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Overview. The Atmosphere – Greenhouse gases CO 2 Emissions Across the Globe Consequences of Climate Change on Atmosphere World Energy Status Impact of Climate Change on Power Plants Advanced Thermal Power Plant Technologies. Atmosphere - Carbon Cycle.
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Overview • The Atmosphere – Greenhouse gases • CO2 Emissions Across the Globe • Consequences of Climate Change on Atmosphere • World Energy Status • Impact of Climate Change on Power Plants • Advanced Thermal Power Plant Technologies
Atmosphere - Carbon Cycle • Ocean inventory of carbon 3800 Gt - C • Terrestrial biosphere inventory is 2000 Gt - C • Total inventory of carbon in atmosphere is equal to 780 Gt-C
The Atmosphere Global temperature rise is observed over last few decades. Global warming due to greenhouse gas
Greenhouse Gases What is greenhouse effect? When sun energy hits the earth, the earth in turn reflects that energy back toward the sun . These greenhouse gases absorb that energy and retain with them.
Greenhouse Gases • What are the green house gases? • CO2, CH4, N2O, Water vapour, Ozone and other fluorides • CO2 is one of the greenhouse gas • CO2 is the only parameter correlated well with increase in global temperature.
Greenhouse Gases – Life Time http://lwf.ncdc.noaa.gov/oa/climate/gases.html
Is Greenhouse Gas is Boon or Bane? • Boon, if manmade emissions are within acceptable limit • CO2 emissions raised by 53% between 1970 to 2011I (IPCC). 382 383 384 385 386 387 388 389
CO2 Thermodynamics in Atmosphere • Out of total ocean carbon inventory, 92% is bicarbonate ions, 3.3% carbonate ion, dissolved CO2 is 2% • Rise in atmospheric CO2 concentration increases CO2 uptake by ocean • Reduction of atmospheric carbon inventory (an estimated 1/3rd of CO2 taken by ocean in the period 1990 to 2005). • An increase in surface ocean acidity. CO2 + H2O <---> H+ + HCO3- H+ + CO32- <---> HCO3-
CO2 Emissions • In 2010, anthropogenic CO2 emissions are around 33 Gt where as in 1970 15.3 Gt
CO2 Emissions – Global warming • 82% of the total global warming contributed by anthropogenic CO2 emissions (Raghuswami et al., 2006).
CO2 Emissions - Indian Scenario Gt • 2/3 of world CO2 emissions comes from top 10 countries • India stands 3rd among Top 10 CO2 emissions list IEA Statistics (2009)
Sources of CO2 Emissions • Power stations - Electricity generation • Other energy industry – Steel, Cement, Fertilizer, Glass, etc • Transportation – bikes, cars, buses, trains, aero planes, etc • Domestic – cooking • Commercial and public services - • Agriculture and forestry fuel use – Due to land usage
World CO2 Emissions by Sector • Other includes commercial/public services, agriculture/forestry, fishing, energy industries other than electricity and heat generation
Consequences Due to Climate Change • CO2 emissions may rise between • 470 to 550 ppm by 2050 • 540 to 860 ppm by 2100 • Global temperature may rise between 2 to 60 C by 2100
Consequences Due to Climate Change • For each 0C rise in global temperature may lead to • 5-10% changes in precipitation • 5-10% changes in stream flow across many river basins • 15% decreases in the sea ice across the Arctic Ocean, • 5-15% reductions in the yields of crops
Estimated Sea Level Rise • Due to rise in global warming sea level rise • Water swelling • Melting of glaciers • Rise in water level is a threat to sea side cities
Predicted Sea Level Rise • India has coastline of 7517 km IPCC AR4, 2007
Submerging of Small Islands • In the past two decade 4 islands flooded permanently • Bedford (or Suparibhanga), • Lohachara, • South Talpatti Island and • Kabasgadi • Only Lohachara has around 7000 inhabitants Photo: 20th March 2011 www.privateislandnews.com
Consequences of Global Warming www.google.images.com
World Energy Status > 80% of the world’s energy demand is met by fossil fuels Mtoe
World Electricity Generation In 2010, ~67% world’s electricity obtained from fossil fuel • Distribution of renewable energy resources
Indian Power Generation • India’s total power production capacity (June, 2012) is 206.45 GW • 56.8% production by using coal as fuel www.powermin.nic.in
Power Plant Emissions • 50, 000 power plants exists world wide • 41% of the total CO2 emissions comes from electricity generation (IEA, 2011). • World energy may rise 53% by 2035 (IEO 2011).
Reserves of Fossil Fuels • At current rate of fossil production/consumption (World Coal Association) • Coal reserves last for approximately 118 years • Proven oil reserves last for 46 years • Gas reserves last for 59 years
Different kinds of Power Plant • Types of power plants • Coal fired power plants • Gas fired power plants • Oil fired power plants • Possible Pollutants • NOx, SO2, CO, Unburnt HCs, Particulates (fly ash), mercury, and CO2
CO2 Emissions Vs Fuel Marion & Griffin, ALSTOM, NETL report
Lay-out of Coal-fired Power Plant newenergyandfuel.com
Lay-out of Gas-fired Power Plant • It is comparative simple system • Gas turbine is used instead of steam turbine • Pollutants are low • Efficiency is higher • Combined Cycle Power Plant (CCPP).
Emissions and Its Consequences • Short term effects • Acid rains • Less visibility • Pulmonary diseases • Long term effects • Global warming • Sea level rise • Uneven rains
Greenfield Power Plant Design • Identifying energy losses and gains • Detailed heat integration • Optimizing the plant design • Updating with new technology
Fluidized Bed Combustion Technology • For high ash coals • For high sulphur coals • CaCO3 is added • Rankine cycle is used • Moderate fineness of coal is sufficient • Low pollutant emissions
Integrated Gasification Combined Cycle • Higher efficiency & Lower emissions • Combined cycle plant • Rankine • Brayton • Syngas will be fired in gas turbine • BHEL is plan for 182 MWe IGCC plant
HiTAC or MILD or Flameless Combustion • Air is preheat temperature > Auto ignition temperature • Low oxygen concentration in the air • Low NOx emissions • Uniform heat flux
Supercritical Combustion Technology • Based on Steam Pressure and Temperature • Sub-critical • Super critical • Ultra super critical • Pc = 221.2 bar, Tc = 374 0C • Area under the enthalpy curve increases
Advanced Ultra Supercritical Combustion Technology • Supercritical steam power plants • Pc = ~240 bar & • Tc = ~5700 C • Advanced ultra supercritical steam power plants • Pc = ~300 bar & • Tc = ~6000 C