As part of its Beyond Coal campaign, the Sierra Club tracks the amount of carbon dioxide that it calculates has been avoided as as result of cancellations of proposed coal plants. It is an impressive number--630 million tons annually. http://www.sierraclub.org/environmentallaw/coal/plantlist.aspx.
But that is not all the carbon dioxide that has been avoided in the last decade.
Coal's market share has declined from 52% in 2000 to 37% projected for 2012. The 15 percentage point decline in coal has yielded a corresponding rise in natural gas and renewable energy of about 10 and 5 percentage points respectively. Each percentage point decline in coal's market share reduces carbon emissions by about 45 million tons.
Given that renewable energy typically is zero carbon and natural gas generation emits 50% less carbon than coal, replacing 10 percentage points of coal generation with natural gas produces a net carbon benefit of about 225 million tons per year and replacing 5 percentage points of coal with renewable energy avoids another 225 million tons.
The total carbon benefit from the change in the market share of coal, gas and renewable energy between 2000 and 2012 is about annually 450 million tons, more than 1% of world emissions.
One billion tons of carbon dioxide avoided is the result when one adds together the 630 million tons of carbon avoided from coal plant cancellations tracked by the Sierra Club with the 450 million tons avoided by the decrease in coal's market share and corresponding increases in natural gas and renewable energy. That's a huge amount equal to about 18% of US energy related carbon emissions and 3% of world carbon pollution.
All that is very good news but inconvenient to those demonizing natural gas.
Why has so much carbon been avoided and so many new coal plants cancelled since 2005? Why has the Sierra Club been able to claim such success for its campaign? It certainly was not a national cap and trade law, as that went down to a crashing Congressional defeat.
The closest the Sierra Club comes to saying "natural gas stopped the coal rush" is to mention ambiguously the role of changed "market conditions." Yet, while slowing the rate of electricity demand increases and increasing renewable supply contributed to new economic realities, the key changed market condition was that the price of natural gas--coal's principal competitor--dropped like a stone. Why?
The shale gas boom that took off in 2007 turned natural gas prices from high to low.
Without the rise of shale gas, the Sierra Club's Beyond Coal campaign would have largely failed, though a smaller percentage of the proposed plants would have been cancelled anyway. Mayor Bloomberg who generously funds the Beyond Coal campaign may understand this well.
Prior to the shale gas boom, America was preparing in 2005 to import large amounts of Liquefied Natural Gas (LNG) and natural gas prices were steadily rising, peaking in July 2008 at $13 for a thousand cubic feet. At those gas prices, generators concluded that coal was their only option to provide generation that could run around the clock to meet demand. The rush to build 150 new coal plants was on.
But the crash of natural gas prices from $13 to $4 and then to $2 not only stopped the rush to build new coal plants but also caused existing dual fuel plants to switch immediately from coal to gas. Southern Company, once America's top consumer of coal, went almost overnight from getting 70% of its electricity from burning coal to 32%, as one example. www.johnhanger.blogspot.com/2012/04/southern-company-leading-nation-in.html
Still other owners of old coal plants announced that they would retire operating but old coal plants, because they could no longer compete with newly competitive natural gas generation that had sat nearly idle for 10 years, when gas was so expensive that running it was uneconomic. Cheap gas crashed the wholesale price of electricity, making inefficient, old coal plants the equivalent of a player, without a chair, when the music stops in a game of musical chairs.
And make no mistake the price of gas would not have crashed without the shale gas boom that now provides 30% or more of America's natural gas. And without shale gas, the coal rush would not have stopped; Southern and other power companies would not have switched their dual fuel plants to gas; and many less than 107 old coal plants would have retired or been scheduled for retirement.
Yet, despite the massive carbon, mercury, soot, and lead benefits provided by the rise of gas, the bashing of gas is now politically correct, even a political imperative, in some but not quite all environmental circles. In green precincts, denying the environmental benefits of natural gas is becoming as required as denying climate change is in conservative politics.
Certainly, gas production has negative impacts too, though less than coal, oil, corn ethanol, and many other industries. Gas production is industrial activity and cannot be done with zero impact. And it is important to work to lessen the negative impacts of gas production.
But natural gas can and should be made cleaner by further reducing methane leakage and insisting on strong regulation. The EPA final gas air emissions rule is an important step in that direction.
Even so, by displacing coal and oil, the rise of gas is delivering massive pollution reductions. And today's hyperbolic, factually unbalanced gas bashing has become itself a threat to the environment and public health.