The present paper aims at the material design for wind turbine blade that can sustain different environmental conditions. It is difficult to keep regular maintenance of blade; we need to design a material that can repair the damage by its own. The present work is an attempt to study the effect of moisture, temperature and saline medium on glass fiber-reinforced polymer (GFRP) having Cloisite 30B (nanoclay) as reinforcement in epoxy polymer matrix. The changes in the physical and mechanical properties of the composite material under accelerated condition have been studied. The concept of self-healing is a vital tool to encounter the damage by itself. We have used DCPD (dicyclopentadiene)-contained microcapsules as a healing agent. These microcapsules have shown a great decrease in the rate of degradation of blade material. Wind turbine blades are mainly made up of FRP composites, and these composites have tendency to absorb moisture. It has been observed that water absorption can affect the mechanical performance as well as reduce the durability of turbine blade. To encounter this effect, nanoclay as filler has been used in GFRP composites. It has been noticed that degradation reduces to high extent. The percentage reduction in strength is more in saline water than in normal tap water. Epoxy samples show more degradation in saline medium (39-46\%) at 40 degrees C as compared to plain water medium (29-41\%) at the same temperature.