Energy Impacts Ecological impacts of energy generation from

Energy Impacts Ecological impacts of energy generation from non-renewable energy sources in global & local scale and probable mitigation measures Prof. R. Shanthini July 01, 2019 Global scale: greenhouse gas emissions, global warming, and climate change Local scale: acid rain, particulate pollution, thermal pollution and related impact, fresh-water exploitation, and altering land use

Water for Energy (Water or Energy) - Hydroelectric power generation - Energy resource extraction, refining and processing - Thermoelectric power plant cooling - Biofuel production World 2005 2020 2035 2050 Population (billion) 6. 29 7. 84 8. 60 9. 44 Energy Consumption (EJ =1018 J) 329 400 465 519 Water for energy (billion m³/year) 1986 2088 2020 Prof. R. Shanthini July 01, 2019 1815 http: //www. worldenergy. org/publications/2849. asp

Water for Energy (Water or Energy) - Hydroelectric power generation - Energy resource extraction, refining and processing - Thermoelectric power plant cooling - Biofuel production Prof. R. Shanthini July 01, 2019

Coal extraction, refining and processing: Acid mine drainage (AMD): - Coal mining activities could expose rocks containing the sulphurbearing mineral pyrite [Fe. S 2]. - When exposed to air and water, pyrite form sulphuric acid [H 2 SO 4] and iron hydroxide [Fe(OH)3] - As water washes through mines, this compound forms a dilute acid, which can wash into nearby rivers and streams. Prof. R. Shanthini July 01, 2019

Coal extraction, refining and processing: Acid mine drainage (AMD): - AMD discharges elevated concentrations of acidity, iron, manganese, aluminum, and sulfate into receiving streams and rivers, depleting the buffering ability of water by neutralizing carbonate and bicarbonate ions that form carbonic acid. - Streams and rivers with low buffer capacity are not able to neutralize the acid load and consequently become acidic. - River Basins degraded by AMD may not be able to support fish communities. Prof. R. Shanthini July 01, 2019 http: //www. sourcewatch. org/index. php/Water_pollution_from_coal

Coal extraction, refining and processing: Mountaintop removal mining (MTR): It involves the blasting off the tops of mountains to reach the coal seams below, with the millions of tons of former mountains pushed into stream valleys. An EPA environmental impact found that 724 miles (1, 165 km) of Appalachian streams were buried by valley fills between 1985 to 2001, and that streams near valley fills from mountaintop removal contain high levels of minerals in the water and decreased aquatic biodiversity. The 2012 Environmental Science and Technology study "How Many Mountains Can We Mine? Assessing the Regional Degradation of Central Appalachian Rivers by Surface Coal Mining" concluded that decades of mountaintop-removal mining in Appalachia may have harmed aquatic life along more than 1, 700 miles of streams in southern West Virginia. Prof. R. Shanthini July 01, 2019 http: //www. sourcewatch. org/index. php/Water_pollution_from_coal

Coal extraction, refining and processing: Coal sludge (or slurry): It is the liquid coal waste generated by washing coal. It is typically disposed of at impoundments located near coal mines, but in some cases it is directly injected into abandoned underground mines. Since coal sludge contains toxins, leaks or spills can endanger underground and surface waters. Prof. R. Shanthini July 01, 2019 http: //www. sourcewatch. org/index. php/Water_pollution_from_coal

Oil extraction, refining and processing: Prof. R. Shanthini July 01, 2019

Oil production at very deep ocean Pressure is over 500 atm Depth drilled by British Petroleum is 5. 5 km (3. 4 mile) below sea level Ocean is black since no sunlight penetrates to these depths Prof. R. Shanthini July 01, 2019

Oil production at very deep ocean 4. 9 million barrels of oil was spilled on the Gulf of Mexico. BP was after 50 millions barrel of oil = 63% of global oil use per day = 20% of global energy use per day Prof. R. Shanthini July 01, 2019

Oil extraction, refining and processing: Oil plume: Evaporation of hydrocarbons in the atmosphere 500 m Water pressure 1000 m Dissolution of gases & hydrocarbons in the water Underwater currents Prof. R. Shanthini July 01, 2019 1500 m

