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Today's Paper | November 14, 2024

Published 07 Aug, 2013 07:54am

Pollution from coal-fired power plants

APROPOS news reports (July 25 and 28), the Punjab government will set up large power plants in Karachi to produce 3,000 megawatts of electricity through coal. It will also set up four coal power plants at Gadani to generate 2,400 MW of electricity.

While it is not known why Punjab is setting up coal-fired power plants in Balochistan and Sindh, and not in Punjab, one thing is for sure: the coal-fired power plants are massive environmental polluters.

Coal-fired power plants are major polluters, impacting all spheres of environment -– water, air and land. The pollution caused by coal plants is equivalent to pollution caused by nine other top polluting industries combined. While other industries’ waste stream may be 50 or so per cent toxic, the waste stream of coal plants is 100 per cent toxic.

Coal plants cause significant and irreversible water pollution. The major constituents of the waste streams are arsenic, lead, mercury, cadmium, boron, selenium, bromides, nitrogen and phosphorus.

Arsenic is a potent poison. It can build up, or bioaccumulate, in ecosystems. When ingested, it can cause cancer, skin and internal organ tumors, heart problems, nervous system disorders, intense stomach pain, stillbirths and miscarriages.

Lead is a toxic poison that can cause severe brain damage, especially in children. Lead enters the food chain and bioaccumulate, creating a huge problem for the wildlife and the people.

Mercury is a highly toxic element and its unique characteristic is that, even in small quantities, it can cause major disasters. To put this into perspective, a fraction of a teaspoon of mercury can contaminate a 25-acre lake.

Mercury causes nervous system and kidney damage, and impairs brain development in children.

Mercury also accumulates in fish. The episode of Minimata Disease in Japan occurred when people near Minimata Bay started eating mercury-contaminated fish.

Cadmium, boron, selenium, and bromides are also toxic in nature. Nitrogen and phosphorus cause massive algal blooms in water bodies.

Coal plants are the top sources for emissions of carbon dioxide (CO2), a major global warming gas. A typical coal plant generates about 3.5 million tons of CO2 per year. In addition to haze, smog and acid rain caused by emissions from coal plants, the emissions contain many toxic constituents.

These include: particulate matter (causes asthma, bronchitis and premature death); Oxides of nitrogen (cause respiratory diseases, burn lung tissue and form ground-level ozone); Sulfur dioxide (destroys crops, forests and soils; Acidifies water bodies, and form acidic particulates that penetrate deep into lungs of human beings);

Carbon monoxide (causes headaches and exacerbates health of people with heart disease);

Mercury, lead, cadmium, uranium, hydrocarbons and volatile organic compounds.

Solid waste (ash and sludge from the smokestack) contains arsenic, cadmium, chromium and mercury and can contaminate water sources (including groundwater resources), destroys vital human organs and nervous system, and destroys soils and landscape across wide areas.

Coal plants draw, typically, 100bn gallons of water a year from river or lake, for their once-through cooling systems. When the water is released back into the water body, it is hotter by 4 degrees Celsius. This thermal pollution is detrimental to aquatic life, as it increases heart rates in fish and, decrease fertility.

Coal power plants also add copper sulfate, chlorine or other toxic chemicals to their cooling water, to retard algal growth. These chemicals are discharged back to the water bodies, with major consequences.

The list of adverse impacts of coal power plants can go on and on. Coal is the most carbon-intensive of all fossil fuels. It is nearly all carbon, so it releases almost entirely carbon dioxide when burned.

Two alternatives stand strongly as alternative to coal power plants. Increasing energy efficiency is a clean way to meet the people’s energy needs. Just one aspect of energy efficiency – energy-efficient buildings, can right away reduce energy demand by 60 per cent.

The second alternative is the use of renewable energy. Jhimpir in Thatta district has a great potential for installation of wind turbines.

F. H. MUGHALKarachi

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