Which energy challenge is associated with renewable resources?

• A. Intermittency and storage requirements.
• B. There are no storage requirements.
• C. They cannot be integrated into the grid at all.
• D. They are always cheaper with no reliability issues.

Answer: (A)

Intermittency of renewable energy generation and the need for storage and grid flexibility are central challenges. Solar and wind outputs fluctuate with time of day, weather, and seasons, so they can’t provide a perfectly constant supply. To keep the electricity system reliable, there must be ways to store excess energy for periods of low production and to balance supply and demand in real time. That leads to storage technologies (batteries, pumped hydro, thermal storage) and other flexible resources that can respond quickly when renewables dip. The other statements miss important realities: storage is not unnecessary, renewables can be integrated into the grid with proper planning, and costs and reliability vary—it's not always cheaper or free of reliability issues.