UPSC Prelims 2024 GS Paper I · Q47 of 96 Environment & Ecology medium

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 ✓ UPSC's answer

Why the answer is (d)

• Distributed Energy Resources (DERs) are small-scale generation or storage units located at or near the point of consumption and connected to the distribution grid, as opposed to large centralised power stations.

• Rooftop solar photovoltaic units are the most common DER (item 4); biomass generators at farms or factories are another (item 2).

• Fuel cells installed at buildings generate power locally (item 3), and battery storage at homes or substations stores and dispatches energy (item 1).

• Together with demand response and electric-vehicle chargers, these make up the DER ecosystem that smart grids manage.

• All four qualify, option (d).

Why the other options are wrong

(a) Only one
All four, not one, are DERs.
(b) Only two
Fuel cells and biomass generators are also DERs.
(c) Only three
Battery storage is also a DER, making four.

Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2024, held on 16 June 2024. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.

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