Energy Storage
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Energy Storage

It is not only important to produce energy, but to store it efficiently for later use. If we could "produce" energy without pollution emissions and store it environmentally friendly our world would be a real clean one.

Flywheel

"Any type of heavy disk-shaped object that stores rotational kinetic energy, and is typically supplied by a rotary actuator; a flywheel's efficiency is determined by its inertia which depends on the rotors mass and geometry."

Some automotive manufacturers are working with FES (flywheel energy storage) to impulse their cars instead of internal-combustion motors or chemical batteries. The efficiency of the flywheel depends on three factors:

  1. Losses in the power supply energy when energy is converted.
  2. Losses in power conditioning systems.
  3. The action of friction and drag that causes a loss of energy in the flywheel.

A vacuum is used to reduce the dampening effect of windage and drag, while lubricants and bearing systems minimize the effects of friction.

FES are used in modern power plants to store energy under low demand periods and then extract it during peak hours. Coupled with other energy resources like solar power or the wind, FES systems could provide cheap and environmentally clean power for industrial and domestic use.

Chemical batteries in electric vehicles.

Electrical vehicles (EVs) store electrical energy in a large, rechargable battery. A system controller sends this power whenever the driver pushes down on the accelerator pedal. Recharging is accomplished by plugging the vehicle's charge plug into a 240 or 120 volt charge receptable. Advanced EVs also use regenerative brakes to charge battery while braking instead of generating friction.

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Limited Range: EVs uses lead acid batteries or prototype batteries that have 50 to 100 miles range.
Clean: EVs have no emissions. In the other hand, emissions are generated to produce energy to charge batteries and the lead and acid is really toxic.
Quiet: EV motors emit almost no sound.
Smooth: Acceleration is smooth and seamless and doesn't use transmission.
Home Recharging: The EV can be recharged at home with no need to go to a gas station or similar, getting fully recharged in 4 to 6 hours.

Electric Vehicle internal parts.

Power Electronics: Controls the flow of electricity to charge the battery, impulse the vehicle and control the lighting and power system.
Vehicle System Controller: Shows all critical functions and optimizes the vehicle operation.
Power Protection Center: Control the safety functions.
Battery: Provides the energy.
Drive Motor: It converts electric power into a single speed.

Fuel Cells

Fuel cells converts hydrogen and oxygen into energy with an electro-chemical process. It is cleanest when using pure hydrogen, the cell also works with gasoline, metanol, natural gas or any other hydrogen-rich fuel, achieving bouble the fuel economy of courrent automobiles and cutting emissions in half.

Fuel cells have been investigated to make them work at no so high temperatures to avoid waste of energy and corrosion of the fuel cell parts. There has been developed a fuel cell that works at low temperatures using Hydrogen, but it is very expensive and has only been used in space crafts and other major applications.

The reactions that take effect in a H-O fuel cell are the following:

Anod:  2H (g) + 4OH (ac)   -----> 4H2O (l) + 4e-

Catod: 4e- + O (g) + 2H2O -----> 4OH (ac)

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2H (g) + O (g) -----> 2H2O (l)