Population and Resources A2 Geography

Population and Resources

• -Nuclear energy

Nuclear Energy

• Facts- Provides over 11% of the world's electricity
• -Seen as continous, reliable source of energy without CO2 emissions
• -Over 435 operable nuclear power stations in 31 countries
• UK- 16% nuclear
• -19 reactors on 10 different sites
• -plans for 2025 are 25%
• -In June 2011 8 new sites were chosen for plants across the UK
• -UK pro nuclear energy- coalition government announced nuclear would play a large roll in the UK's future energy mix. Nuclear is low carbon, affordable, dependable, and safe. New nuclear power stations could also reduce the UK's greenhouse gases by 80$.
• Changes over time- The 1986 Chernobyl disaster changed peoples opinions on nuclear, to that it is dangerous.Following this there was a global decline in interest with exceptions such as Japan.
• Japan- LEad the way on nuclear power since 1970s, provides 30% of their electricity, perceptions on nuclear were changed globally resulting in research and investment into the source- green agenda.
• However, 2011 Fukishima disaster highlighted risks of nuclear and not all countries are convinced by it.
• Uranium- Canada and Australia account for about half of the world's known usable reserves. We import mainly from these countries as they are a stable source. The price of Uranium can fluctuate a lot but the cost of Uranium is not the main cost involved in the process and so fluctuations don't tend to lead to major changes in electricity price.

Natural Gas

• Facts- Accounts for 21% of world's energy, it consists mostly of methane, drilled onshore and off shore.
• Onshore- advancements in drilling allow for horizontal drilling which can reach gas reserves which were previously not feasible.
• Offshore- drilling ships and rigs.
• UK- 40% of UK energy, gas from a wide range of sources which reduces dependency (North and irish seas production, pipielines from Europe and Norway, Liquified natural gas shipping in from around the world)
• Gas from the North and Irish seas provides around 40% of gas supplies, however these fields are now in decline and wee are importing from abroad.
• Changes over time- 1990's Dash for Gas- why?- High reserves, easier and cheaper to extract, cleaner than coal, better technology introduced has increased efficiency.
• Better technology- 1) combined cycle gas turbine plant (CCGT)
• -1st plant built in 1991, combines gas turbines and steam turbines to produce energy more efficiently, gas generation accounting for 40% of electricity demand.
• 2) Combined heat and Power (CHP) plants
• different to CCGT that not only generate electricity but also heat that is used in industrial processes, the majority of these plants are located adjacent to industrial sites.
• 3) LNG

Fracking and Shale Gas

• Also classified as a natural gas- trapped within shale rock.
• Extracted from shale rock using fracking- drill and inject fluid into the rock until it is pressurised and fractures releasing the natural gas.
• Shale rock is very common globally making up 35% of the earth's natural rock, the process of fracking was used often in the oil industry in the 19th century.
• Ineos to invest £640 million in UK shale gas exploration.
• Shale gas being explored near Immingham.
• Issues- Many groups against the risk of fracking, such as risk of earthquakes and aquifer contamination from methane.

Wind Energy

• UK- Renewables produce around 7% of the UK's electricity, with wind producing around 3% of the UK's electricity. EU targets hope to increase renewables to 30% by 2020. From 2020 renewable enrgy will continue to be a big part of the strategy to reduce carbon emissions, to achieve this a range of technologies will need to be used such as onshore and offshore wind farms (biomass powerstations and hydropower systems).
• Changes over time- First wind turbine was in the 19th century and was about 12 kw, first MW turbine was in 1940' and was about 1mw. Higher on the agenda since the 1990s- wind farm developments onshore/ offshore- inline with the Kyoto protocol (1995).
• Wind farming very big on British west coast due to Atlantic winds.
• UK development offshore wind farms- UK government targets- Build 33 GW of offshore wind farms by 2020, supply 15% of all UK needs.
• New Technology- Increased efficiency
• Larger turbines= higher outputs
• These machines are designed for the offshore wind conditions eg- Vestas has developed a new 8MW wind turbine with 80m blades, Siemens, Samsung and MHI Sea Angel also developing.
• Thames estuary wind farm - proposed site of world's largest offshore wind farm, if built would feature 341 turbines, could generate upto 1000MW of electricity , enough to supply the demand of around 750,000 homes per year. #
• Popularity of wind in the UK- Uk's 6th largest producer of wind in world, polling of public consistently shows support for wind power in the UK, nearly 3/4 of the population agree with its use.
• Issues- 1) world steel prices- world price of steel has increased greatlt in recent years, as has the price of turbines- suppliers such as siemens are currently at capacity, as a result the estimated cost of the plan has risen from £40bn to £80bn.
• 2) security over investment- Shell (one of the original backers) has pulled out- due to rising steel prices, marginal operating returns and problems with the supply of winds turbines and support infrastructure.

Biomass, Biofuel and Biogas