Economic and feasibility analysis of brownfields into brightfields by solar energy

Abstract This study evaluated the costs and feasibility of building photovoltaic (PV) energy systems on brownfields in four localities in Taiwan. Brownfield remediation was assessed as ex situ excavation, in situ physicochemical treatment, and phytoremediation. The localities in tropical Southern Taiwan would have a higher feed‐in tariff revenue (US$0.1750 kWh–1) due to a higher daily power generating efficiency from sunlight. The capital cost including the PV modules would be approximately US$27.1–US$440 million, but the 20‐year operation and maintenance costs would be much lower. The residual value of the PV systems would be significant (US$0.03–$4.7 million) if the systems are recycled at the end of their lifetime. The total revenues from building PV systems on remediated brownfields would be US$463 241–$7 597 138, with a payback period of less than 13 years. The benefit/cost ratios of the PV systems would be between 1.26 and 1.86 depending on the remediation costs. The payback period would be extended to 16 years with a US$0.61 million ha–1 net present value if the brownfields are remediated by phytoremediation. The sensitivity analysis found that the capital costs, feedback fund, and daily power generating efficiency would be US$343 097 for every 1% of the total revenue. It is worth building a PV system if the cost of land is higher than the net present value of the PV system.