Solar Microgrid Retrofit Analysis Greenbelt, Prince George’s County Maryland Project Proposal Izabelle Cummings, Chloë Kesey, Kelly Long, Wesley Schriver Advisor: Dr. Peter May Table of Contents Project Scope The proposed focus areas and the partners involved Case Studies Projects to consider as examples of microgrid implementation Solar Implementation Design considerations, calculations, and estimations Energy Storage Considerations Possible energy storage options Resiliency Hubs Areas of refuge and resources in times of need and on a daily basis 2 3 4 Future Considerations Criteria that need further analysis in future phases 5 Areas of Interest Areas of Interest Location History ● Greenbelt is a suburb of Washington, D.C., located in Prince George’s County ● Modeled after 19th century English garden cities, Greenbelt took its name from the belt of green forestland at its perimeter ● Designed to provide work for the unemployed, and affordable housing for low-income workers. Location History ● Franklin Park Apartments have a total of 2,900 units and were built in 1970 ● Hanover Park Apartments have a total of 342 units and were built in 1962 PALS, UMD’s Partnership for Action Learning in Sustainability program, has relationships with local governments and nonprofit clients to bring real-world projects to its students. This project of UMD PALS and Prince George’s County’s Department of Environment applied environmental justice concepts and solar energy technology to two large apartment complex communities in Greenbelt, Maryland. PALS and DOE The Brooklyn Microgrid Overview The Brooklyn Microgrid (BMG) is a local solar energy market between NYC residents and businesses. It connects those with abundant solar panel energy (prosumers) and community members who want to purchase that energy (consumers). ● Established April 2016 ● LO3 Energy is the parent company ● Connects three distribution grids: Borough Hall, Park Slope, and Bay Ridge ● Uses the BMG app to facilitate solar auction—buying and selling (BMG, 2019) (Mengelkamp et al., 2017) The Brooklyn Microgrid Microgrid Methodology ● TransActive Grid Smart Meter (TAGSM) in the existing utility meter and fuse box runs energy to the traditional grid, operated by Con Edison, Inc., “to supply the physical energy flow and only decouples the physical microgrid in emergency situations” ● Information from the TAGSM is transferred to blockchain accounts, which uploads to the TransActive blockchain architecture to update the energy market information to buy and sell electricity ● Consumers virtually pay their producing neighbors feeding the distribution grid with renewable energy only through blockchain (Mengelkamp et al., 2017) The Brooklyn Microgrid (Mengelkamp et al., 2017) The Brooklyn Microgrid (Mengelkamp et al., 2017) The EcoBlock Overview The EcoBlock project is developing a prototype block in Oakland, CA that expands community resilience by retrofitting various aspects of the infrastructure. The data from this project will be available for replication in urban areas around the world. (Barr et al., 2019) http://www.youtube.com/watch?v=vYjGvG9JAPc The EcoBlock Microgrid Methodology ● Existing PG&E assets for distribution of AC power—telephone poles, transformers, meters, and other equipment—will be retained ● Three scenarios for the provision of AC and DC power in the EcoBlock ○ Scenario 1: PV systems are tied to a block-scale AC microgrid with a shared storing FESS providing AC power to houses and charging the flywheel; the flywheel will provide power during an outage ○ Scenario 2: PV systems are tied to a block-scale DC microgrid and shared FESS; using existing AC circuits and equipment in homes to provide power in an outage; possible net energy metering ○ Scenario 3: PV systems and DC appliances are tied to a block-scale DC microgrid which is connected to the FESS and EV chargers; exports power to utility grid; provides DC power during outages with a bidirectional converter (drawing and sending to grid) (Barr et al., 2019) ★ Storage system ○ Use Amber Kinetics ○ Arranged in a row underground 30 x 8 ft. ○ Connected in parallel electric circuit to increase output The EcoBlock (Barr et al., 2019) The EcoBlock (Barr et al., 2019) Safety Design Efficiency In these conditions, Prince George’s County requires 36” fire pathways consider roof obstructions and aesthetics tree shading is an important factor Things to Consider Constraints and Standards Commercial Panel Dimensions Commercial Panel Wattage Module Spacing Google Earth Pro Panel Energy Efficiency 78” x 39” (6.6’ x 3.25’) 350W 1” Date of satellite is 10/2021 and eye altitude ~350-550’ 20% (css.umich.edu) AutoCAD Rendering Example Modules Fire Pathways (36”) Outlines/Obstruction s Project Outcomes Number of Panels 49,937 commercial solar panels Roof Area (Ac) 28.16 acres Roof Area (SqFt) 1,226,730 square feet Energy Output (W) Energy Output (MW) 17,477,950 Watts 17.48 Mega Watts Panel Area 1,054,919.12 SqFt, 24.22 acres 86% Potential Solar Installation Companies ● High-efficiency commercial and residential solar panels ● Located in the DMV ● Global solar panel manufacturer ● www.us.sunpower.com ● Solar energy development firm ● Have experience working on large-scale solar projects in the DMV ● www.solsystems.com ● Residential and commercial solar panel installer ● Strong presence in the DMV area ● Offer a range of solar panels and other renewable energy solutions ● www.directenergy.com http://www.us.sunpower.com/ http://www.solsystems.com/ 9,025,613.38 kWh 9,025.61 MWh Estimated Annual Energy Production Estimated Total Cost $18,769,011.21 power of commercial unit (kW) 0.35 number of units 49,937 peak sunlight hours (365) 2,582 total kW output 17,477.95 kWh rating of system 45,128,066.9 cost of system $28,489,058.50 state tax credit 2.6 cents per kWh federal tax credit 30% cost reduction from state credit $1,173,329.74 cost reduction from federal credit $8,546,717.55 final cost $18,769,011.21 Equivalent to CO2 emissions from: 719,736 Gallons of gasoline 7,164,831 Pounds of coal Tanker trucks of gasoline 1,245 Homes’ electricity use for one year 1,423 Gasoline powered passenger vehicles driven for one year 778,062,135 smartphones charged 84.7 http://www.epa.gov/ Equivalent to greenhouse gas emissions avoided by: 2,213 Tons of waste recycled instead of landfilled 242,868 Incandescent lamps switched to LEDs 1.8 Wind turbines running for a year www.epa.gov http://www.epa.gov/ Equivalent to carbon sequestered by: 42.4 105,763 Tree seedlings grown for 10 years 7,628 Acres of US forests in one year Acres of US forests preserved from conversion to cropland in one year www.epa.gov http://www.epa.gov/ Importance of Community Solar What is Community Solar? “The U.S. Department of Energy defines community solar as any solar project or purchasing program, within a geographic area, in which the benefits of a solar project flow to multiple customers such as individuals, businesses, nonprofits, and other groups” (Solar, n.d.) Benefits of Community Solar ● Buy/lease a portion of solar panels to receive electric credit on bill ○ Save money with renewable energy ○ Maryland passed specific legislature in 2017 to promote this accreditation (Maryland, 2021) Interconnectedness within the community as they work together to supply power to one another Improve the utility and customer relationship ● ● Residential Clean Energy Grant Maryland’s Residential Clean Energy Grant Program— provides a rebate as an incentive for Maryland homeowners to purchase and install eligible renewable energy generating systems at their residences. An anticipated total of $3,600,000 is available from the Strategic Energy Investment Fund to fund this program. Clean Energy Technology Eligible System Capacity Range Rebate Amount Solar Photovoltaic Minimum 1kW-DC 1,000$ Residential Community Solar Grant Residential Community Solar Grant— allows Maryland residents to purchase energy subscriptions from community solar arrays. The grant is a monetary incentive for residents who wish to purchase