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When will fossil fuels finally run out? What is the technical potential for renewable energy resources?. Dr. Stas Burek School of the Built and Natural Environment Glasgow Caledonian University Scotland, UK. Fossil Fuels What can historical trends tell us? Renewable energy
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When will fossil fuelsfinally run out?What is the technical potential for renewable energy resources? Dr. Stas Burek School of the Built and Natural Environment Glasgow Caledonian University Scotland, UK
Fossil Fuels • What can historical trends tell us? • Renewable energy • 13,500 times more solar energy than commercial energy consumption • Why is there an ‘energy crisis’?
How much does energy cost? • Cost of electricity (€/kWh) • Cost of gas, oil (€/kWh, €/GJ) • Cost of petrol (€/litre) 0.12 €/kWh 0.05 €/kWh 1.10 €/litre 0.13 €/kWh
How much does personal energy cost? • Rate of work (W) • Energy used for work (kWh/time) • Earnings (€/time) • Cost of personal energy (€/kWh) 200W 0.2 kWh/hour 8kWh/week (40 hours) 5 €/hour (200 €/week) 25 €/kWh
Fossil fuels • ‘Oil will never run out’? • Reserves-to-production ratio (R/P) • Proved reserves: • ‘those quantities that geological andengineering information indicates with reasonable certainty can be recovered in the future from known reservoirs under existing economic and operating conditions’ • Ultimately Recoverable Reserves
Historical data • Assume exponential growth • Annual energy consumption an = a0.rn • Cumulative energy consumption
Future depletion date • Reserves at the start of 1985 667.0 x 103 Mtoe • Consumption in 1985 a0 = 6412 Mtoe • Reserves at the end of 2007 754.6 x 103 Mtoe • Total consumption between 1985 and 2007 (inclusive) an = 178.5 x 103 Mtoe (n = 22) • Cumulative reserves since the start of 1985 Sn = 933.1 x 103 Mtoe (n = 22) • Reserves ratio (1985 – 2007) 1.40
Prospects for fossil fuels • Reserves-to-production ratios • Oil 40 years • Gas 65 years • Coal 155 years • ALL fossil fuels 77 years • Need to find 1.3% reserves each year • Within the uncertainty limits of reserves estimates?
Fossil fuels: Current trends • Ultimate depletion date • ALL fossil fuels 52 years • Since 2000 annual increase has fallen below 2% only twice • For 2% annual increase • Need to increase cumulative reserves by 3% each year • Only two years since 1995 that reported reserves have risen by more than 2%
New reserves • Beware mis-reporting! • e.g., Iran • ‘Large’ finds are actually quite small • Technological development needed • e.g., Canadian tar sands • e.g., methane hydrates
Alternatives to fossil fuels • Use less energy! • Energy efficiency • Reducing unnecessary activities • Economic development needs • Nuclear energy • Heading for the same crisis in the future? • Renewable energy
Hydropower • Water cycle: 3106 times fossil fuel use • Total theoretical capacity 3TW • 60% of fossil fuel consumption • Current contribution 707 Mtoe • 7.2% of fossil fuel consumption • Maximum economical capacity 0.6TW • 12% of fossil fuel consumption
Current status • Three Gorges Dam • 22,500 MW • 84.7 TWh per year (19.3 Mtoe) • 0.23% of fossil fuel consumption • Need another 430 similar schemes to replace fossil fuels
Wave energy • Up to 1000 kW/m • Assume 50 kW/m potential • Need 100,000 km of wave devices to replace fossil fuels • 2½ times the Earth’s circumference • 750 TWh (170 Mtoe) per year economically recoverable • 1.73% of current fossil fuel use
Wind energy • 93,800 MW installed capacity worldwide • 100m diameter, 5MW rated output • To replace fossil fuels: • One tenth of the Earth’s surface • Average windspeed 5m/s • 150m diameter turbine every 2.5 km2
Solar photovoltaic • Currently 25,000,000m2 (25km2) PV cells worldwide • In order to replace fossil fuels • Areas of high solar availability (6kWh/m2 per day) • 350,000 km2 required • 4% of the Sahara Desert • 14,000 times current capacity • PV manufacture and electricity transmission issues
Biomass • Solar energy to photosynthesis 7 times annual fossil fuel usage • To replace fossil fuels: • 14% of the Earth’s surface • 46% of global land area • Conversion efficiency of plants ~1-2%
Conclusions – fossil fuels • R/P ratio for ALL fossil fuels 77 years • New reserves needed 1.3% of current reserves each year • Current trends: ultimate depletion date 52 years • New reserves needed 3% each year of current reserves to maintain 2% annual increase • Uncertainties in estimating reserves • Uncertainties in reported data
Conclusions - renewables • Some renewable technologies could replace fossil fuels ... • ... but would need massive and rapid expansion • Potential for new energy giants • Small-scale developments • Mix of technologies • Environmental impacts • NO ‘SILVER BULLET’!
Finally... Glasgow Caledonian University MSc Energy and Environmental Management MSc Waste Management MSc Sustainable Energy Technology www.gcal.ac.uk
Thank you Any Questions? Dr Stas Burek School of the Built and Natural Environment Glasgow Caledonian University Scotland, UK