Worlds proven oil reserves are1200 billion barrels Source : BP Statistical Review of World Energy 2007
However, the world’s consumption of oil continues to grow
Million Barrels of Oil a Day 3.0 90 Annual Consumption 88 2.5Annual growth Rest of the 86 2.0 World 84 1.5 82 USA 80 1.0 78 0.5 China 76 74 0.0 72 -0.5 70 2000 2001 2002 2003 2004 2005 2006 2007 2008
With a world oil consumption growth of 1% per year …
wil l be ser ves an l re th the oi nless di rs… ste auexh 0 y e a 4
• Wind Energy systems• Illustrate key considerations for Wind Energy
Wind Turbine Description• Components – Rotor Schematic of a Horizontal Axis Wind Turbine – Gearbox – Tower – Foundation – Controls – Generator• Types – Horizontal axis • Structure turns rotor into wind – Vertical axis • Less common
Utilisation of Wind Energy• Off-Grid – Small turbines (50 W to 10 kW) – Battery charging – Water pumping• Isolated-Grid – Turbines typically 10 to 200 kW – Reduce generation costs in remote areas: wind-diesel hybrid system – High or low penetration• Central-Grid – Turbines typically 200 kW to 2 MW – Windfarms of multiple turbines
Wind Resource• High average wind speeds are essential – 4 m/s annual average is minimum – People tend to overestimate the wind – Wind speed tends to increase with height• Good resource – Coastal areas – Crests of long slopes – Passes 1 MW Turbine Power Curve 1,200 – Open terrain 1,000 – Valleys that channel winds Power (kW) 800• Typically windier in 600 – Winter than summer 400 200 – Day than night 0 0 2 4 6 8 10 12 14 16 18 20 22 24 Wind speed (m/s)
Conclusions• Wind turbines provide electricity on and off grid world- wide• A good wind resource is an important factor for successful projects• Availability of production credits or Greenpower rates are important for on- grid project
How Nuclear Power Work July 2008 : Around the World, 430 operating nuclear power plants that provided 15 % of electricity in 2007. Leading countries’ electricity which depend on nuclear power : France : 77 % Lithuania : 65 % United States : 20 %
Nuclear Fission Uranium is a common element on Earth. The splitting of an atom releases an incredible amount of heat and gamma radiation, or radiation made of high-energy photons. The decay of a single U-235 atoms releases approximately 200 MeV ( million electron volts ).
Inside a Nuclear Power Plant1st step : Control the energy given off by the enriched uranium and allow it toheat water into steam.2nd step : The pellets are arranged into long rods, and the rods are collectedtogether into bundles.The uranium bundle acts as an extremely high-energy source of heat. It heatsthe water and turns it to steam. The steam drives a turbine, which spins agenerator to produce power.
Outside a Nuclear Power Plant Extra precautions are required as the source can emit harmful levels of radiation. A concrete liner typically houses the reactors pressure vessel and acts as a radiation shield. The steel containment vessel serves as a barrier to prevent leakage of any radioactive gases or fluids from the plant. An outer concrete building serves as the final outer layer, protecting the steel containment vessel. These secondary containment structures are necessary to prevent the escape of radiation/radioactive steam in the event of an accident.
Pros and Cons of Nuclear Power Plants Advantage : it does not depend on fossil fuels. Disadvantage : Transporting nuclear fuel to and from plants poses a contamination risk. When something goes wrong, the situation can turn catastrophic. The Chernobyl disaster is a good recent example. In 1986, the Ukrainian nuclear reactor exploded, spewing 50 tons of radioactive material into the surrounding area, contaminating millions of acres of forest.
Turning Tides into Usable Energy• Ebb generating system• A dam (barrage) is built across the mouth of an estuary.• Sluice gates allow incoming tides to fill the basin.• As the tide ebbs, the water is forced through a turbine system to generate electricity. http://www.acre.murdoch.edu.au/ago/ocean/tidal.html
Types of TurbinesBulb turbine used at La Rance tidal plant on the Brittany coast in France http://www.acre.murdoch.edu.au/ago/ocean/tidal.html http://www.unesco.org/courier/1998_08/photoshr/33.htm
Turbines, cont. Rim turbine used at Annapolis Royal in Nova ScotiaTubular turbine proposed for use in the Severn tidal project in Great Britain http://www.acre.murdoch.edu.au/ago/ocean/tidal.html
Other Possibilities • Tidal Fences • Completely blocks a channel so as the tide rises, water is forced through the styles to turn them. • Can be used between islands or between a mainland and an island as opposed to only across the mouth of a confined bay.
Turning Waves into Usable Energy• Oscillating water column• Incoming waves force air up column to turn the turbine• Outgoing waves suck air down column to turn the turbine
Advantages Abundant (estimated that it could produce 16% of worlds energy.)• Pollution free (except during construction)• Relatively consistent (unlike wind that is inconsistent and is highly concentrated in certain areas depending on the topography.)• Water is a free resource http://www.geology.wisc.edu/~pbrown/g410/tidal/tidal.html http://www.hawaii.gov/dbedt/ert/wavereport/wave.pdf
Disadvantages• Disturbance/Destruction to marine life (effect wave climate that effects shallow/shore plant life)• Expensive to construct (estimated 1.2 billion dollars.)• Reliability ( have not been around long so we do not know long-term reliability is.)• Recreational costs (visual impact, sport fishing, swimming, etc.)• Cost of Maintenance Higher• Power transmission from offshore facilities harder• Power quality (waves fluctuation) http://www.geology.wisc.edu/~pbrown/g410/tidal/tidal.html http://www.hawaii.gov/dbedt/ert/wavereport/wave.pdf
Why ALGAE? • Does not compete with agriculture • High yield per acre •Contains no sulphur therefore no SO2 emissions •Non toxic and highly biodegradable •Does not require soil for growth •Uses as little as 30cm of water per year per hectare (open pond system) •Adaptable anywhere even at great distances from water •Abatement of CO2 – carbon neutral
Oil yield per hectare of microalgae significantly exceeds other common oil sources such as soya and rapeseed33 times Oil yield from algae compared to soya and rapeseed 88 timesmore than more thanrapeseed 40000 soya 35000 Litres of oil produced per hectare 30000 39 500 25000 39 500 20000 PBR* 15000 10000 5000 1190 1 190 446 448 0 Soya Rapessed (oil) Micro Algae *PBR – Photo Bio-Reactor
Adaptability to developing countries – other key factor requirementsAlgae production with Photo Bio-Reactors (PBR) More suitable for Higher Income Countries (due to higher start-up costs)Algae production with MBP (Microalgae Biofixation Process) More suitable for Lower Income Countries (due to lower start-up costs)
Photo Bio-Reactors?•Using Photo Bio-Reactors is expensive but it is a State of the Art Technology, it produces higher yields than other systems.•However, Development and Processing costs are still quite high and perhaps not suited yet for developing countries.
Microalgae Biofixation Process – with wastewater
Open pond wastewater has demonstrated productivities of 100 tonne/ha/yrtonne per hecatre per year.
Powering the Future• We cannot simply rely on coal and oil for they are near to extinction.• Other sources like solar, wind, nuclear, tidal and biomass are emerging and we should encourage their usage for our environment, for us and for the future of mankind.