When overcast. When low solar radiation. When hail/disaster damaged ( highly vulnerable technology) Approx. 20-25yr (max.) life.
The above are max c. 25% efficient.
Lack of wind. Too much wind. Blown nacelles. Approx.20-25 yr (max.) life.
The above are max c. 25% efficient.
Both have an Increasing probability of failure without subsidies.
High probability of redundancy when business cannot afford to make products and services that consumers are willing to pay prices above their propensity to purchase. The redundancy point is not a reported fact but a consideration of potential outcome according to current Wind/Solar strategies.
