Energy supplyEnergiförsörjning

World energy supply and demand

Energy sources Almost all the energy we use originates

from the sun. The energy reaches us on earth via

radiation. The only energy sources that are not

connected to the sun are:- Nuclear power.- Earth heat.

Bio-fuels Fuel that comes from living organisms. Firewood, charcoal, peat, halm, energy

grass.

PROS CONS

• Easy to use and get • Deforestation

• No special equipment needed

• Land erosion

• Cheap • Desertification

• Greenhouse effect

Hydropower To be able to use water as power source,

inland waters have to be large enough and landscape have to be hilly.

Hydropower plants produce about 24 % of the world's electricity.

PROS CONS

• Renewable energy source

• Affects the eco-system negatively

• Sustainable • Conflicts of interest about who ”owns” water

• Cheap to build

• Clean/no pollution

Oil Biggest energy source in the world. Produces about 35 % of energy in the

world. Raw material for petrol, lighter fluid,

kerosene and plastics.PROS CONS

• Many possible uses. • Oil spills during extraction or transport.

• Easy to transport. • Carbon dioxide emissions• Easy to store.

• Political power tool.

Gas Used to make electricity, as fuel for

buses, and as industrial energy source. Gas reserves will run out in 60 years.

PROS CONS

• Cleanest fossil fuel, producing less carbon dioxide than oil and coal.

• Gas = inflammable Risky transport.

• Political conflicts about pipelines.

Coal Second biggest energy source

in the world. Coal reserves will run out in a couple of

hundreds of years.

PROS CONS

• Cheap. • Coal dust & ashes pollute the air.

• Easy to extract. • Produces carbon dioxide, sulphur dioxide & different heavy metals.

• Easy to store and transport.

Nuclear power In 2012, there were 439 nuclear power

plants in operation in the world. New power plants built in Asia. In Europe and Asia opposite trend.

PROS CONS

• Cheap energy. • Nuclear fuel is dangerous.

• Relatively safe for the environment.

• Danger of nuclear meltdown.

• Nuclear waste is radioactive.

Wind power In 2010 wind energy production counted

for about 2.5% of total worldwide electricity. PROS CONS

• Wind power is totally renewable.

• Wind does not blow consistently or steadily.

• Low ongoing costs. • Noisy.

• Emits no air pollution. • Visual pollution.

Wave energy Making use of the motion energy from

waves. Wave farms

PROS CONS

• Renewable energy source.

• Impact on commercial fishing.

• No air pollution. • Noise pollution.

• Navigation hazards.

Geothermal energy Not connected to the sun. Making use of the internal heat of the globe.

PROS CONS

• Renewable energy. • High installation costs.

• Clean for environment.

• Not easy to transport.

• Reliable, always available.

• Only suitable for regions with vulcanic activity.

Solar energy A direct form of energy.

PROS CONS

• Renewable energy source.

• High initial cost.

• No pollution. • Limited location.

• Long lasting solar cells.

• Unreliable.

• Low maintenance. • Inefficient.