Life-cycle ecological footprint assessment of grid-connected rooftop solar PV system
Ajay Biswas, Dilawar Husain, Ravi Prakash
Abstract
Solar photovoltaic (PV) power generation system is generally considered to be land-intensive in view of the diffuse nature of solar energy. However, a comprehensive assessment in this regard would involve bio-productive land for all types of resource consumption during the lifespan of the system. This study presents such an assessment for a grid-connected rooftop solar photovoltaic (RSPV) system located in a tropical climate. The life cycle ecological footprint (EFT) methodology has been used to derive the results based on material & energy consumption, water & manpower requirements along with waste disposal. This methodology is illustrated through an existing 1 MWp RSPV system installed at an educational institution in India. The total EFT is evaluated as 22.69 global hectare (gha) per year, out of which the environmental impact of solar PV panels is 76% of the total. The EFT per kWP capacity is 0.454 gha/kWP and the EFT per unit solar panel collector area is 0.074 gha/m2. The EFT of the RSPV system per unit electricity generation is 1.59 × 10−5 gha/kWh. However, considering only emissions from the grid-electricity in India, an approximate reduction potential of ecological footprint through RSPV-based electricity is estimated as 95%.