Total light transmittance of glass fiber-reinforced polymer laminates for multifunctional load-bearing structures

The total light transmittance of hand lay-up glass fiber-reinforced polymer laminates for building construction was investigated with a view to two architectural applications: translucent load-bearing structures and the encapsulation of photovoltaic cells into glass fiber-reinforced polymer building skins of sandwich structures. Spectrophotometric experiments on unidirectional and cross-ply glass fiber-reinforced polymer specimens in the range from 0.20 to 0.45 fiber volume fraction and artificial sunlight exposure experiments on encapsulated amorphous silicon photovoltaic cells were performed. Analytical models have been developed to predict light transmittance through glass fiber-reinforced polymer structures and the percentage of solar radiation reaching encapsulated photovoltaic cells. The total amount of fibers in the laminates was the major parameter influencing light transmittance, with fiber architecture having little effect and regardless of fiber volume fraction. Eight-three percent of solar irradiance in the band of 300-800nm reached the surface of amorphous silicon photovoltaic cells encapsulated below structural glass fiber-reinforced polymer laminates with a fiber reinforcement weight of 820g/m(2), demonstrating the feasibility of conceiving multifunctional glass fiber-reinforced polymer structures.