquid reservioirs
- Rechargable chemical batteries -
store energy in the form of the potential energies of largely ionic compounds
formed in a reversable reaction by the supply of a reverse electrical current.
- Wet cells
- Dry cells
- Thermal cells