Techno-economic evaluation of different agri-voltaic designs for the hot arid ecosystem India

Abstract

The rising trend of solar PV generation from ground based installations has led to competition for land between agriculture and PV generation. The solution to this challenge lies in the agri-voltaic system (AVS). The AVS systems allows agricultural activities on land while provides opportunity for PV generation and thus returns additional income from land. Therefore, the Governments of many countries e.g. Japan, France, USA, South Korea, and China have already introduced policies for installation of AVS on agricultural land. Following this trend, policy to install AVS in farmers field has also been launched in India under the national level scheme called KUSUM (Kisan Urja Suraksha evam Utthan Mahaabhiyan) targeting for energy security and upliftment campaign for farmers. Under the scheme, subsidy is gurranted for installation of PV power plants in farmers field with a capacity between 0.5 and 2 MWp and on-grid net metering connection of the PV power plant. After announcement of the scheme, there has been increasing interests for installation of AVS by farmers, however, limited knowledge on techno-economic performance of the system, field scale installations of it has been hindered. In the present study, techno-economic analysis of different designs of AVS systems (105 kWp) established at ICAR-Central Arid Zone Research Institute has been evaluated with several combinations of rainfed and irrigated crops. Field performance of the AVS system of 105 kWp has been used to extrapolate cost and returns for 520 kWp system, which lies in the range of KUSUM target. Five AVS designs were considered in the study: extrapolated into 520 kWp AVS and compared theoretically with the price and returns of a photo-voltaic ground-mounted (PV-GM) plant the same capacity. Among five designs of PV arrays in the AVS, the one-row full density photovoltaic array with irrigated brinjal recorded the highest combined net returns of PV + crop components followed by rainfed snap melon. Based on the highest returns per hectare basis, the economic analysis of AVS design for rainfed and irrigated crops is compared to PV-GM. The higher values of life cycle benefit (LCB) could lead to higher net present worth (NPW) of AVS over PV-GM. The higher values of internal rate of return (IRR) in AVS lead to quicker repayment of investment cost as indicated by the pay-back period (PBP), which is shorter by 0.5 and 1.14 years in AVS one row PV array in rainfed and irrigated as compared to PV-GM (8.61 years). Moreover, the one row PV array with irrigated had the lowest Levelized cost of electricity generation (LCOE) (INR 3.17 kWh−1), which is much lower than the prevailing electricity tariff (INR 5.0 kWh−1). Hence, it is inferred that crop production can be very economical for an AVS. AVS technology shows flexibility up to 6% escalation in cost with no escalation in returns, as is indicated by sensitivity analysis. One row full density with irrigated is found the best system based on sensitivity analysis and economic feasibility. The economic analysis of AVS designs in this study is similar to the cost of other PV systems worldwide. Therefore, all PV systems analyzed represent a relatively safe investment.