1. Nabil Reza

2.  Off-peak electricity is used to power a motor/generator that drives compressors to force air into an underground storage reservoir.  When the demand for electric power peaks, The compressed air is returned to the surface, and is fed into a gas turbine, allowing the turbine to produce electricity more efficiently.  Natural Gas is burned to preheat air.  Storage reservoirs can be large underground caverns, depleted wells, or aquifers.

4.  CAES power plant system can achieve >85% reductions in fossil fuel use.  Can achieve over 80% reduction in CO2 output  Adiabatic Compressed-Air Energy Storage recovers the heat that emerges during air compression.  The stored thermal energy replaces the need for natural gas, causing the entire system to run on renewable power alone

5. http://www.youtube.c om/watch?v=K4yJx5y TzO4

7.  280 MW plant in Hunthorf, Germany - been active since 1978  110 MW plant at McIntosh, Alabama - operating since 1991

8.  Insatallation cost - Depending on hours of storage, $750/kW to $1,200/kW.  Running cost at about 10.5 cents/kWh  Diabatic storage efficiency is around 55%  70% for adiabatic CAES

9.  CAES systems can be used on very large scales. CAES is ready to be used with entire power plants.  Fast start-up time – 9 min, compared to 20 min for conventional combustion turbine  Helps solving peak load crisis

10.  A flywheel is a flat disk or cylinder that spins at very high speeds, storing kinetic energy.  When required, the flywheel then delivers rotational energy to power an electric generator until friction dissipates it.

11. http://www.youtube.c om/watch?v=eCtlfj4k MJs

12. E f = (1/2) x I x ω 2 where E f = flywheel kinetic energy (Nm (Joule), ft lb) I = moment of inertia (kg m 2, lb ft 2 ) ω = angular velocity (rad/s) I = k x m x r 2 where k = inertial constant m = mass of flywheel (kg, lb) r = radius (m, ft)

13.  Tensile strength - the stronger the disc, the faster it may be spun, and the more energy the system can store.  Energy storage efficiency - 50% for mechanical bearings, 85% for magnetic bearings

14.  Beacon Power - 20 MW plant in Pennsylvania  Installation cost - around $1,500 per kilowatt

15.  Little affected by temperature fluctuations,  Take up relatively little space  Have lower maintenance requirements than batteries  Very durable.

16.  Storage devices that convert Chemical Energy to Electrical Energy  Batteries are made up of cells, containing a chemical called an electrolyte.  Each cell has two electrically conductive electrodes immersed into its electrolyte, one releases electrons into the electrolyte, and the other absorbs them.  When an electrical device is connected to the electrodes, an electrical current flows through it and provides electric power for its operation.

17.  Lead-Acid  Lithium-ion  Lithium polymer  Nickel metal hydride  Sodium sulfur  Flow Battery

18.  Electrolyte is stored in external containers and circulated through the battery cell stack as required.  Flow batteries use two liquid electrolytes that react when pumped through a cell stack. The battery is broken down into a cell stack and two large electrolyte tanks.  As the electrolyte flows past a porous membrane in each cell, ions and electrons flow back and forth, charging or discharging the battery.

19. http://www.youtube.c om/watch?v=0Uk0GQ Ngtqg

20.  The active materials in a NaS battery are molten sulfur as the positive electrode and molten sodium as the negative.  The electrodes are separated by a solid ceramic, sodium - alumina, which also serves as the electrolyte.  During Charge and Discharge cycle, electrons flow from Na to S and vice versa through an external circuit.

22.  Flow Batteries ◦ 250 KW installation in Castle Valley, Utah  NaS Batteries ◦ 4 MW installation for Texas Power Grid ◦ 270 MW installation in Japan by Tokyo-based NGK Insulators

23. ParameterZn/BrVBNaS Rated Output (MW)10 Efficiency0.60.750.77 Unit cost for power electronic ($/KW) 312.5 Unit cost for storage units ($/KWH) 350750400 Unit cost for balance of plant ($/KWH) 777 Fixed O & M Cost ($/KW) 6.26

24.  Electricity storage can be deployed throughout an electric power system— functioning as generation, transmission, distribution, or end-use assets.  Sometimes placing the right storage technology at a key location can alleviate a supply shortage situation, relieve congestion, defer transmission additions or substation upgrades, or postpone the need for new capacity.

25.  http://www.rwe.com/web/cms/en/183732/rwe/innovation/projects- technologies/energy-storage/compressed-air-energy-storage/ http://www.rwe.com/web/cms/en/183732/rwe/innovation/projects- technologies/energy-storage/compressed-air-energy-storage/  http://thinkprogress.org/climate/2009/08/31/204578/clean-energy-storage- wind-solar/?mobile=nc http://thinkprogress.org/climate/2009/08/31/204578/clean-energy-storage- wind-solar/?mobile=nc  http://www.pangeaexploration.com/compressed_air_energy_storage.htm http://www.pangeaexploration.com/compressed_air_energy_storage.htm  http://www.dg.history.vt.edu/ch2/storage.html http://www.dg.history.vt.edu/ch2/storage.html  http://www.ngpowereu.com/article/flywheel-power-and-energy-storage/ http://www.ngpowereu.com/article/flywheel-power-and-energy-storage/  http://www.greentechmedia.com/articles/read/beacon-powers-bankruptcy- autopsy http://www.greentechmedia.com/articles/read/beacon-powers-bankruptcy- autopsy  http://spectrum.ieee.org/energy/the-smarter-grid/batteries-that-go-with-the- flow http://spectrum.ieee.org/energy/the-smarter-grid/batteries-that-go-with-the- flow  http://www.electricitystorage.org/technology/storage_technologies/batteries/soi dum_sulfur_batteries/ http://www.electricitystorage.org/technology/storage_technologies/batteries/soi dum_sulfur_batteries/  http://www.eia.gov/todayinenergy/detail.cfm?id=6910#tabs_ElecStorage-1 http://www.eia.gov/todayinenergy/detail.cfm?id=6910#tabs_ElecStorage-1  http://www.nrel.gov/learning/eds_batteries.html http://www.nrel.gov/learning/eds_batteries.html  http://www.nrel.gov/learning/eds_compressed_air.html http://www.nrel.gov/learning/eds_compressed_air.html  http://www.nrel.gov/learning/eds_flywheels.html http://www.nrel.gov/learning/eds_flywheels.html