Types of Energy Storage Technologies Considered for Financing

Batteries (Flow batteries, Lead Acid, Li-Ion):

Electrical energy is stored for later use in chemical form.  Existing battery technologies are being improved and new battery technologies are becoming available. Batteries (“groups”; from artillery guns) of cells are used separately or in a case containing several cells; a 12V car battery has six 2V cells inside the case. Various cell chemistries are used: Lead-acid; Nickel-cadmium; Lithium Nickel-metal hydride, Zinc-air

Thermal Storage

• Air conditioners create ice at night, when power rates are low.  The stored ice then runs a cooling system during the afternoon when power rates are highest.
• Flywheels
• Flywheels convert electrical energy to kinetic energy and then back again rapidly.  Ideal for power conditioning and short-term storage.
• Compressed Air
• Electricity is used to compress air into storage tanks or a large underground cavern. The compressed air is used to spin turbines when electricity is needed.
• Pumped Hydro
• Excess electricity is used to pump water uphill into a reservoir. When power is needed, the water can run down through turbines, much like a traditional hydroelectric dam.