Norfolk Southern’s absolute emissions of greenhouse gases increased in 2013 as business volumes grew. Strategic operations initiatives helped curb the rate of increase, including the use of technologies that improve locomotive fuel economy and increase the energy efficiency of office buildings and rail facilities.

Goal: To reduce carbon emissions by 10 percent per revenue ton-mile between 2009 and 2014.

Status: By the end of 2013, the company had achieved nearly 79 percent of our goal, reducing emissions by 7.8 percent per revenue ton-mile.

Emissions Goal Status

In 2010, Norfolk Southern set a five-year goal to reduce greenhouse gas emissions by 10 percent per revenue ton-mile by the end of 2014.

For this year’s sustainability report, Norfolk Southern changed our presentation of CO2 emissions, a primary greenhouse gas. To calculate the railroad’s CO2 emissions in 2013, we excluded the direct CO2 emissions generated from the consumption of approximately 11 million gallons of biodiesel locomotive fuel. In past sustainability reports, we had included the plant-based fuel in our CO2 calculations, giving it the same emissions weight as petroleum diesel, the company’s main locomotive fuel source.

The change is in accordance with Greenhouse Gas Protocol reporting standards. According to the Alternative Fuels Data Center, a resource for the U.S. Department of Energy, use of biodiesel actually reduces CO2 emissions: CO2 released during combustion is offset by the carbon dioxide captured while growing soybeans and other feedstock used to produce the fuel. The nearly 11 percent biodiesel mix the company purchases in Illinois to fuel locomotives at Chicago and Decatur rail facilities reduces CO2 emissions by roughly the same percentage as the blend.

With biodiesel excluded from the CO2 calculations, the company reports achieving nearly 79 percent of our goal by the end of 2013, the fourth year of our five-year goal.

The company included biodiesel use to calculate emissions of nitrous oxide (N20) and methane (CH₄) – the other primary components of fossil fuel generated greenhouse gas – because biodiesel combustion generates roughly the same amount of those gases as does petroleum diesel combustion.

How We Measure Progress Toward Our Goal

Norfolk Southern calculates progress on our greenhouse gas reduction goal using revenue ton-miles, an accepted industry metric for measuring business activity. This provides a normalized basis to gauge progress regardless of business growth or decline.

The goal’s baseline year came from 2009 performance data. That year, the railroad transported 158.5 billion revenue ton-miles of freight and produced emissions of 29.96 grams of CO2 equivalents per revenue ton-mile. We rounded the baseline to 30 grams.

To meet the reduction goal of 10 percent per revenue ton-mile, emissions must be reduced to 27 grams per revenue ton-mile. For 2013, the company moved 193.5 billion revenue ton-miles of freight and generated 27.64 grams of CO2 equivalents per revenue ton-mile.

We set the bar high by aiming for a 10 percent reduction, concluding that it would be better to be ambitious and fall short rather than set an easily achieved standard. Over time, the company aspires to achieve reductions in absolute emissions even as business volumes grow.

Improved Carbon Disclosure Score

Norfolk Southern continues to make progress managing carbon, achieving our best-ever score on carbon disclosure in the CDP S&P 500 Climate Change Report 2013 and the CDP Global 500 Climate Change Report 2013.

The railroad scored 90 on a scale of 100 for carbon disclosure. That is a 2 percent improvement over the 2012 score of 88 and is the company’s highest score in six years of participating in the voluntary CDP survey. Of 44 U.S. industrial-sector corporations in the CDP’s S&P 500 report, Norfolk Southern was among 14 that scored 90 or higher.

CDP gave Norfolk Southern a performance grade of B, on a scale of A to E, on efforts to mitigate climate change and reduce greenhouse gas emissions. That matches performance in 2012 and 2011.

CDP, formerly known as the Carbon Disclosure Project, is an independent not-for-profit organization that supports greenhouse gas emissions reduction and sustainable use of water and forest resources.

“We are taking a comprehensive, strategic approach to reduce emissions. We are committed to maintaining a high-quality system that leverages freight rail’s inherent efficiencies in support of the economy, less highway congestion, and lower overall fuel consumption and greenhouse gas emissions.”

Blair Wimbush, vice president real estate and corporate sustainability officer

2013 Carbon Footprint

During 2013, Norfolk Southern Corporation generated 5.35 million metric tons of greenhouse gas emissions. The total includes 5.09 million metric tons of direct Scope 1 emissions from business operations; 260,792 metric tons of indirect Scope 2 emissions from the generation of purchased energy; and 6,346 metric tons of indirect Scope 3 emissions from employee travel and energy use at leased facilities.

Scope 1 emissions were generated primarily by the company’s diesel-burning locomotive fleet, accounting for 90 percent of total emissions. Scope 2 emissions, 5 percent of the total, were derived from the company’s use of purchased electricity to heat, cool, and light office buildings and railroad facilities. The calculated Scope 3 emissions were associated with employee business travel, by air and in personal vehicles, and with the company’s electricity use at leased facilities.

The railroad’s absolute emissions of greenhouse gases increased 3.3 percent over 2012 emissions. We attribute the increase primarily to three factors. Chief among them was a 4.3 percent increase in revenue ton-miles, reflecting an increase in business volumes that drove up year-over-year use of diesel fuel by 5 percent. Another factor was a continuing change in business mix that resulted in an increase of high-velocity intermodal freight and a decline in coal carloads. Locomotives pulling time-sensitive intermodal freight typically operate at higher horsepower, thus consuming more fuel, to meet customer service demands. Heavy coal trains, which operate at slower speeds and over downhill routes from mountain mining sites, are among the most fuel-efficient. The third factor was weather-related rail traffic congestion caused by snow, ice, and storms.

Avoiding Carbon Emissions

Strategic efforts to improve fuel and operating efficiencies helped offset the rise in absolute emissions. For example, the emissions increase was 1 percentage point below the growth in revenue ton-miles, a difference attributed to the company’s emissions-reduction strategies. In one key initiative, the railroad estimates that locomotives equipped with LEADER, a train-handling technology, saved more than 10 million gallons of diesel during the year. That translates into an equivalent CO2 avoidance of around 110,500 metric tons.

Overall, the company projects that fuel-efficiency initiatives resulted in avoided emissions of about 2.6 percent.

Norfolk Southern 2013 emissions (in metric tons CO2e)

  Scope 1 Scope 2 Scope 3
CO2 5,040,534 259,429 6,327
CH4 9,832 110 2
N2O 37,949 1,253 17
HFCs 0 0 0
PFCs 0 0 0
SF6 0 0 0
SUBTOTAL 5,088,315 260,792 6,346
Total 5,355,453 MT CO2e
total CO2 equivalent emissions

Auditing firm KPMG LLP reviewed the raw data and methodologies that Norfolk Southern followed to calculate the company’s 2013 greenhouse gas emissions, as presented in the above chart of the railroad’s CO2 equivalent emissions. To read the assurance letter provided by KPMG, please click here.


2009 2010 2011 2012 2013
Total Scope 1 and Scope 2 emissions of carbon dioxide equivalents
4.7 5.2 5.4 5.18 5.34
Emissions per revenue ton-mile (GRAMS) 29.96 28.78 28.78 27.93 27.63
Total revenue ton-miles of freight moved (BILLIONS) 158.5 181.9 191.7 185.6 193.55
Total railway operating revenues
7.9 9.5 11.2 11.0 11.24

Percentage of carbon dioxide emissions by source