• • Optimal transmittance varies by city: Xi'an 30%, Lanzhou 40%, Yinchuan 50%, Xining 55%, Urumqi 60%. This directly determines the balance between daylighting, heating, and power generation, with higher transmittance favoring high heating-load regions.
• • Energy-saving rates relative to a conventional reference room are 18.4% (Xi'an), 21.9% (Lanzhou), 22.7% (Yinchuan), 21.4% (Xining), and 16.9% (Urumqi). These values represent the net effect of reduced heating and lighting loads minus increased cooling loads, demonstrating the technology's viability in cold, sunny climates.
• • The photovoltaic generation can fully offset interior lighting energy consumption in resource-rich areas, as evidenced by the compensation effect observed in the simulations. This reduces net grid demand and enhances overall building energy autonomy.
• • In regions with higher heating loads, selecting higher-transmittance components is more beneficial for energy savings, as the additional solar gains reduce heating demand despite potential cooling penalties. This provides a design rule for cold climates with long heating seasons.