How does Module Tracking for Agrivoltaics Differ from Standard Photovoltaics? Performance & Technoeconomic Implications

Abstract

Spatial-temporal sharing of sunlight between solar modules and crops needs to be designed optimally in agrivoltaics (AV). For AV with fixed module tilts, the sunlight balance is governed through the spatial density and elevation of the modules which cannot be manipulated after the installation. For flexible food-energy balancing across various seasons and crop rotations, modules with single or dual axis mobility can be best suitable. AV tracking must be geared towards ensuring a desired sunlight balance that may depend on many factors including the crop type, module array density, socio-economic factors, and local policies. Here, we explore single axis customized tracking (CT) for the mobile AV using a techno-economic model that incorporates design parameters including crop's shade sensitivity, module to land area ratio, and module types, as well as the economic parameters including soft and hardware costs for modules, feed-in-tariff, and crop income. CT is implemented through standard tracking that tracks the sun around noon hours and its orthogonal, i.e., anti-tracking around sunrise and sunset. We evaluate the optimal CT schemes that can maximize economic performance while ensuring the desired food-energy yield thresholds. Economic feasibility for AV is evaluated in terms of the ratio (ppr) of the price for the module system customizations to the performance benefit due to the crop income. A case study for Punjab, Pakistan shows that CT schemes for moderate shade sensitive crops and typically dense AV module arrays can require 30 to 40 percent increase in the reference FIT to ensure the food-energy yield threshold of 80 percent relative to standalone food-energy farms for high and low value crops, respectively. CT schemes for a lower crop yield threshold of 70 percent require the corresponding increase in FIT to 10 to 20 percent, respectively.