Natural Gas extraction, refining and processing: Hydraulic fracturing or ‘fracking’: Wells are drilled deep into the shale, initially vertically, then horizontally, explosive charges then fracture the rocks, and then a highly toxic mixture of over 500 chemicals, many of them known carcinogens, is pumped under pressure into the rocks, followed by huge volumes of water into which the natural gas then dissolves. Prof. R. Shanthini July 01, 2019 http: //transitionculture. org/2011/04/05/a-film-review-gasland/

Natural Gas extraction, refining and processing: About half of this water is then pumped out again, the gas removed, and the highly toxic water is then, in theory at least, safely disposed of. Prof. R. Shanthini July 01, 2019 http: //www. gaslandthemovie. com/whats-fracking

Natural Gas extraction, refining and processing: In 2005, the Bush/ Cheney Energy Bill exempted natural gas drilling from the Safe Drinking Water Act. It exempts companies from disclosing the chemicals used during hydraulic fracturing. Essentially, the provision took the Environmental Protection Agency (EPA) off the job. It is now commonly referred to as the Halliburton Loophole. Prof. R. Shanthini July 01, 2019 http: //www. gaslandthemovie. com/whats-fracking

Natural Gas extraction, refining and processing: Watch GASLAND http: //vimeo. com/38843993 Prof. R. Shanthini July 01, 2019

Water for Energy (Water or Energy) - Hydroelectric power generation - Energy resource extraction, refining and processing - Thermoelectric power plant cooling - Biofuel production Prof. R. Shanthini July 01, 2019 http: //www. worldenergy. org/publications/2849. asp

Thermoelectric power plant cooling - A typical steam turbine power plant uses a fuel (coal, natural gas, oil or nuclear) to heat water into steam in a steam generator. - Steam generated turns a turbine connected to a generator, which produces electricity. - The steam leaving the turbine is then condensed back into water and pumped to the steam generator again to maintain efficient operation. - Condensing steam into water requires cooling by an external source, which is mostly water (known as cooling water). - Cooling water is often drawn from river or sea, to which warm water is returned (in the once-through cooling systems). Prof. R. Shanthini July 01, 2019 http: //www. favstocks. com/why-power-plants-use-so-much-water-and-what-to-do-about-it/296455/

Steam power plant hot gases superheated steam compressed water Steam Generator Steam Turbine Pump C Condenser saturated water Prof. R. Shanthini July 01, 2019 cooling water Gen saturated steam

Steam power plant with Once-Through-Cooling System hot gases superheated steam compressed water Steam Generator Steam Turbine Pump C Condenser saturated water cooling water Cold water Gen saturated steam Warm water River (sea or some other water source) Prof. R. Shanthini July 01, 2019

Mechanisms used for power plant cooling: • Once-through (open-loop) cooling systems • Recirculating (closed-loop) cooling systems • Dry cooling systems • Hybrid cooling systems Prof. R. Shanthini July 01, 2019 http: //www. ucsusa. org/assets/documents/clean_energy/10 -Things. pdf

Once-through (open-loop) cooling system It takes cooling water (CW) from a water source (rivers, lakes, underground aquifers or the ocean), and circulate it through condenser to absorb heat from the steam entering the condenser. The heat absorbed by CW increases the temperature of CW, and this warm water is discharged back to the local water source. Condenser Condensed water sent back to power plant Cold water Steam from turbine Warm water Water source Prof. R. Shanthini July 01, 2019 http: //www. favstocks. com/why-power-plants-use-so-much-water-and-what-to-do-about-it/296455/

Cooling water withdrawal of once-through (open-loop) cooling systems: coal-fired power plant Nuclear power plant 76 -190 litres/k. Wh 95 -230 litres/k. Wh 1 k. Wh = 1 kilowatt-hour = 1000 Wh Average electricity consumption of a house per day in Sri Lanka = (5 x 60 W)(3 h) = 900 Wh = 0. 9 k. Wh 1 k. Wh Cooling water withdrawal to electrify a house in Sri Lanka 76 – 190 litres per day with coal power plant Average electricity consumption in USA 35 k. Wh/person/day Cooling water withdrawal in USA 2500– 8000 litres/person/day Prof. R. Shanthini July 01, 2019 EPRI [Electric Power Research Institute]. 2002 a. Comparison of Alternate Cooling Technologies for California Power Plants Economic, Environmental and Other Tradeoffs.

