UPPSC 2019 Prelims GS Paper-I · Question 29 of 150

Correct — C, Diu. In March 2018 the island of Diu — then part of the Union Territory of Daman and Diu — was declared the first Indian Union Territory to run entirely on solar energy. Diu had built roughly 13 MW of solar capacity: about 10 MW ground-mounted on some 50 acres of rocky, unused land, plus about 3 MW of rooftop plants on government buildings. Against a peak demand of only about 7 MW, that was enough for the island to stop importing power from Gujarat during daylight hours, and domestic electricity bills fell by roughly 10-12 per cent. The honest framing is the one Diu itself used: 100 per cent solar during the daytime — after sunset the island still draws on the grid, because the achievement was in generation, not in storage. Present-day note for a 2026 reader: since January 2020 Diu has been part of the merged Union Territory of Dadra and Nagar Haveli and Daman and Diu, so 'Daman and Diu' no longer exists as a separate UT.

• (a)Andaman-Nicobar — The Andaman and Nicobar Islands have long depended mainly on diesel generation, with solar and hybrid microgrids being added island by island. They were not the Union Territory credited with the first fully solar-powered milestone.
• (b)Chandigarh — Chandigarh has one of India's most aggressive rooftop-solar programmes and is often cited as a model solar city, but its solar generation meets only a part of a much larger city demand — it never claimed to run entirely on solar.
• (d)Puducherry — Puducherry's electricity comes largely from the central grid and conventional sources; it has solar installations but no claim to being the first fully solar-powered Union Territory.

A very small, isolated power system is the easiest place to reach '100 per cent renewable', because the arithmetic is forgiving: Diu's peak load of about 7 MW could be covered by about 13 MW of panels working in strong coastal sunshine, on land that had no competing use. Scale that logic up and the difficulty appears — matching a large, round-the-clock demand needs storage or firm backup, which is why 'daytime 100 per cent' and 'always 100 per cent' are very different claims. This is the same reason small islands and UTs, not big states, tend to be the sites of renewable-energy 'firsts'.

Approach the question by size and plausibility rather than by fame. Chandigarh and Puducherry are urban UTs with demand far too large for a solar-only supply, and the Andamans are a scattered, diesel-dependent archipelago. Diu is tiny, sunny and land-surplus — exactly the profile that makes a 100 per cent claim achievable. Anchor the fact to its date: March 2018, roughly twenty months before this December 2019 paper.

• Diu was declared the first Indian Union Territory to run 100 per cent on solar energy in March 2018.
• About 13 MW of solar capacity — roughly 10 MW ground-mounted over about 50 acres plus about 3 MW of rooftop installations — against a peak demand of about 7 MW.
• Consumer electricity bills fell by about 10-12 per cent after the switch.
• The accurate wording is 100 per cent solar during the daytime; the grid still supplies power at night.
• Diu was then part of the UT of Daman and Diu; that UT was merged with Dadra and Nagar Haveli in January 2020.

• Reading '100 per cent solar' as round-the-clock supply — the claim covers daytime generation.
• Confusing Diu with Daman, the other half of the old Union Territory.
• Assuming the best-known UTs (Delhi, Chandigarh) must have been first — the milestone belongs to the smallest load.

UPPSC is fond of 'first state / first UT to…' recall items; UPSC asks the same subject through policy — solar capacity targets, the ISA, rooftop schemes and grid integration.

• practice — not a real PYQ

  Diu, the first Indian Union Territory to run entirely on solar energy during the daytime, is today part of which Union Territory?

  • (a)Lakshadweep
  • (b)Puducherry
  • (c)Dadra and Nagar Haveli and Daman and Diu
  • (d)Andaman and Nicobar Islands

  Answer(c) Dadra and Nagar Haveli and Daman and Diu — the two Union Territories were merged into a single UT with effect from January 2020.

• practice — not a real PYQ

  When a town or island is described as running '100 per cent on solar energy', the claim normally means that

  • (a)all its electricity, day and night, comes from solar power
  • (b)its daytime demand is met by solar generation while the grid supplies power at night
  • (c)solar power is used only for street lighting and public buildings
  • (d)all its vehicles run on solar energy

  Answer(b) Its daytime demand is met by solar generation while the grid supplies at night — without large-scale storage, solar cannot cover the night, which is exactly how Diu's 2018 achievement was framed.