Abstract: This study aims to synergistically enhance the multi-spectral utilization efficiency in greenhouses, in order to alleviate the conflict between thermal energy collection and plant lighting. A transparent heat-collecting structure was designed to termed the fixed film solar concentrator (FFSC). A systematic analysis was also made on the high transmittance to photosynthetically active radiation (PAR) and effective thermal recovery of near-infrared radiation (NIR). The performance of the device was verified to selectively reflect the NIR for the thermal energy recovery, and maintain the high transmittance of the PAR. Optical simulations and physical experiments were also conducted to investigate the impact on the greenhouse microclimate and crop physiological performance. Among them, 1) in the simulation, the Python scripts were coupled with Zemax OpticStudio ray-tracing software. A full-spectrum light environment model was then established for the greenhouse. A simulation was also performed on the spectral distribution of total irradiance, PAR, and NIR in both FFSC and conventional greenhouses under typical summer- and winter-solstice solar incidence. Additionally, the NIR concentration efficiency of the FFSC device was determined for the incident angles ranging from 0-60°. The simulation platform was incorporated with the real solar position and weather models using local typical-day meteorological data. The distribution of the solar radiation in the greenhouse was accurately simulated in the temporal and spatial dimensions. The performance of the FFSC structure was reliably predicted under variable weather conditions, such as cloudy or intermittently sunny days. 2) In the experiments, the plots with the FFSC, the control plots without FFSC, and an outdoor reference were set during representative days from February to April. Radiation and temperature sensors were installed at 1.0 m above the canopy. The data was then logged automatically at 5-minute intervals. Experimental results indicated that the total daily solar radiation in the FFSC plots averaged 37.7%-39.5% of the outdoor level. The NIR fraction (21.7%-22.7%) was substantially lower than the outdoor value (greater than 40%). The selective reflection of the infrared radiation effectively reduced the indoor heat load. The average temperature increase in the FFSC plots relative to outdoors (1.8-3.3 °C) was markedly lower than that in the control plots (4.4-8.2 °C). There was an average inter-plot temperature difference of 3.6 °C (maximum 4.9 °C), with the intensifying cooling at the higher radiation levels. The photosynthetic photon flux density (PPFD) in the FFSC plots mostly remained between 700-900 μmol/(m²·s) during the high-efficiency photosynthesis period (10:00–14:00) in March and April, thus exceeding the light threshold of the crop. The results showed an average deviation of 5.2% between simulated and measured total irradiance, and PAR transmittance errors below 5% relative to theoretical values. Once the outdoor irradiance exceeded 600 W/m² (corresponding to a PPFD greater than 800 μmol/(m²·s)), the FFSC device fully met the requirements of the crop’s light environment. NIR reflection efficiency reached 64.0%-74.5% at the incident angles below 37.5°. But there was decrease by 38.0% at 60°. The NIR thermal energy recovery efficiency varied seasonally, thus recording 52.67% in the summer and 38.45% at the winter solstice, respectively. The FFSC device achieved the efficient separation of the photosynthetically essential PAR and heat-load-inducing NIR. There was the high-efficiency recovery of the NIR thermal energy and adequate PAR supply. It is applicable in regions where the solar irradiance exceeds 600 W/m². The device can enhance the greenhouse sustainability and microclimate regulation, in order to balance the thermal energy collection with the crop growth requirements for the normal physiological functions.