lecture 11 - uchicago geoscigeosci.uchicago.edu/.../2017/slides/slides_lecture11.pdf · 2017. 5....
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GEOS 24705 ENST 24705 ENSC 21100
Lecture 11
Electricity
Electricity generation is now > 1/3 of U.S. power use
Coal usage waning in parts of the world
https://nyti.ms/2p4h24q
EUROPE
For First Time Since 1800s, Britain Goes a DayWithout Burning Coal for ElectricityBy KATRIN BENNHOLD APRIL 21, 2017
LONDON — Friday was the first full day since the height of the Industrial Revolution that Britain did not burn coal togenerate electricity, a development that officials and climate change activists celebrated as a watershed moment.
The accomplishment became official just before 11 p.m., when the 24-hour period ended.
Coal powered Britain into the industrial age and into the 21st century, contributing greatly to the “pea souper”fogs that were thought for decades to be a natural phenomenon of the British climate.
For many living in the mining towns up and down the country, it was not just the backbone of the economy but away of life. But the industry has been in decline for some time. The last deep coal mine closed in December 2015,though open cast mining has continued.
Coal-fired power generation contributes heavily to climate change; burning coal produces twice as much carbondioxide as burning natural gas. Reducing the world’s reliance on coal and increasing the use of renewable energysources like solar and wind power have long been part of proposals to prevent the worst consequences of climatechange.
Now on a path to phase out coal-fired power generation altogether by 2025, Britain, also the home of the first steamengine, is currently closing coal plants and stepping up generation from cleaner natural gas and renewables, like windand solar.
“Symbolically, this is a milestone,” said Sean Kemp, a spokesman for National Grid, Britain’s power gridoperator. “A kind of end of an era.”
The first public coal-fired generator opened at Holborn Viaduct in London in 1882. Since then, the Britisheconomy, one of Europe’s largest, was thought to never have gone without power from coal for a whole working day.
There have been shorter coal-free periods before. Last May, for instance, coal generation dropped to zero for thefirst time, but only for a few hours at a time. On a weekend later that month, National Grid achieved a coal-freestretch of 19 hours, the longest at the time, Mr. Kemp said.
Demand for electricity tends to be lower in the spring, when homes and offices turn off their heating andnormally do not yet have a need for air-conditioning. It tends to be particularly low on a Friday and during the Easterholiday period.
But the trend away from coal as a source of electricity is structural, officials say, with coal-free days likely tobecome more common. Since 2012, two-thirds of Britain’s coal-fired power generating capacity has been shuttered.Some plants have been converted partially to burn biomass, such as wood pellets. Last year, the share of coal in totalpower generation dropped to 9 percent, down from 23 percent in 2015 and 40 percent in 2012.
April 21, 2017
https://www.iea.org/sankey/#?c=United%20Kingdom&s=Balance
Image from: Wikimedia commons
Sta4c electricity discovered in ancient 4mes Word origin: “electricity” from New La>n “electricus”, constructed (1600,
Gilbert, De Magnete) from La>n electrum, “amber”, from Gr. “ilektron”
Kine%c energy à electrical energy: separate charge
Thaleus of Miletus describes 585 BC that amber rubbed with fur could aOract other objects
1660, von Guericke, electrosta>c “generator”
Images from: “The History of Electrosta<c Generators”
Sta4c electricity discovered in ancient 4mes Word origin: “electricity” from New La>n “electricus”, constructed from La>n
electrum, “amber”, Gilbert De Magnete, 1600
Kine%c energy à electrical energy: separate charge
1730s: Hauksbee shows that rubbing amber in a chamber containing mercury vapor causes light emission
1750s, demonstra>on of sta>c electricity discharge: “electric kiss”
Images from: “The History of Electrosta<c Generators”
Sta4c electricity discovered in ancient 4mes Word origin: “electricity” from New La>n “electricus”, constructed from La>n
electrum, “amber”, Gilbert De Magnete, 1600
Kine%c energy à electrical energy: separate charge
1795s: experiments with electrosta>c capacitors (store charge on metal)
Voltaic pile was stack of different metals (Zn, Cu) soaked in brine (inspired by Galvani’s accidental finding).
Images from: Wikipedia, BaBeryfacts.co.uk
Chemical reac4ons can create electric currents Allessandro Volta – demonstrated 1791, “Voltaic pile” 1800
Chemical energy à electrical energy: metal oxidizes
Mary Shelley, 1818
Electricity enters the popular imagina4on Allessandro Volta – demonstrated 1791, “Voltaic pile” 1800
Luigi Galvani frog experiment, 1792