A feasibility analysis for a cable–mounted photovotaic array on Cummings Road landfill, Eureka, CA

Humboldt Waste Management Authority maintains the Cummins Road Landfill two miles east of Eureka, CA. As of this writing, the only current work that is performed on the landfill is to control releases of methane and leachate and cap areas of the landfill that, at present are not covered. The goal of this study was to identify whether or not a photovoltaic array on the landfill could offset electricity costs for HWMA, both on site and at other facilities that they own. This project includes both an economic and technical feasibility analysis in order to determine what financial benefit could be realized and if the system could be constructed on the site given the particular constraints of construction that exist on the landfill. The proposed system would be located in two separate areas on the landfill using unique cable mounting method, and direct current electricity generated by the solar arrays would be converted to alternating current power and then stepped up to a higher voltage using a transformer. It would then be conveyed to the lower area of the site where it would be interconnected with the utility power. The total energy production from the array was found to be 522 MWh/year, with a max peak power of 653 kW for the monocrystalline system. The findings from the study showed that the economics were favorable for both monocrystalline and polycrystalline systems given that the NPV payback is less than six years for both. The NPV calculation was performed assuming a 6% nominal discount rate, 4% interest rate, 3% annual electricity escalation rate and no incentives. The technical study found no current roadblocks for the system, but further analysis is needed regarding soil erosion, wire routing, grid-intertie infrastructure and wind loading.