Niebylski, Christopher R.

DOE OSTI2024

Power Supply Options for the Marpi Landfill, Saipan: Comprehensive Feasibility Study

The Marpi Landfill (“Marpi” or “the landfill”), located on the northern end of the island of Saipan in the Commonwealth of the Northern Mariana Islands (CNMI), is powered by a single on-site diesel generator that only operates when the landfill is open and staffed. The project team, composed of representatives of the Department of Public Works and the Office of Planning and Development (OPD), aspires to provide the Marpi Landfill with 24-hour power availability despite its remote location to increase the use of sustainable energy and to ensure environmentally compliant landfill operations. This is consistent with the sustainable development goals documented in the 2021–2030 Comprehensive Sustainable Development Plan (OPD 2021), including Goal #12 (ensure environmentally compliant waste management facilities) and Goal #7 (renewable energy deployment). Further, the CNMI has a 20% target for renewable energy consumption by 2030, as documented in the 2021–2030 Comprehensive Sustainable Development Plan (OPD 2021) and the renewable portfolio standard (Public Law 18-62). To accomplish these goals, the Federal Emergency Management Agency, through its Interagency Reimbursable Work Agreement with the U.S. Department of Energy, funded a feasibility study and follow-up study in 2023–2024 to assess and prioritize power supply options for the landfill. This report combines the results from both feasibility studies.

14 SOLAR ENERGY↗

DOE OSTI2023

Power Supply Options for the Marpi Landfill, Saipan: Feasibility Study

The Marpi Landfill, located on the northern end of the island of Saipan in the Commonwealth of the Northern Mariana Islands (CNMI), is powered by an on-site diesel generator that only operates when the landfill is open and staffed. The CNMI Office of Planning and Development (OPD) aspires to provide the Marpi Landfill with 24-hour power availability despite its remote location and to increase the use of sustainable energy within the CNMI. CNMI has a 20% target for renewable energy consumption, as documented in Sustainable Development Goal #7 in the Comprehensive Sustainable Development Plan (OPD 2021) and the renewable portfolio standard (GPO 2014). To accomplish these goals, the U.S. Department of Energy, through its Interagency Reimbursable Work Agreement with the Federal Emergency Management Agency, funded this feasibility study to assess and prioritize power supply options for the landfill. The availability of solar and wind resources varies seasonally, as does the load. A BESS can help to balance mismatches between generation and load on short (hourly or daily) timescales, but not across seasons. The microgrid scenarios evaluated for Marpi consider options for technology combinations that will both meet the load and utilize available resources, despite the challenge presented by higher loads and lower solar and wind availability during the rainy season, depicted in Figure ES-2. The seven scenarios evaluated are summarized in Table ES-1. Each scenario’s configuration was optimized to include component capacities that reduce capital and operating costs, meet the load, and minimize carbon emissions, as feasible. The costs and levelized cost of energy (LCOE) shown do not assume the use of any grant funding or incentives, although these options were also evaluated. To assist with decision-making, a prioritization matrix (Table ES-3) was created to compare the microgrid scenarios evaluated in this feasibility study according to various stakeholder priorities. The prioritization metrics were chosen based on discussions with OPD and will be finalized through stakeholder feedback. The scenarios were given a score between 1 and 7 for each prioritization metric (the lower the score, the higher the priority), and total scores were calculated using assigned weights based on the relative priority of each metric. The total scores were then ranked to produce a prioritized list of microgrid scenarios based on the metrics most important to the project stakeholders. As shown, scenario 4 (100 kW of solar PV, a 75 kW/300 kWh BESS, and 160 kW of diesel generation) ranks highest.

14 SOLAR ENERGY↗