the energy benefits of the array. Low- and moderate-income residents who subscribe to a community solar array under an ownership model are incentivized at a higher rate than other subscribers. Non-Low/Moderate Income Category $100/kW Maximum incentive size is equal to 100% of the annual energy use divided by 20 kW Low/Moderate Income Category $300/kW Maximum incentive size is equal to 100% of the annual energy use divided by 20 kW Regulations Rooftop solar array projects require two permits— • A building permit to attachment solar panels to the rooftop • An electrical permit to connect to the building's electrical service Permit Application and Filing Fee Payment The permits may be issued by lot or interconnection point, not individual addresses of all units underneath the roof Regulations ● After building permit fees are paid and the project plans are approved, a licensed master electrician can obtain the electrical trade permit. ● PV solar array system plans must be designed, stamped, and sealed by a Maryland Professional Engineer. ● Architectural plans can be stamped by the structural engineer of record if no proposed changes are being made to the building’s architecture and included schematics are of a structural nature (i.e., array plan, connection details, roof framing plan, and other structural members). Building Code ● 2018 NFPA1 provides a comprehensive, integrated approach to fire code regulation and hazard management. Relevant to solar panels, e.g., all new electrical wiring, fixtures, appliances and equipment shall be installed according to NFPA70. ● Prince George’s County Subtitle 4, Subtitle 9, and Subtitle 11: ○ Subtitle 4: Building, ○ Subtitle 9: Electrical ○ Subtitle 11: Fire Solar System Installation Code Requirements Electrical Code ● National Electrical Code (NFPA 70, National Electric Code, Article 690): Emergency system(s) overcurrent protective devices (OCPDs) shall be selectively coordinated with load-side OCPDs. ○ Coordination is selected by a licensed professional engineer engaged primarily in the design, installation, or maintenance of electrical systems. Solar Energy System Installation Code Requirements Health Considerations • Hazardous Materials • Electromagnetic Fields (EMF) • Electric Shock and Arc Flash Health Considerations Hazardous Materials ● PV panels consist of glass, polymer, aluminum, copper, and semiconductor materials that can be recovered and recycled at the end of their useful life. ● Some solar panels contain tiny amounts of lead. ○ So the electrodes can make effective electrical contact with the PV cell, other materials (glass frit) are mixed with silver alloy and heated to etch the metals into the cell. This glass frit contains a small amount of lead oxide. General consensus is that solar panels are not a threat to public health ● Health Considerations Electromagnetic Fields ● PV systems don’t emit any material during their operation but do generate electromagnetic fields (EMF). ● EMF produced by electricity is non-ionizing radiation, i.e., the radiation has enough energy to move atoms in a molecule (experienced as heat), but not enough to remove electrons from an atom or to damage DNA. ● Most people are exposed to EMF in our daily lives without negative health impact. ● Negative health impacts have been found from the EMF produced in a solar array. Energy Storage Considerations Storing and Moving the Energy General Solar Energy Storage ● The best way to store solar energy is in a BESS— Battery Energy Storage System (Stein, 2023) ○ One or more batteries that reserve the system produced energy (renewables, grid connection, etc.) until needed ○ Includes components such as inverters, control components, sensors, and modules ● Battery options ○ Lithium-Ion ○ Flow ○ Flywheels (FESS) https://www.microgridknowledge.com/sponsored/article/33002666/pxise -energy-solu tions-finding-that-battery-size-and-roi-sweet-spot https://ambe rkinetics.com/installation/utility-of-the-future/ http://www.microgridknowledge.com/sponsored/article/33002666/pxise-energy-solutions-finding-that-battery-size-and-roi-sweet-spot http://www.youtube.com/watch?v=8X2U7bDNcPM Solar Energy Storage Safety Current Hazards Thermal Runaway • Rapid uncontrolled heat energy released from a battery cell unable to dissipate • Leads to battery fire/explosion; produces toxic fumes and gases • Stored energy can’t discharge, may reignite fires or shock first responders Battery Failure • Facilitates thermal runaway • Thermal and electrical abuse such as excessive external heating or overcharging • Mechanical abuse such as dropping, crushing, or destruction to integrity of the battery (rodents, etc.) facilitate thermal runaway https://www.wattalps.com/thermal-runaway-propagation- and-mitigation/ Solar Energy Storage Safety Current Safety Measures Regulations • Must follow FERC regulations (Federal Energy Regulatory Commission), the DOE, and other state regulations (Petrova, 2021) Maryland DNR Best Practices • 10-foot buffer around BESS from combustible vegetation • Utility lines should be placed underground • Need a 7-foot tall, self-locking fence around the BESS • Design must have specialized HVAC, interpreting devices, high-heat tolerant enclosed containers, etc. (MDDNR, 2022) Solar Energy Storage Safety Current Safety Measures Design Mechanisms • PCS: Power Conversion System • BMS: Battery Management System • S.D.: Smoke Detector (Rosewater et al., 2020) Goals for Energy Storage Provide reliable local electricity • reduce resident electric bills • supply energy in times of crisis/emergencies Create a more self-sustaining community • introduce a resiliency hub • enable economic and environmental benefits • work with macrogrid/municipal electric utilities Facilitate community approval and involvement • community centered; community consulted decisions • visually appealing and not obstructing • responsive to changing loads Potential BESS Companies • US-based Global Utility Company • Experienced and interested in developing o microgids; single-source capable • More than 180 MW BESS in operation the US • https://www.nexteraenergy.com/company/work/battery- storage.html • GE Renewable Energy Department • Provide reservoir solutions for commercial, o residential, industrial; mention microgrids • https://www.ge.com/renewableenergy/hybrid/bat tery-energy- storage • BESS Manufacturer • Specialize in energy storage with pre engineered products • Offer a 500 kW BESS storage unit • https://agreate.com/microgrid-battery-energy-storage- systems/ http://www.nexteraenergy.com/company/ http://www.ge.com/renewableenergy/hybrid/bat Potential FESS Companies • Long-duration Flywheel Energy • Storage System Manufacturers • Numerous installations in the US and different countries • Located in California • Installed in the ground • https://amberkinetics.com/ • Carbon Fiber Flywheel Manufacturers • 400 flywheels installed • Located in Massachusetts • Ability to move 5,000 MWh through the machine in a lifetime • https://beaconpower.com/carbon- fiber- flywheels/ Centralized Installation (East Microgrid) Centralized Installation (West Microgrid) Decentralized Placement Considerations Potential space for a decentralized design ○ Each complex or local complex divisions could have a battery storage system ○ Similar to dumpster fencing, the BESS or FESS is in a fenced zone Pros Cons Prevent complete system destruction, unlike centralized systems More ground space to cover maintenance-wise Uses available space and prevent further habitat destruction Complications with connecting the grid together Ease of maintenance Could cost more to install Resilience Hubs Background and Potential Hub Locations What is a Resilience Hub? Everyday A central point for a community to gather, every day or during disaster when help is needed the most. Planning for the future and collaborating for the betterment of the community Disruption A hub for internal and external communication, leading the way for response Recovery A safe house for a community, host volunteers and emergency aid Baltimore