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Fuel Sources

Research campuses can reduce carbon emissions and meet climate action goals by using fuel sources with lower carbon emissions.

Carbon Emissions from Various Fuels
  Pounds of CO2
per Million Btu
Grid electricity (high)550
Grid electricity (low)200
Coal230
Fuel oil160
Natural gas120
Wood195
Wind, solar, hydroelectric0

The "high" value for electricity purchased from the power company represents areas where electricity is generated mostly in coal-fired power plants. The "low" value represents areas with greater amounts of electricity generated from hydropower, nuclear, and wind energy on the grid. Wood and other biomass fuels contain "biogenic" carbon, which is part of the natural carbon balance, according to accounting methods developed by the Intergovernmental Panel on Climate Change. Their use does not add carbon into the atmosphere.

The following links go to sections that describe how examining fuel sources may fit into your climate action plans.

The U.S. Department of Energy (DOE) Energy Information Administration (EIA) Web page on carbon emission and thermal energy factors of various fuels illustrates how small changes in the fuel mix can greatly reduce carbon emissions. Switching fuel sources from coal to natural gas cuts carbon dioxide (CO2) emissions by 50% for the same energy load. Many campuses are making this switch as part of their climate action plans.

Another important point is the wide variation in carbon emissions from electricity purchased from the power company because of its fuel mix. As a result, purchasing green power has more carbon offset value for research campuses in areas where utilities generate electricity with high emissions.

Considerations for Campus Fuel Sources

Before undertaking an assessment of fuel sources, a research campus should consider the following.

Central Heating Plants

What fuel mix is right for your campus?
  • Does the campus have a central heating plant?
  • Is a boiler replacement planned?
  • Do you want to reduce your climate impact and carbon footprint?

Fuel source choices for dated central heating plants were based on a variety of factors, but carbon emissions typically were not considered. It is important to evaluate the fuel mix of central heating plants (no matter the age) to determine the best fuel sources and their climate impacts.

Planned Boiler Replacements

Research campuses with plans to update boilers should evaluate new fuel mixes and new technologies. Combined heat and power systems may offer a better solution to meet heating applications and climate action goals.

Reduction of Climate Impact and Carbon Footprint

It is essential to evaluate on-campus combustion emissions, including those from central heating plant combustion, as part of your greenhouse gas inventory. Understanding current fuel sources and system configurations will help you determine opportunities for reduction. If coal is your fuel source, you should consider a different fuel to support your greenhouse gas mitigation plan.

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Leading Example: National Renewable Energy Laboratory Renewable Fuel Heating Plant

Aerial photo of a rectangular one-story building with a large entry door—big enough for trucks to make deliveries of wood chips—on the left-hand side. A short stack protrudes from the roof at the other end of the building. In the background is a larger building that is surrounded by delivery trucks and miscellaneous equipment.

The NREL biomass heating facility supplies 52% of the laboratory's yearly heating load.
Credit: Patrick Corkery

The National Renewable Energy Laboratory (NREL) in Golden, Colorado, evaluated fuel sources for its central heating plant with an eye toward reducing greenhouse gas emissions. In 2008, the laboratory contracted to build its Renewable Fuel Heating Plant, which uses wood and forest thinnings from a nearby national forest for fuel.

A private company, Ameresco, financed and built the plant and operates it for NREL. In turn, NREL pays the company the savings from its utility bills for natural gas until the plant is paid for.

The facility saves 41 billion Btu of natural gas annually, preventing 2,200 metric tons of carbon emissions each year. The $3.3 million project saves more than $400,000 each year, generating a simple payback of approximately 25 years.

You can find details about the facility from the NREL fact sheet titled, "Renewable Fuels Heating Plant".

Additional examples of research campuses fuel source projects include:

  • Cornell University: Has replaced coal combustion with natural gas through a combined heat and power system.

  • University of Wisconsin: Plans to convert its coal-fired plant to burn a combination of natural gas and biomass to significantly reduce greenhouse gas emissions and meet climate action goals.

  • Ball State University: Is undergoing ambitious projects to its convert coal-fired plant to electricity-powered ground-source heat pumps that greatly reduce carbon emissions.

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These resources explain the fundamentals of fuel sources:

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