This document proposes recommendations for General Motors' Fort Wayne Assembly plant to increase its use of renewable energy. It recommends: 1. Installing 14 wind turbines that are 2.5 MW and 100m tall to generate 50% of the plant's energy needs. Based on average wind speeds in the region, this setup could supply half of FWA's electricity. 2. Doubling the landfill gas capacity to achieve the target of 50% on-site power generation. Processing landfill gas into electricity would save $1.7 million annually and have a two-year return on investment. 3. Combining these recommendations could save GM money while further reducing the plant's carbon emissions and solidifying its status

1. Table 1 Greenhouse gas emissions by source
Greenhouse gas (GHG) emissions are important for
GM to track to maintain its status as a global green
leader. Landfill gas processed in an engine may seem
like a poor choice, since it emits much more pollution for
every MWh of energy produced.
However, landfills will inevitably emit gases for the next
thousand years, since they are fixed operations.
Currently, operators have three choices when dealing
with landfill waste gas: emitting raw gas, flaring it, or
processing it for energy.
Since emissions are inevitable, the best option is to
obtain a useful product like energy. Therefore, landfill gas
is still a sustainable energy source despite its
appearance.
Indiana’s grid mix relies heavily on coal, which comprises
65% of its energy portfolio. Renewable energy sources
are minimally used in the state, so GM will see a
reduction in carbon emissions if it switches to either wind
or solar, which both have low emission rates.
SUSTAINABILITY
RENEWABLE ENERGY FOR GENERAL
MOTORS’ FORT WAYNE ASSEMBLY
The team would like to thank Rob Threlkeld, GM’s
Global Manager of Renewable Energy, for his
mentorship and support throughout the project. Thank
you to Dave Shenefield for hosting us at FWA, and
thank you to Purdue’s project instructional team.
General Motors (GM), a Fortune 100 company, is one of
the nation’s leaders in renewable energy, with
renewables powering almost one-tenth of its North
American operations. GM benefits from this energy
conversion through reduced operating expenses,
increased security of energy infrastructure and
availability, and enhanced public relations. In fact, one of
its manufacturing facilities in Indiana, Fort Wayne
Assembly (FWA), has saved millions of dollars since
implementing technology that converts landfill gas to
energy. Recently, GM announced a major expansion of
FWA, a truck and SUV manufacturing plant in Indiana.
This expansion will further increase the site’s energy
needs. To achieve future cost savings and continue its
leadership in sustainability, GM is looking to increase its
renewable energy portfolio—making FWA the first GM
plant to run on 100% renewable energy.
[1] “Commercial Solar Carport Mount Systems.” Solar Electric Supply, Inc. N.d.
Web. 29 Nov. 2015.
[2] “Fast Facts.” National Wind Watch. N.d. Web. 29 Nov. 2015..
[3] "The Clean Energy Standard Act Of 2012." United States Senate Committee
on Energy & Natural Resources, 2012. Web. 28 Aug. 2015
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[4] Chen, Cliff, and Nathaneal Green. "Is Landfill Gas Green Energy." (March
2003): pg.7.
Nrdc.org. Natural Resources Defense Council. Web.
[5] Guezuraga, Begona, Rudolf Zauner, and Werner Polz. "Life Cycle
Assessment of Two Different 2 MW Class Wind Turbines." ScienceDirect.
Renewable Energy, Jan. 2012. Web. 25 Feb. 2016.
[6] "Indiana - 100 Meter Wind Speed." : In.gov. U.S. Department of Energy
National Renewable Energy Laboratory, 23 Jan. 2006. Web. 20 Mar. 2016.
[7] Chung, Donald, Carolyn Davidson, Ran Fu, Kristen Ardani, and Robert
Margolis. "U.S. Photovoltaic Prices and Cost Breakdowns. Q1 2015
Benchmarks for Residential, Commercial, and Utility-Scale Systems." (2015):
Web. 10 Mar. 2016.
Kim Reppa, Alexander Nathan, Yvonne Shi, Boaz Shachaf
Environmental and Ecological Engineering, Purdue University, West Lafayette, IN
INTRODUCTION FORT WAYNE ASSEMBLY METHODSDESIGN TARGETS METHODS
Figure 2 The total costs of different energy sourcing
options, normalized on a megawatt hour basis. The price
of Indiana’s grid mix will remain steady for the next 24
years, whereas wind energy will remain less expensive.
LEVELIZED COST OF ELECTRICITY
SOURCE 100% ELECTRICITY
FROM RENEWABLES
GENERATE 50% OF ENERGY
DEMAND ON-SITE
ACHIEVE A 3-YEAR
RETURN-ON-INVESTMENT
1
2
3
Figure 3 Average wind speeds at 100m above the
region where the PJM Interconnection grid is located
FWA receives its energy from the PJM Interconnection,
which is the area highlighted in shades of blue. Wind
speed in this region varies by elevation. At 100m, speeds
average between 7 and 8 m/s, and turbine efficiency is
between 30 and 39%.
WIND ENERGY POTENTIAL METHODSDESIGN RECOMMENDATIONS
1
2
3
14 TURBINES
2.5 MW, 100m TALL
110% INCREASE IN LANDFILL GAS
$1.7M ANNUAL SAVINGS +
2-YEAR ROI
• No state-wide wind regulations
• Fort Wayne’s electrical grid is in a deregulated market
• However, Indiana is a regulated state
• All Indiana energy providers must be
registered as regulated utilities
• In-house electricity generation does not
need to be registered
ADDITIONAL CONSIDERATIONS
LITERATURE CITED
ACKNOWLEDGMENTS
Assuming an average efficiency of 35%, at an elevation
of 100m, using standard 2.5 MW turbines, FWA would
need 14 wind turbines to supply 50% of its energy.
To achieve a target of 50% on-site power generation, it
is recommended the site double its landfill gas capacity.
Source
GHG Emissions
(lb CO2e/MWh)
Landfill Gas 68,855
Indiana Grid Mix 1,942
Wind Turbines 0.3
Solar Panels 0
Figure 1 Purdue senior design team with Rob Threlkeld,
GM’s Global Manager of Renewable Energy. The yellow
engines in the image are used to process landfill gas into
electricity.
GM can save $1.7M per year by implementing design
recommendation (1) through a power purchase
agreement. Implementing design recommendation (2)
has an ROI of 2 years.
Figure 4 Landfill gas procurement through a fixed 2%
price escalation contract provides a $9.7M savings
differential over 20 years when compared to a take-or-
pay contract