as an Example Baltimore’s Disaster Preparedness Plan Partnered with Baltimore’s - Office of Sustainability (BoS) - Office of Emergency Management (OEM) - Department of Health (BCHD) Provide districts with solar power and battery back-up charging stations Importance of Recovery Hub When disaster strikes, a safe place for the community Provide - reliable energy, to charge essentials - general supplies - food - water - dry, temperature-controlled space to store perishable medicines - car charging Host - emergency and recovery personnel - supplies distribution - collaborative community events Ideal Locations for Resilience Hubs West Microgrid East Microgrid Greenbelt Middle School Eleanor Roosevelt High School Council Districts pgcountymd.gov WEST EAST https://www.princegeorgescountymd.gov/DocumentCenter/View/41415/CouncilmanicCountywide Benefits of the Ideal Locations Real Estate Proximity to Grids Minimal distance from grids keeps efficiency high Schools have space for community meetings or emergency shelter Emergency Care Both locations within a mile of a hospital Transport Both locations are schools, which have access to bus routes Future Considerations • Tap into macro grid utility or island microgrid • Common area powering; won’t pay for those costs (benefit owners) and tax credits (public good) • To prevent gentrification, enforce rules to keep rent at the same rate • BESS/FESS pricing is based on actual implementation • Split Resilience Hubs, share east and west locations between Districts 3 and 4 Thanks! Any questions? This presentation template was created by Slidesgo, and includes icons by Flaticon and infographics and images by Freepik https://bit.ly/3A1uf1Q http://bit.ly/2TyoMsr http://bit.ly/2TyoMsr http://bit.ly/2TtBDfr References About Greenbelt, Maryland, the vibrant city with new deal roots. Greenbelt Online. (2020, December 27). https://www.greenbeltonline.org/greenbelt/ Barr, Z., Bourassa, N., Bowie, J., Brown, R., DeCuir, N., Diamond, H.J., Dryden, A., Elkind, E., Fraker, H., Fu, W., Guy, E., Hamilton, D., Lamm, T., Nicholson, M., Rainer, L., Robertson, S., Scott Thomson, C., Tome, E., Traber, A. (2019). Accelerating the Deployment of Advanced Energy Communities: The Oakland EcoBlock. California Energy Commission. Publication Number: CEC-500-2019-043 . http://coeecoblock.wpengine.com/wp-content/uploads/2019/07/CEC-500-2019-043.pdf BMG. (2019). Brooklyn Microgrid: About. Brooklyn Microgrid. https://www.brooklyn.energy/about Cleveland, T. (2017). Health and Safety Impacts of Solar Photovoltaics. NC Clean Energy Technology Center. https://nccleantech.ncsu.edu/wp-content/uploads/2018/10/Health-and-Safety-Impacts- of-Solar-Photovoltaics-2017_white-paper.pdf Community Solar Grant. Maryland Energy Administration. (n.d.). https://energy.maryland.gov/residential/Pages/Community- Solar.aspx#:~:text=Residential%20Community%20Grant%20Solar&text=The%20grant%20provides%20a%20monetary%20incentive%20for%20Maryland%20residents%20who,higher%20rate% 20than%20other%20subscribers. Guidelines for permitting rooftop photovoltaic (PV) solar array systems. (n.d.). https://www.princegeorgescountymd.gov/DocumentCenter/View/42885/DPIE-Guidelines-for-Permitting-Rooftop-PV- Solar-Array-Systems-PDF Maryland Community Solar. (2021). Why is community solar is growing in Maryland?. https://mdcommunitysolar.org/why-is-community-solar-growing-in-maine/ MDDNR. (2022). Siting and Safety Best Practices for Battery Energy Storage Systems. Maryland Power Plant Research Program. https://dnr.maryland.gov/pprp/Documents/PPAD-BESS-2022-01- Report.pdf Mengelkamp, E., Garttner, J., Rock, K., Kessler, S., Orsini, L., Weinhardt, C. (2017). Designing microgrid energy markets A case study: The Brooklyn Microgrid. Applied Energy 210 (2018) 870-880. https://doi.org/10.1016/j.apenergy.2017.06.054 NFPA. (2020). Energy Storage Systems Safety Fact Sheet. National Fire Protection Association. https://www.nfpa.org/~/media/Files/Code%20or%20topic%20fact%20sheets/ESSFactSheet.pdf Petrova, A. (2021). Efficient