California moves to ban once-through cooling Californian regulators have adopted (on 04 May 2010) a policy requiring coastal power plants to phase out the use of oncethrough cooling systems. The policy applies to 19 existing power plants that currently withdraw over 60 billion litres of cold seawater per day from the state's coastal and estuarine waters to cool their turbines and then return the water at higher temperatures. The new regulations require such plants to stop this "oncethrough" practice and install equipment to reduce their impact on marine life. (Over 79 billion fish and other marine species are estimated to be killed each year. ) Prof. R. Shanthini July 01, 2019 http: //www. world-nuclear-news. org/RS-California_moves_to_ban_once_through_cooling-0605105. html

How does the marine life gets affected? - From endangered sea turtles to delicate fish larvae and microscopic planktonic organisms vital to the ocean ecosystem, is sucked into the reactor cooling system (a process known as entrainment). - Discharge water is at 15 degrees C hotter than the sea water. Indigenous marine life suited to colder temperatures is consequently eliminated or forced to move, disrupting delicately balanced ecosystems. - Hot water disturbs the biotope as it causes algae growth and makes the water oxygen-deficient. This can lead to fish mortality and biodiversity disruption. Prof. R. Shanthini July 01, 2019 http: //www. nirs. org/press/02 -22 -2001/1

How does the marine life gets affected? - Warmer ambient water temperatures encourage warm-water species to colonize the artificially maintained warm-water zone. - When the warm water flow is diminished or halted because of maintenance, cleaning, or repair work, these species are often "cold-stunned; " many subsequently die of hypothermia. Prof. R. Shanthini July 01, 2019 http: //www. nirs. org/press/02 -22 -2001/1

Recirculating (closed-loop) cooling system It reuses cooling water with makeup water drawn from water sources. Such systems withdraw comparatively small amounts of water but lose most of it through evaporation. Water vapour Warm water Condensed water sent back to power plant Steam from turbine Cold water Blow down is to release the heavy metals and salts build up in the cooling water. Prof. R. Shanthini July 01, 2019 Fresh (make-up) water supply Cooling tower Blow-down Water source http: //www. favstocks. com/why-power-plants-use-so-much-water-and-what-to-do-about-it/296455/

Recirculating (closed-loop) cooling system Three Mile Island nuclear power plant near Middletown, Pennsylvania, United States Prof. R. Shanthini July 01, 2019

Recirculating (closed-loop) cooling system - alters the local climate Prof. R. Shanthini July 01, 2019

Cooling water withdrawals (and consumption) for power plants: Once-through (open-loop) cooling systems (in litres/k. Wh) Recirculating (closed-loop) cooling systems (in litres/k. Wh) coal-fired power plant 76 -190 2 -2. 3 Nuclear power plant 95 -230 3 -4 Capital cost of the cooling water system low high Prof. R. Shanthini July 01, 2019 EPRI [Electric Power Research Institute]. 2002 a. Comparison of Alternate Cooling Technologies for California Power Plants Economic, Environmental and Other Tradeoffs.

Is there any other ecological damage by cooling water usage in the power plants? - Corrosion inhibitors are used in cooling water. - Cooling water is dosed with biocides and algaecides to prevent growths that could interfere with the continuous flow of water. - Biocides are used in cooling towers to prevent the growth of bacteria which (upon entering human body through inhalation of mist droplets containing the bacteria) may cause Ligionnaires’ disease. - Cooling towers produce quite a lot of noise, caused particularly by the fans and dropping water. If a cooling tower is established too close to a residential area, this may cause noise nuisance. Prof. R. Shanthini July 01, 2019 http: //www. ucsusa. org/assets/documents/clean_energy/10 -Things. pdf

