Carbon dioxide emissions: Focus of attention
August 21, 2012
by Anne Giesecke
For a few weeks this spring the Environmental Protection Agency (E.P.A.) considered an air permit threshold of 250 tons per year (tpy) of carbon dioxide equivalent (CO2e) emissions. Even a relatively small 3 line bakery will emit about 6,500 tonnes of CO2e each year. A tonne is 2,204.6 U.S. lbs.
For the bakery above, sources of CO2e are the carbon dioxide from the burning of fossil fuels such as diesel, petroleum and natural gas both on-site, about 2,000 tonnes, and from the purchase of electric power, about 3,500 tonnes. In addition, wastewater treatment gases such as methane, about 200 tonnes, and refrigerants such as the release of hydrofluorocarbons, about 800 tonnes, could be in the count. Methane and refrigerants are converted to a carbon dioxide equivalent.
For government reporting, fuel for cars and trucks probably will be counted by refineries not individual plants. Biogenic sources such as carbon dioxide emissions from fermentation and from trees are not counted now.
One program to calculate a carbon footprint for energy use is found at Carbon Footprint, www.carbonfootprint.com/businesscalculator.aspx. (See Milling & Baking News of May 5, 2009, Page 26).
Fortunately, on June 29, 2012, the E.P.A. issued a final rule titled, Prevention of Significant Deterioration and Title V Operating Permit Greenhouse Gas (G.H.G.) Tailoring Rule Step 3 and G.H.G. Plantwide Applicability Limits that does not revise the greenhouse gas (G.H.G.) permitting thresholds established in 2011. These emission thresholds determine when Clean Air Act permits under the New Source Review Prevention of Significant Deterioration (P.S.D.) and Title V Operating Permit programs are required for new and existing industrial facilities. Additional rule elements were published Aug. 13, 2012.
According to the E.P.A. 2011 thresholds, new facilities with G.H.G. emissions of at least 100,000 t.p.y. CO2e and existing facilities with at least 100,000 t.p.y. CO2e making changes that would increase G.H.G. emissions by at least 75,000 t.p.y. CO2e are required to obtain P.S.D. permits. Facilities that must obtain a P.S.D. permit anyway, to cover other regulated pollutants, must also address G.H.G. emissions increases of 75,000 t.p.y. CO2e or more. New and existing sources with G.H.G. emissions above 100,000 t.p.y. CO2e also must obtain operating permits. The E.P.A. uses a U.S. ton of 2,000 lbs. (www.epa.gov/nsr/actions.html#2012.)
After evaluating comments on the proposed 100 t.p.y. and 250 t.p.y. thresholds, the E.P.A. determined that state permitting authorities have not had sufficient time to develop necessary permitting infrastructure. At this time, the agency concluded that is not appropriate to apply P.S.D. and Title V permitting requirements to additional, smaller sources of G.H.G. emissions.
Industries that are captured by the rule include electronics manufacturing, petroleum and natural gas systems, electric transmission and distribution equipment, imports and exports of equipment pre-charged with fluorinated G.H.G.s or containing fluorinated G.H.G.s in closed-cell foams, geologic sequestration of carbon dioxide, manufacture of electric transmission and distribution equipment, injection of carbon dioxide.
The primary G.H.G. is carbon dioxide. According to the annual report, titled “Trends in global CO2 emissions,” released by the European Commission’s Joint Research Centre and The Netherlands Environmental Assessment Agency, global emissions of carbon dioxide (CO2), the main cause of global warming, increased by 3% last year, reaching an all-time high of 34 billion tonnes in 2011. In China, the world’s most populous country, average emissions of CO2 increased by 9% to 7.2 tonnes per capita. In the European Union, CO2 emissions dropped by 3% to 7.5 tonnes per capita. The United States remains one of the largest emitters of CO2, with 17.3 tonnes per capita, despite a decline due to the recession in 2008-2009, high oil prices and an increased share of natural gas.
The 3% increase in global CO2 emissions in 2011 is above the past decade’s average annual increase of 2.7%. The top emitters in 2011 were: China (29%), the United States (16%), the European Union (11%), India (6%), the Russian Federation (5%) and Japan (4%).
The trend for concern about climate change will continue. Based on analyzing a number of indirect measures of climate such as ice cores, tree rings, glacier lengths, pollen remains, and ocean sediments, and by studying changes in Earth’s orbit around the sun, Natural Research Council scientists have constructed a time-line dating back hundreds of thousands of years.
Scientists on the Intergovernmental Panel on Climate Change have concluded that the global average temperature increased by more than 1.4°F over the last 100 years. According to the National Oceanic and Atmospheric Administration, the decade from 2000 to 2010 was the warmest on record, and 2010 was tied with 2005 as the warmest year on record. The Panel also concluded that rising global temperatures have been accompanied by other changes in weather and climate. Many places have experienced changes in rainfall resulting in more intense rain, as well as more frequent and severe heat waves. The planet’s oceans and glaciers also have experienced changes: oceans are warming and becoming more acidic, ice caps are melting, and sea levels are rising.
All of these changes are evidence that our world is getting warmer and that the price of energy will increase as the number of related government regulations increase.