Energy Management and Energy Saving with a BESS (Battery Energy Storage System). Integra Sources. https://www.integrasources.com/blog/energy-management-and- energy-saving-bess/ http://www.greenbeltonline.org/greenbelt/ http://www.greenbeltonline.org/greenbelt/ http://coeecoblock.wpengine.com/wp-content/uploads/2019/07/CEC-500-2019-043.pdf http://www.brooklyn.energy/about http://www.princegeorgescountymd.gov/DocumentCenter/View/42885/DPIE-Guidelines-for-Permitting-Rooftop-PV- http://www.princegeorgescountymd.gov/DocumentCenter/View/42885/DPIE-Guidelines-for-Permitting-Rooftop-PV- https://doi.org/10.1016/j.apenergy.2017.06.054 http://www.nfpa.org/~/media/Files/Code%20or%20topic%20fact%20sheets/ESSFactSheet.pdf http://www.nfpa.org/~/media/Files/Code%20or%20topic%20fact%20sheets/ESSFactSheet.pdf http://www.integrasources.com/blog/energy-management-and- http://www.integrasources.com/blog/energy-management-and- References Ramasamy, V., Zuboy, J., O’Shaughnessy, E., Feldman, D., Desai, J., Woodhouse, M., Basore, P., & Margolis, R. (2022). U.S. Solar Photovoltaic System and Energy Storage Cost Benchmarks, with Minimum Sustainable Price Analysis: Q1 2022. https://doi.org/10.2172/1891204 Rosewater, D., Lamb, J., Hewson, J., Viswanathan, V., Paiss, M., Choi, D., Jaiswal, A. (2020). Grid-scale Energy Storage Hazard Analysis & Design Objectives for System Safety. Sandia National Laboratories. Report Number, SAND2020-9360. https://www.osti.gov/servlets/purl/1662020 Solar Energy Technologies Office. (n.d.). Community Solar Basics. U.S. Department of Energy. https://www.energy.gov/eere/solar/community-solar-basics Stein, Z. (2023). Battery Energy Storage Systems (BESS). Carbon Collective. https://www.carboncollective.co/sustainable-investing/battery-energy-storage-systems-bess The Baltimore City Community Resiliency Hub Program: Baltimore Office of Sustainability. Baltimore Office of Sustainability |. (2022, September 2). https://www.baltimoresustainability.org/baltimore-resiliency-hub-program/ Updated 2022 redistricting map pdfs - download at no cost : Prince george’s county, MD. Updated 2022 Redistricting Map PDFs - download at no cost  | Prince George’s County, MD. (n.d.). https://www.princegeorgescountymd.gov/4347/Updated-2022-Redistricting-Map-PDFs---do http://www.osti.gov/servlets/purl/1662020 http://www.osti.gov/servlets/purl/1662020 http://www.energy.gov/eere/solar/community-solar-basics https://www.carboncollective.co/sustainable-investing/battery-energy-storage-systems-bess http://www.baltimoresustainability.org/baltimore-resiliency-hub-program/ http://www.baltimoresustainability.org/baltimore-resiliency-hub-program/ http://www.princegeorgescountymd.gov/4347/Updated-2022-Redistricting-Map-PDFs---do http://www.princegeorgescountymd.gov/4347/Updated-2022-Redistricting-Map-PDFs---do Table of Contents Project Scope Energy Storage Case Studies Solar Implementation Considerations Resiliency Hubs Future Considerations Areas of Interest Location History Location History Overview Microgrid Methodology Safety Design Efficiency Constraints and Standards AutoCAD Rendering Example Project Outcomes Number of Panels Roof Area (Ac) Roof Area (SqFt) Energy Output (W) Energy Output (MW) Equivalent to CO2 emissions from: 719,736 7,164,831 1,245 1,423 778,062,135 2,213 Equivalent to carbon sequestered by: 105,763 Importance of Community Solar What is Community Solar? Residential Clean Energy Grant Residential Community Solar Grant Building Code Electrical Code Hazardous Materials Electromagnetic Fields Energy Storage Considerations General Solar Energy Storage Potential FESS Companies Decentralized Placement Considerations Resilience Hubs What is a Resilience Hub? Everyday Disruption Recovery Baltimore as an Example Importance of Recovery Hub When disaster strikes, a safe place for the community Ideal Locations for Resilience Hubs West Microgrid East Microgrid Council Districts Benefits of the Ideal Locations Proximity to Grids Real Estate Transport Emergency Care Future Considerations Thanks!