Generate LFG Electricity for Microgrid

As costs for energy storage have come down, electricity generated from landfill gas (LFG) can be stored as part of a microgrid system. A microgrid:

Is an independent and self-sufficient local distributed energy system that can provide electricity directly to a defined set of end users.
Often includes energy storage components to provide backup power.
Can be connected to a larger grid system for additional reliability.
Can include electric vehicle charging stations if there is demand for electrical fleets within the region served by the grid.

Example

Miramar Microgrid, California ^{3, 4, 5, 6, 7, 8}

Electricity generation from LFG at the West Miramar Landfill in San Diego, California began in 1997 with eight reciprocating engines and waste heat recovery. In 2012, third-party project owner Fortistar added two new engines with a combined rated capacity of 3.2 MW—this green power is now delivered to the Marine Corps Air Station (MCAS) Miramar via a 6.5-mile power line under a 15-year power purchase agreement.

MCAS Miramar has a 36-square-mile footprint with a population of more than 15,000 personnel and family members. The station’s microgrid began as a vision in 2011 through its pursuit of energy security and sustainability and was officially completed in 2020. Designed and built by Schneider Electric and Black and Veatch, the microgrid is powered by 1.8 MW of solar energy, 3.2 MW of LFG electricity and 6.45 MW from a natural gas/diesel power plant. The microgrid is monitored and controlled from a newly built Energy and Water Operations Center, which hosts all the utility and energy control systems for the base.

The microgrid prioritizes the use of renewable energy, which provides about 50 percent of the base’s power consumption. The generators at the natural gas/diesel power plant were sized to cover critical loads in case of a primary grid failure but renewables were included to make the microgrid less reliant on fossil fuels. Assuming all resources are available, the incorporation of onsite renewable power provides the microgrid the opportunity to power mission critical areas for up to 21 days. MCAS Miramar also plans to integrate lithium-ion battery storage by 2024 through a California Energy Commission grant to help supplement energy usage during peak times, support the renewables in island mode and further reduce the need for fossil fuels.

In June 2020, the installation proved that the microgrid can power all the base’s critical operations, including more than 100 buildings and its entire flight line, while also confirming functionality through various stress tests. As of 2023, the base has performed more than 17 base-wide power outage tests with microgrid operation, practicing and preparing for the future.

In addition to supporting the base’s own operations, the microgrid can support the local grid as needed. During heat waves in the summers of 2020, 2021 and 2022, MCAS Miramar provided emergency support through demand reduction from the microgrid to San Diego Gas & Electric during rolling power outages, which allowed the utility to provide continuous power to thousands of homes that otherwise would have been affected by blackouts.

Criteria:

Project is in an area with favorable energy storage policies such as behind-the-meter storage or net metering for grids that are connected to larger grid systems.

Pros:

Energy storage can supplement traditional power resources and serve as a backup power source during outages.

Cons:

Microgrid technologies are relatively new and are evolving, so there is a lack of standards and regulations regarding the best ways to synchronize them with the main power grid and inconsistency as to whether they should be classified as electrical utilities. These complications can make it unappealing to develop microgrids due to uncertainty and potentially high costs.
Utilities may be resistant to microgrid construction as this may cut into their revenue.
Microgrids can also face challenges related to management, safety and protection.

Economic Considerations:

Battery storage costs are $550 to $560 per kilowatt-hour (kWh) for total installed cost and $83 per kilowatt (kW) per year in operation and maintenance costs.¹ Projected future installed costs are $94 per kWh in 2024 and $62 per kWh in 2030.¹
Additional costs are for smart interconnection, controllers, and other infrastructure.
- Controller costs range from $6,200 to $470,000 per megawatt (MW).²
- Infrastructure (distribution system, information technology communications upgrades, metering) can range from 1 to 38 percent of total microgrid costs.²

More Information:

Microgrids, U.S. Department of Energy (DOE)/National Renewable Energy Laboratory (NREL)
Microgrids for Energy Resilience: A Guide to Conceptual Design and Lessons from Defense Projects, U.S. DOE/NREL
Phase I Microgrid Cost Study: Data Collection and Analysis of Microgrid Costs in the United States, U.S. DOE/NREL
Community Microgrids: A Guide for Mayors and City Leaders Seeking Clean, Reliable and Locally Controlled Energy, Microgrid Knowledge
Webinar: Landfill Gas Electricity Power Purchase Agreement Ending Soon? Learn What You Can Do, EPA LMOP

References

¹NC Clean Energy Technology Center. Energy Storage, Electric Vehicles & EV Charging. 21^st Century Strategic Direction: Comprehensive Study and Key Considerations. March 31, 2020. https://nccleantech.ncsu.edu/wp-content/uploads/2020/05/21st-Century-Integrated-Electric-Resource-Study-Final-DO-NOT-EDIT-MOC-.pdf.

²Giraldez, Julieta, et al. U.S. Department of Energy. National Renewable Energy Laboratory. Phase I Microgrid Cost Study: Data Collection and Analysis of Microgrid Costs in the United States. NREL/TP-5D00-67821. October 2018. https://www.nrel.gov/docs/fy19osti/67821.pdf.

³U.S. EPA. LMOP Landfill and Landfill Gas Energy Project Database. July 2021. https://www.epa.gov/lmop/lmop-landfill-and-project-database.

⁴Purtee, Ray. City of San Diego. Miramar Landfill Gas Utilization Enabling the First Green Marine Corps Facility. January 23, 2014. https://www.epa.gov/sites/default/files/2016-05/documents/27_purtee.pdf.

⁵Dockery, Col. Charles. Opinion: Miramar’s Innovative Microgrid Supports National Defense and Our San Diego Neighbors. June 17, 2021. https://timesofsandiego.com/opinion/2021/06/17/miramars-innovative-microgrid-supports-national-defense-and-our-san-diego-neighbors/ . Accessed December 17, 2021.

⁶Wood, Elisa. Microgrid Knowledge. Miramar Microgrid to Demonstrate One Solution to World’s Waste Problem. February 8, 2019. https://www.microgridknowledge.com/google-news-feed/article/11429923/miramar-microgrid-to-demonstrate-one-solution-to-world8217s-waste-problem. Accessed June 30, 2023.

⁷Howland, Ethan. Microgrid Knowledge. Schneider Electric, Black & Veatch Finish Miramar Microgrid. March 16, 2021. https://www.microgridknowledge.com/editors-choice/article/11428191/schneider-electric-black-veatch-finish-miramar-microgrid. Accessed June 30, 2023.

⁸Wasco, Mick. Marine Corps Air Station Miramar. Email correspondence. March 17, 2023.