Experimental and numerical investigation of spectrally selective radiative regulation glass and a checkerboard photovoltaic layout for microclimate regulation in photovoltaic greenhouses

The photovoltaic greenhouse is an important pathway for realizing “agrivoltaics” and promoting the green transformation of facility agriculture. However, intense solar radiation in summer easily leads to indoor heat accumulation, which substantially increases cooling energy consumption. Traditional photovoltaic greenhouses mostly adopt centralized photovoltaic arrangements, resulting in uneven light distribution and local heat accumulation. Therefore, this paper proposes a spectrally selective radiative regulation glass and investigates its capability to modulate greenhouse microclimate and cooling effect by regulating different wavelength bands of solar radiation at the laboratory scale. The spectrally selective glass ensures high transmittance of visible light to meet crop photosynthetic requirements while effectively blocking thermal radiation in the near-infrared band. Meanwhile, the checkerboard dispersed arrangement of photovoltaic modules improves indoor light uniformity while achieving clean power generation and energy saving. Combined with the established outdoor test platform, the influence laws of greenhouse microclimate are studied, and the comprehensive performance of the combined regulation approach is evaluated. Within the scope of this study, experimental and numerical results show that the daytime peak air temperature is reduced by 6.3 °C and the peak soil temperature by 5.3 °C compared with the plain-glass greenhouse without PV. The maximum indoor PPFD reaches 1295 μmol·m −2 ·s −1 , which is above the light-saturation level of most horticultural crops. This laboratory-scale study provides preliminary experimental and numerical evidence for the regulation of the greenhouse microclimate, and serves as a reference for subsequent scale-up of the agrivoltaic technology.