Persistent site-scale warming associated with solar photovoltaic installations.

Area of Science:

• Environmental Science
• Climate Science
• Renewable Energy

Background:

• Large-scale solar photovoltaic (PV) farms are crucial for meeting energy demands and reducing emissions in semi-arid regions.
• Land-cover transformation by PV farms may disrupt local energy balance and modify near-surface thermal conditions.

Purpose of the Study:

• To verify the hypothesis that solar PV farms alter local thermal conditions in semi-arid desert environments.
• To quantify the impact of PV installations on air temperature, land surface temperature, and radiation balance.

Main Methods:

• Conducted a two-year field experiment in a semi-arid desert region in Inner Mongolia, China.
• Utilized ground-based meteorological observations and Unmanned Aerial Vehicle (UAV)-based thermal mapping.
• Analyzed changes in air temperature, daily temperature range, land surface temperature, net radiation, albedo, and outgoing longwave radiation.

Main Results:

• The PV farm showed a 0.8°C increase in mean air temperature and a 1.9°C reduction in daily temperature range.
• UAV thermal mapping revealed land surface temperature increases of 0.3-4.1°C in PV areas.
• Net radiation increased by 8.3 W m⁻², driven by decreased albedo and increased net shortwave radiation.

Conclusions:

• Photovoltaic installations in semi-arid deserts lead to persistent site-scale warming.
• Altered energy balance, characterized by reduced albedo and increased net radiation, contributes to warming.
• Findings highlight potential microclimatic impacts and environmental trade-offs of PV deployment in dryland ecosystems.