Electricity generation in the United States is broken into 26 different regions. For example, most of New York State is in the upstate region (NYUP), but New York City (NYCW) and Long Island (NYLI) have their own regions. Within each of these regions, the total electricity generation and total GHG emissions are averaged to provide regional emission factors for the overall mix of electricity. This is often also done at the state level.
Table 1 provides values for regional emission factors that are averaged over all types of electricity generation. Emission factors for CO2 vary by more than a factor of three among the regions. New York State, for example, is well below the national average. These emission factors were compiled by the U.S. EPA’s eGrid program. They only include combustion related (stack) emissions, not total lifecycle emissions.
Table 1: 2007 GHG Annual Electricity Output Emission Rates by Region
(see map above)
Carbon dioxide (kg CO2/MWh)
Nitrous oxide (kg N2O/MWh)
This project module includes three in class activities and a homework assignment. The different activities are geared towards different age levels. Collectively, the set of activities can be used to explain electricity generation systems, their efficiency and differences in greenhouse gas generation.
Activity appropriate for:
Energy efficiency activity
Lifecycle electricity generation poster
Review of U.S. EPA Power Profiler results
Homework – application of electricity mix and emission factors to determine state average
* perhaps best without the prepared cut-outs the younger students get
Anticipatory Set A brainstorm about how we use energy and then specifically electric energy will get students engaged in thinking about energy overall and its split between electrical and other forms. A powerpoint lecture is available to introduce some of the key concepts:
Procedure This unit has three primary activities and an associated homework assignment. The selection of which activities are completed depends mostly on the age and learning level of the students. The first two activities are best completed by groups (3-4) students. The Review of the Power Profiler tool can be done individually or in pairs at a computer. An introductory powerpoint lecture is available to introduce aspects of the materials. Suggested timeline:
Day 1: Introduction and energy efficiency activity
Days 2-3: Create and briefly present the lifecycle posters
Day 4: Use Power Profiler tool and summarize on worksheet (assign HW if appropriate for grade level)
Closure The students should have mastered all of the learning objectives through the series of activities included here. A general discussion could include:
This unit can be used to connect science, technology and environmental science topics. There are opportunities for extensions in any of these areas. For example – more on the combustion chemical reactions for a physical science class, electricity generation technologies and alternatives in a technology class, or consequences (climate change, acid rain, etc.) for an environmental science class.
The following New York State Science Standards are supported by this module:
STANDARD 1—Analysis, Inquiry, and Design
Students will use mathematical analysis, scientific inquiry, and engineering design, as appropriate, to pose questions, seek answers, and develop solutions.
STANDARD 3- Mathematics
Students will understand mathematics and become mathematically confident by communicating and reasoning mathematically, by applying mathematics in real world settings, and by solving problems through the integrated study of number systems, geometry, algebra, data analysis, probability and trigonometry.
STANDARD 4- Science
Students will understand and apply scientific concepts, principles, and theories pertaining to the physical setting and living environment and recognize the historical development of ideas in science.
STANDARD 6—Interconnectedness: Common Themes
Students will understand the relationships and common themes that connect mathematics, science, and technology and apply the themes to these and other areas of learning
The following National Common Core Mathematics Standards are supported by this module: (http://www.corestandards.org/the-standards/mathematics )
Students will be able to:
G-MG.3. Apply geometric methods to solve design problems Use units as a way to understand problems and to guide the solution of multi-step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs and data displays.
N-Q.2. Define appropriate quantities for the purpose of descriptive modeling.
G-MG.3. Apply geometric methods to solve design problems
S-ID.1. Represent data with plots on the real number line (dot plots, histograms, and box plots).
The lifecycle posters and Power Profiler worksheet can be collected and graded as part of the assessment. The college-level homework assignment also provides a means of assessing if the students understand the concepts and met the learning objectives.
Energy Efficiency Activity
Electricity, efficiency and emissions powerpoint lecture
Cut-outs for electricity generation lifecycle poster
U.S. EPA Power Profiler
Student worksheet for Power Profiler activity
Homework assignment - State emission factors for electricity (geared for college, perhaps also HS students)
 U.S. DOE EIA, What are greenhouse gases and how much are emitted by the United States? http://www.eia.gov/energy_in_brief/greenhouse_gas.cfm(accessed 6/2/2011)
 USEPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2009, April 2011. USEPA #430-R-11-005 (http://www.epa.gov/climatechange/emissions/usinventoryreport.html )
 U.S. DOE EIA, Annual Energy Outlook, 2011: Emissions from Energy Use. April 2011, Report Number: DOE/EIA-0383(2011) Table 30 http://www.eia.gov/forecasts/aeo/topic_emissions.cfm
 U.S. DOE EIA, Emissions of Greenhouse Gases in the U. S. March 31, Report Number: DOE/EIA-0573(2009) http://www.eia.gov/environment/emissions/ghg_report/ghg_overview.cfm(accessed 6/2/2011)
 Spadaro, J.V., L. Langlois, and B. Hamilton, 2000. Greenhouse gas emissions of electricity generation chains – Assessing the difference. IAEA Bulletin, 422: 19-24. http://www.iaea.org/Publications/Magazines/Bulletin/Bull422/article4.pdf
 U.S. EPA eGRID2010 Version 1.1, http://www.epa.gov/cleanenergy/documents/egridzips/eGRID2010V1_1_year07_GHGOutputrates.pdf(accessed 6/2/2011)