Mechanisms used for power plant cooling (continued): Dry-cooling systems use air instead of water to cool the steam exiting a turbine. Dry-cooled systems can decrease total power plant water requirements by as much as 90%, though adding cost and decreasing efficiency. Prof. R. Shanthini July 01, 2019 http: //www. ucsusa. org/assets/documents/clean_energy/10 -Things. pdf

Mechanisms used for power plant cooling (continued): Hybrid cooling systems use air for cooling most of the time, but can draw on water during particularly hot periods. Prof. R. Shanthini July 01, 2019 http: //www. ucsusa. org/assets/documents/clean_energy/10 -Things. pdf

Thermal Pollution - It refers to the degradation of the quality of a natural water resource caused by increase in its temperature. - Power plants and industries are major contributors to thermal pollution. - Removal of trees along the shore line increases solar incidence and hence warms up the water. Prof. R. Shanthini July 01, 2019

Thermal pollution by power plants - A typical steam turbine power plant uses a fuel (coal, natural gas, oil or nuclear) to heat water into steam in a steam generator. - Steam generated turns a turbine connected to a generator, which produces electricity. - The steam leaving the turbine is then condensed back into water and pumped to the steam generator again to maintain efficient operation. - Condensing steam into water requires cooling by an external source, which is mostly water (known as cooling water). - Cooling water is often drawn from river or sea, to which warm water is returned (in the once-through cooling systems). Prof. R. Shanthini July 01, 2019 http: //www. favstocks. com/why-power-plants-use-so-much-water-and-what-to-do-about-it/296455/

Steam power plant hot gases superheated steam compressed water Steam Generator Steam Turbine Pump C Condenser saturated water Prof. R. Shanthini July 01, 2019 cooling water Gen saturated steam

Steam power plant with Once-Through-Cooling System hot gases superheated steam compressed water Steam Generator Steam Turbine Pump C Condenser saturated water cooling water Cold water Gen saturated steam Warm water River (sea or some other water source) Prof. R. Shanthini July 01, 2019

Thermal shock - Thermal shock is a sudden change in the temperature of the water bodies. - Many aquatic organisms have enzyme systems that are adapted to a very narrow range of temperature. - A sudden temperature change can kill these (stenothermic) organisms. - Power plants design their cooling water discharges to minimize these effects, but periodic heat treatments that flush out the piping can kill fish. - Some power plants have designed a way to increase the heat gradually to drive away fish before the water gets too hot. Prof. R. Shanthini July 01, 2019 http: //www. ehow. com/info_8044447_effects-thermal-pollution-marine-life. html

Thermal shock Even small, chronic changes in the temperature can harm an organism's reproductive system and make them more vulnerable to disease. Prof. R. Shanthini July 01, 2019 http: //www. ehow. com/info_8044447_effects-thermal-pollution-marine-life. html

Dissolved oxygen (DO) depletion - Cold water has more DO than warmer water. - Higher water temperature increases the rate of decomposition of organic matter which depletes the DO in the water. - The heated water increases the metabolic rates of the organisms, increasing their need for sufficient oxygen. Prof. R. Shanthini July 01, 2019 http: //www. ehow. com/info_8044447_effects-thermal-pollution-marine-life. html

Forced migration - Less DO and temperature environments will prompt organisms to move away from the area and populate new areas, radically changing the ecosystems in both areas. - Some power plants have introduced heat-shock proteins to the discharge to protect some organisms from the changes in temperature. Prof. R. Shanthini July 01, 2019 http: //www. ehow. com/info_8044447_effects-thermal-pollution-marine-life. html

Shorter plant life - An increase in water temperature increases the growth rates of aquatic plants, which results in overpopulation of the species. - A rush of warm water can cause an algae bloom that will reduce the oxygen in the water, cause increased plant respiration, and cloud the water. Prof. R. Shanthini July 01, 2019 http: //www. ehow. com/info_8044447_effects-thermal-pollution-marine-life. html

Water for Energy (Water or Energy) - Hydroelectric power generation - Energy resource extraction, refining and processing - Thermoelectric power plant cooling - Biofuel production Prof. R. Shanthini July 01, 2019 http: //www. worldenergy. org/publications/2849. asp