The challenges for optimum use of renewable sources of energy include:
1. High waste disposal costs
2. Unreliable supply
3. High running costs
4. High per unit cost of energy
Select the correct option from the codes given below:

Answer: [C] Only 2 & 4

The advantages of the renewable sources of water include Wide availability, Lower running cost, Decentralized power production and Low pollution. The disadvantages of include unreliable supply, production in small quantities, difficulty in storing, high per unit cost of energy currently.

This question is a part of GKToday's Integrated IAS General Studies Module