Natural gas cleaner than coal
By Dahli Aspillera
November 06, 2015
MORE electricity from cleaner natural gas; less on dirtier coal. The faster we reduce our dependence on coal for power, the better,” Rep. Arnel Ty. The Liquefied Petroleum Gas Marketers’ Association (LPG-MA) supports a new energy development strategy that will increase the role of natural gas in the country’s fuel mix for power generation.
The country is already 43-percent reliant on coal for power, and this dependency could increase to 70 percent in the years ahead, once additional coal-fired power plants go online, according to the Department of Energy (DOE). Sen. Loren Legarda, chair of the Senate committee on climate change, previously assailed the government’s approval of 21 new coal-fired power plant service contracts in the last five years, saying it ran counter to the Philippines’ pledge to cut CO2 discharges.
Among fossil fuels, coal produces the largest amount of harmful carbon dioxide (CO2) emissions when burned, while natural gas generates the smallest amount, according to Ty, who speaks for the minority in the House energy committee.
Excessive CO2 discharges into the atmosphere have been blamed for rapid global warming and highly destructive climate changes, including rising sea levels, heavier rainfall, stronger storms, and harsher dry spells. “Coal is even dirtier than diesel fuel, which churns out only 161.3 pounds of CO2 per million BTU, and gasoline, which yields 157.2 pounds of CO2 per million BTU,” Ty said.
About 40% of the world’s electricity is generated by burning coal; 21% is generated by burning natural gas. Over the past few years, the percent of natural gas has increased thanks to falling prices and lower emissions. On average, power plants that run on natural gas emit half as much carbon dioxide, less than a third of the nitrogen oxides, one percent of the sulfur oxides, and much lower levels of mercury than plants that burn coal.
Coal-burning power plants are responsible for more than 50% of human-caused releases of mercury in the U.S. Smaller contributions are made by broken devices, burning hazardous waste, and industrial processes that produce chlorine. The top three coal producers are China, the United States, and India. The biggest natural gas producers are the United States, Russia, Canada, and Iran. In the U.S., states that produce the most coal are Wyoming (41%), West Virginia (12%), and Kentucky (10%). The states that produce the most natural gas are Texas (7.1 Tcf), Louisiana (3 Tcf), and Wyoming (2.2 Tcf).
The world has an estimated 948 billion short tons of coal in the ground and 850 trillion cubic meters of recoverable natural gas reserves. To get at coal seams, miners may blast away entire mountains. This permanently alters the landscape and can choke up streams with sediments. About 100,000 Americans have died in accidents in coal mines over the past hundred years. The deadliest year was 1907, when 3,242 deaths occurred.
As of September 2012, about 35% of the “dry” natural gas (relatively pure) produced in the U.S. is shale gas. This is mostly liberated by fracking, in which a well is drilled into rock, then filled with water, sand, and chemicals at high pressure. This causes the rock to crack, and the gas seeps out. Burning coal produces more pollution and more greenhouse gases than burning natural gas. Prices for natural gas have also been low, making the shift more attractive. After natural gas, propane -- the gas in LPG -- is the second-cleanest fuel, generating only 139.0 pounds of CO2 per million BTU.
“Coal is even dirtier than diesel fuel, which churns out only 161.3 pounds of CO2 per million BTU, and gasoline, which yields 157.2 pounds of CO2 per million BTU....” Ty said. The gas from Malampaya, which drives three power plants in Luzon with a combined full generating capacity of 2,700 megawatts, will be depleted by 2024, according to the DOE. The DOE is now drawing up a fuel mix policy that will favor natural gas and renewable energy sources, over coal. The course of action is meant for adoption by the next administration.