3.4 Energy and water resources

FIY the syllabus only asks for the significance of renewable and non renewable and the siting of 3 types of power station but I’m going to add a little bit more to that.

Types of resources

• Non-renewable resources: These are finite. Fossil fuels were initially produced by photosynthesis. In theory they are renewable, but it takes millions of years for them to form. E.g. coal, oil, gas, (uranium).
• Renewable resources: These are continuous e.g. solar, wind, water, geothermal. They are therefore sustainable.

Non-renewable resources:

Fossil fuels (coal, oil and natural gas) used mainly by MEDCs

Uranium for nuclear energy

Fuel-wood non-commercial source of energy in MEDCs but important in LEDCs; women have to walk long distances each day to collect wood. They cook over open wood fires or wood burning stoves.

Renewable energy supplies:

-reduce dependence upon fossil fuels

-alleviate the world’s energy crisis

                     -offer opportunities for the development of alternative energy sources

                     -they do not pollute

                     -they do not add to Global Warming

                     -the source lasts forever

Renewable energy supplies are:

-geothermal

-wind

-solar

-bio fuel (since photosynthesis equals the amount of CO₂ from combustion)

-hydroelectric

-tidal

Thermal power stations:

·      In a thermal power station, fuel (coal or natural gas) is burned in a boiler to convert water to steam.

·      The high-pressure steam is directed into a turbine, which turns the turbine shaft.

·      This shaft, connected to an electrical generator, produces electricity as it turns.

·      A condenser converts the spent steam from the turbine back to water that is reused in the boiler.

·      The condenser cooling water comes from the reservoir and is returned for reuse.

They need:

·      A large area of flat land

·      A water source

·      A rail link

·      Isolated area for nuclear

·      Cooling towers

Positioning a power station (the 3 you have to know):

·      Heavy precipitation (relief rainfall) over high mountains

·      Snow and glaciers provide spring water

·      Large drainage basin traps more water

·      Natural glacial lake or reservoir provides constant supply of water

·      Impervious rock prevents water infiltration = surface runoff

·      Steep-sided glaciated valley helps dam construction, water travels faster

·      Site of former waterfall provides a head of water

·      Nearby industrial and domestic demand

·      Small surface area = less evaporation

Resource	Advantages	Disadvantages
Coal	Lasts 300yrs, now become more efficient, needed to make coke	Cost of production high, produces lot of GH gases, dangerous, open cast = visual pollution, costly to transport, acid rain
Oil	More efficient than coal, easier to transport, diversity of uses, petro-chemicals	Lasts only 50-70yrs, oil spills, releases GH gases, prices fluctuate, refineries use lot of space, acid rain
Gas	Cleanest of fossil fuels, cheaper than oil, easy to distribute	Releases methane, explosive, prices fluctuate, acid rain, GH gases.

Water uses:

-Agriculture: to water the plants etc.

-Domestic: cooking, cleaning and drinking

-Industrial: heated to make steam in order to turn turbines, and for cooling down reactors