Consider the following: 1. Battery storage 2. Biomass generators 3. Fuel cells 4. Rooftop solar photovoltaic units How many of the above are considered “Distributed Energy Resources”

1. A. Only one
2. B. Only two
3. C. Only three
4. D. All four

Answer: D

Explanation

Distributed Energy Resources (DERs) are typically smaller, modular, grid-connected or stand-alone energy generation or storage units located at or near the point of consumption. They are designed to provide power to a local area or to the grid. 1. Battery storage: These systems store energy and can discharge it locally, qualifying as DERs. 2. Biomass generators: Small-scale generators that convert biomass into electricity at a local level are considered DERs. 3. Fuel cells: These devices convert chemical energy into electrical energy and can be deployed in a distributed manner. 4. Rooftop solar photovoltaic units: These are classic examples of DERs, generating electricity directly at the consumer’s premises. Since all four listed items fit the definition of DERs, the correct answer is ‘All four’. This topic is relevant to UPSC’s focus on renewable energy, energy security, and sustainable development.