ELECTRICITY

Generating electricity

Distributing electricity

DC vs AC

ELECTRICITY PRODUCTION

Electricity can be generated from sunlight using photovoltaic cells grouped together in a solar panel, or through electromagnetism inside a generator. In the second case, power is needed to turn the turbines moving electromagnets; this power can come from:

water

wind

steam

FOSSIL FUELS

• Non-renewable sources
• They are formed from the remains of plants and animals
• They are buried underground or under the sea
• they are extracted through mining and drilling
• Advantages = cheap
• Disadvantages:
• many of the supplies are in parts of the world which are politically unstable --> it’s risky for countries to be dependent ON imports from these areas

DISTRIBUTING ELECTRICITY

Electricity is distributed from power stations along overhead wires called transmission lines, supported by pylons

When electricity reaches the areas where it will be used, there are substations containing step-down transformers which reduce the high voltage to levels suitable for the different types of consumer. This because too high voltages would be much too dangerous for homes and offices

As electric current moves along the transmission lines, it gradually loses energy because of resistance from the metal in the wires. This problem can be solved by transmitting the current at high voltage. In fact, high voltage means less current needed, therefore, less energy lost.

cheaper than laying underground cables

DIRECT AND ALTERNATING CURRENT

Alternating current flows for a fraction of a second first in one direction and then in the other.

Direct current is a current of electrons flowing in one direction only.

Electricity is carried from the panel throughout the home thanks to the wiring system

SERVICE PANEL

It’s the central distribution point for delivering electricity to your home switches, outlets and appliances. It’s also where you turn the power off when necessary.

protect the wires in the circuits from overheating. They are designed to stop the electrical current if it exceeds the safe level

FAULTY OUTLETS

Faulty outlets are unusually warm to touch, discoloured or make cracking, sizzling or buzzing noises. It may indicate an unsafe wiring condition

wind power

It’s a form of renewable energy that harnesses / uses the power of the wind to generate electricity. The force of the wind rotates the blades of mills, for example, or wind turbines

Water energy

It’s the energy produced from water. Dams are used to increase the power of rivers to turn the turbines in hydro-electric stations

Steam power

It’s the power produced by boiling the water through fossil fuels, nuclear fission, solar furnaces, biomass or geothermal energy.