The production of coal energy is coming to an end with the last Ontario plant scheduled for closure in 2014. Now Canadians are looking to other sources of fuel for electricity production to make up the base and demand loads necessary to guarantee an uninterrupted supply to homes and industry. With nuclear energy proving too expensive and potentially dangerous, many countries are turning to natural gas as a viable alternative. Now some environmentalists are questioning claims that natural gas is a clean, green source of energy.
“The large GHG footprint of shale gas undercuts the logic of its use as a bridging fuel over the coming decades, if the goal is to reduce global warming,” says Professor Robert Howarth, Cornell University. The objection to natural gas is twofold: there are substantial carbon emissions during energy production and the process of fracking (which is used when mining natural gas) contributes just as much to global warming as coal-fired plants do.
Natural gas originally won its green-energy status because its carbon emissions are about half those of coal-fired energy plants. Natural gas is a non-renewable resource that is extracted, cleaned and then burned in turbines and boilers to create steam, power turbines and produce electricity. Plants powered by gas do output reduced nitrogen oxide and carbon monoxide emissions when compared to coal-burning plants. However, methane released when gas is not completely burned, as well as during the production of natural gas negate the positive aspect gas plants enjoy.
Fracking is the process of extracting natural gas that is trapped deep beneath shale beds. Long wells are drilled to the gas reserves (usually about 1km or deeper). A mixture of chemicals, water and sand is then pumped into the ground to force the gas up through fissures in the shale where it is collected. We are not entirely sure what impact fracking has on the environment as the cocktail of chemicals used in the process has been deemed a ‘trade secret’. We are, however, able to measure the emissions from plants that produce natural gas. A February 2012 study discovered that the production, transportation and burning of natural gas caused the release of considerable amounts of methane into the atmosphere.
Fracking has also been linked to water pollution, earthquakes and the destruction of pristine environments. New studies show that the chemical cocktail used in fracking will leach into groundwater aquifers sooner than expected. France and Bulgaria have banned fracking in reaction to environmental concerns, but the practice is still enjoying unprecedented growth in the US, Canada, the UK, Australia, China and other countries. In the US, shale gas accounts for about a quarter of the nation’s gas production. 70% of gas wells in Canada utilize fracking in the extraction processes.
The EPA sets the average leakage of gas production plants at 3.3% and that number increases to 9.7% where fracking is employed to extract gas. Natural gas consists of 85% methane and is a whopping 105 times worse for global warming than other greenhouse gas emissions. Methane on its own is 25 times better at trapping heat in the atmosphere than carbon dioxide. When methane reacts with aerosols in the atmosphere, this global warming effect is compounded.
The idea that natural gas may provide a panacea to our energy needs is being challenged. This has not had a discernible impact on the growth of gas plants according to Sheamus MacLean of Economic Performance Architects. Cheap gas prices have led to the adoption of this form of energy production over renewable energy sources like wind or solar. Reliance on natural gas energy may prove to be a leap from the frying pan into the fire due to the global warming and environmental impacts of gas extraction and energy production.