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• Quality of strawberry was improved by solar energy adjusting temperature and light. • Strawberry grew better when the PV modules occupied 25.9% roof of greenhouse. • The suitable light range for strawberry under the shade of PV module was obtained. • Solar combined air source heat pump provides suitable heating for strawberry. Strawberry production is greatly affected by environmental factors, especially temperature and light. A solar greenhouse with opaque photovoltaic (OPV) modules and a solar combined air source heat pump system was built for strawberry production. The aim of this study was to assess the impact of differences in both temperature and light factors caused by OPV modules and solar heating on strawberry growth and quality in a constructed greenhouse. The 'Jingzangxiang' strawberry was selected and planted in the greenhouse. The indoor temperature with the heating system was 5.3–7.3 °C higher than the ambient temperature at the coldest period in the city of Kunming. At noon, the chlorophyll content of the shaded strawberry plants was 1.3 times higher than that of the unshaded plants in sunny weather, and the average shaded photosynthetically active radiation (PAR) was 230 μmol·m−2·s−1 in the greenhouse, where 25.9% of the roof was covered with OPV modules. Under this shading treatment, the optimum light range of PAR for the 'Jingzangxiang' strawberry was 387–437 μmol·m−2·s−1, and the optimum temperature range during the daytime was 20.5–27.4 °C. The largest single strawberry fruit weighed 33.9 g, and the soluble solids content of the shaded strawberry fruit was 16.4%, which was higher than that of the unshaded strawberry samples. Furthermore, the yield of the shaded samples was 1.2 times that of the unshaded samples. In summary, strawberry plants shaded by OPV modules were superior to unshaded strawberry plants in terms of growth, quality and yield. This research provides experimental support and information on the optimal temperature and light ranges for the growth of the 'Jingzangxiang' strawberry in solar greenhouse. [ABSTRACT FROM AUTHOR]

[Display omitted] • Energy assessment of greenhouse is presented based on plant growth requirements. • Mean net photosynthetic rate increases and then drops with coverage area raised. • Daily cooling load reduces by 0.45–1.02 kWh when coverage ratio increases by 10%. • Photovoltaic generation rises by 1.7–3.19 kWh/d when coverage ratio rises 10%. • Coefficient of performance increases and then decrease with coverage areas rising. Photovoltaic (PV) greenhouses are widely used to regulate internal irradiance and air temperature to create optimal climatic conditions for plant growth. Therefore, comprehensive multidomain energy models of PV greenhouses are more likely needed to improve the system performance. However, few studies investigate optical-electrical-thermal characteristics and PV greenhouse evaluation indicators based on crop growth requirements. The aim of this work is to develop coupled optical-electrical-thermal models to assess the energy performance of the PV greenhouse with different PV roof coverage ratios during the summer months. In addition, the models of photosynthetically active radiation (PAR) and net photosynthetic rate (P N) are presented based on the irradiance and temperature of the PV greenhouse to evaluate the dynamic response of crops to interior climate conditions. The models are validated with experiments on the PV greenhouse in Kunming, with a total area of 26.25 m2. The electricity supply and demand systems include PV modules (3.285 kWp), a battery bank (24 kWh), an air–water heat pump (AWHP), and spray combined with fan cooling. Two cooling scenarios are analysed and compared by varying the PV module coverage ratio. Scenario 1 (S.1) is AWHP cooling, and scenario 2 (S.2) is spray combined with fan cooling. The optimum interior temperature and PAR of the PV greenhouse are 22 °C and 300 μmol·m−2·s−1, respectively. The simulations indicate that if the proportion of the PV layout on the greenhouse roof is greater than 20%, the year-round PAR inside the greenhouse will be below the threshold value of 550 μmol·m−2·s−1 at which the strawberry P N is saturated. For every 10% increase in PV roof coverage, the interior air temperature decreases by 0.02–0.56 °C corresponding to a daily cooling load reduction of 0.45–1.02 kWh/d, while the PV generation increases by 1.7–3.19 kWh/d and the maximum electricity consumption of S.1 and S.2 drops by 0.66 kWh/d and 0.52 kWh/d, respectively. Moreover, the high self-consumption-sufficiency balance (SCSB) values show that the PV and battery sizes are 2.22–2.78 kWp (40–50% coverage) and 15.72–15.75 kWh for S.1, and those in S.2 are 1.11–1.67 kWp (10–30% coverage) and 0.66–3.22 kWh. The coefficient of performance (COP) of the system reaches a maximum of 0.45–1.12 at 40% coverage in S.1 and 1.88–3.01 at 10–30% coverage in S.2. When the PV module coverage is 40% in S.1, the levelized costs of electricity (LCOE) and levelized costs of cooling (LCOC) are the lowest at 0.0760USD/kWh el and 0.0693USD/kWh c. Similarly, the lowest LCOE and LCOC of S.2 are 0.0306USD/kWh el and 0.0210USD/kWh c, as the PV module coverage is 30%. The study will be beneficial for applying photovoltaic modules, battery banks, and cooling technologies in the greenhouse, especially considering the dynamic crop response to internal climates and the energy performance assessment. [ABSTRACT FROM AUTHOR]