What are the advantages and challenges of wind energy?

Advantages: no fuel cost, zero emissions during operation, mature technology with declining costs, scalable (small to multi-MW), land can be used simultaneously for farming (onshore), and excellent offshore resources. Challenges: intermittency (variable wind speeds), visual and noise impact, bird and bat mortality, need for grid infrastructure in remote windy areas, and variability requiring backup or storage. The wind industry continues to grow with larger, more efficient turbines and improved forecasting for grid integration.