Alternative Ways to Store Power | What Causes Global Warming

Posted by Sarah Green on December 21st, 2011 filed in Global Warming

Electricity is usually generated at a level that meets expectations, as it is difficult to store surplus energy. Nonetheless it is possible to store reduced quantities of energy for personal and domestic uses. Batteries and fuel cells both produce electricity by using electrochemical reactions. Flywheels store up energy as they spin.

The battery

A convenient store of energy is the electric cell or battery. These are used each day to power torches, radios, toys and lots of other gizmos. The most common form of battery contains carbon and zinc separated by a solution of ammonium chloride. When the battery is attached to an electric circuit, its stored chemical power is changed into electric energy. The battery continues to supply an electrical current until all the chemicals have reacted with one another. Then, the battery is said to be ‘flat’. Batteries comprising nickel and cadmium (Nicads) can be recharged by passing a tiny electrical current thru the battery for one or two hours. This makes them last much longer.

Flywheels

Space stations use solar generating panels and fuel cells as their energy source. This energy is then stored in batteries. These batteries are large and expensive and need to be replaced each 5 years. But new space stations and satellites may use flywheels to store the energy. These can last as long as 20 years. Flywheels are employed in engines, but now scientists are designing far more efficient versions. When energy is used to spin a flywheel, the energy is converted to kinetic energy. The flywheel stores the energy mechanically in the form of kinetic energy. The quicker the flywheel spins, the more energy it stores. This energy can be converted to electricity. The new flywheels will be as small as just fifteen centimetres across, and made of highly strong, yet lightweight, materials. They will spin up to 600,000 times each minute, and can store 8 times more energy than a battery of the same mass.

Fuel Cells

It is possible that in the future, automobile engines, batteries in PCs and even power stations may be replaced by fuel cells. Fuel cells date back to 1839, but until fairly recently, only the US National Aeronautics and Space Administration (NASA) used them.

All fuel cells are energy converters, and work on identical elementary principle. They have two electrodes separated by an electrolyte, a substance that conducts electricity. A fuel like hydrogen enters at one electrode and oxygen enters at the other. They undergo a reaction, which produces an electrical current. When the fuel is hydrogen, the only waste product is pure water.

Fuel cells have many advantages. They convert energy far more efficiently than standard power sources: for instance, a fuel cell is 2 times as efficient as a car petrol engine and produces nearly no pollution. Furthermore, they don’t contain moving parts, so do not produce any noise or vibration. An operating fuel cell is therefore extraordinarily quiet and doesn’t suffer from wear. But there are a bunch of problems to overcome. Currently, fuel cells are awfully high-priced, though this is due to the fact that only tiny numbers are being manufactured. The price will fall once big quantities are produced. There are problems of reliability with some fuel cells. In addition, some bigger fuel cells have a poor power to weight and volume proportion. This means that for their weight or volume, they produce comparatively small amounts of power.

Sarah Green is an environmental campaigner, activist, and robust disciple of being energy self-sufficient. In her free time, she reports on alternative DIY energy blueprints and kits, for example the ben ford homemade energy download.