UPSC Essentials | Mains answer practice — GS 3 : Questions on spacecraft splashdown and renewable energy (Week 114)

QUESTION 1

Discuss why rapid expansion of renewable energy capacity has not translated into substantial reductions in fossil fuel use and greenhouse gas emissions at the global level.

QUESTION 2

Discuss the merits and demerits of splashdown (water landings) versus runway (ground) landings for crewed spacecraft with reference to recent missions such as Axiom‑4.

General points on the structure of the answers

Introduction

— The introduction of the answer is essential and should be restricted to 3-5 lines. Remember, a one-liner is not a standard introduction.

— It may consist of basic information by giving some definitions from the trusted source and authentic facts.

Body

— It is the central part of the answer and one should understand the demand of the question to provide rich content.

— The answer must be preferably written as a mix of points and short paragraphs rather than using long paragraphs or just points.

— Using facts from authentic government sources makes your answer more comprehensive. Analysis is important based on the demand of the question, but do not over analyse.

QUESTION 1: Discuss why rapid expansion of renewable energy capacity has not translated into substantial reductions in fossil fuel use and greenhouse gas emissions at the global level.

Note: This is not a model answer. It only provides you with thought process which you may incorporate into the answers.

Introduction:

— The world added about 582 gigawatts (GW) of renewable energy capacity in 2024, representing an increase of 15% over the previous year, according to a new report by the International Renewable Energy Association (IRENA). This was the largest annual increase in renewable energy capacity in any single year.

— Currently, the installed capacity of renewable energy worldwide exceeds 4,442 GW, and renewable sources generate almost 30% of the world’s electricity.

— According to a new IRENA report, with the present rate of expansion, the world will be close to meeting its 2030 aim of tripling renewable energy installed capacity. This aim is deemed critical for controlling global warming and was included in the accord reached at the COP28 summit in Dubai in 2023.

Body:

You may incorporate some of the following points in your answer:

— The rapid expansion of renewable energy may give the impression that the world has made significant progress towards fulfilling its climate goals. However, renewable energy has yet to displace fossil fuels on a global scale.

— While fossil fuels accounted for only around 10% of new power installed capacity in 2024, their use is still increasing, according to the IRENA report.

— Between 2012 and 2023, global power generation increased by 2.5% per year on average, while renewable energy expanded at a rate of approximately 6%. This has resulted in a continuous increase in the proportion of renewables in the power generation mix. However, fossil fuels today generate more than 70% of worldwide electrical generation.

— In absolute terms, more fossil fuels are consumed today than ten years ago to generate power. To make matters worse, the growth in the consumption of fossil fuels is projected to last for at least a few years. As a result, greenhouse gas emissions have reached historic levels in recent years.

— In some nations, particularly in the Nordic region, renewables make for a substantially larger share of overall energy use. However, the unique conditions found in these countries are difficult to recreate elsewhere. According to forecasts, by 2050, renewable energy will account for no more than 40% to 45% of total global energy consumption.

Conclusion:

— The IRENA report pointed out that while renewable capacity increased by 15% globally in 2024, in Africa it grew by just 7%, and that too from a very low base. Africa is where the largest number of people without access live.

— China’s management of the renewable energy system has begun to resemble the OPEC countries’ influence over global oil supplies. Energy security has emerged as one of the most pressing problems for governments, prompting many of them to secure whatever option is available to them, clean or not.

— The move to clean and renewable energy systems is not as simple as some claim. There are multiple levels of complexity that make the objective of reducing global temperatures to below 2 degrees Celsius appear more unattainable.

(Source: Why increasing renewable energy alone can’t solve climate crisis)

Points to Ponder

Read more about renewable energy and its sources

Why do Nordic countries produce more green electricity?

Related Previous Year Questions

The adoption of electric vehicles is rapidly growing worldwide. How do electric vehicles contribute to reducing carbon emissions and what are the key benefits they offer compared to traditional combustion engine vehicles? (2023)

Industrial pollution of river water is a significant environmental issue in India. Discuss the various mitigation measures to deal with this problem and also the government’s initiatives in this regard. (2024)

QUESTION 2: Discuss the merits and demerits of splashdown (water landings) versus runway (ground) landings for crewed spacecraft with reference to recent missions such as Axiom‑4.

Note: This is not a model answer. It only provides you with thought process which you may incorporate into the answers.

Introduction:

— Landing in the ocean is the preferred method of returning humans from space, while some spacecraft do land on a runway, just like an aeroplane. However, the latter has unique requirements, necessitates more advanced technology, and is typically more expensive.

— The spacecraft carrying Indian astronaut Shubhanshu Shukla and his three Axiom-4 mission colleagues splashed down in the Pacific Ocean following a 20-hour voyage from the International Space Station.

Body:

You may incorporate some of the following points in your answer:

— Splashdown is often a simpler and safer alternative. When a spacecraft begins to re-enter the Earth’s atmosphere at an altitude of 110-120 km, it typically travels at speeds of up to 27,359 km/h. There isn’t enough time for it to slow down to speeds appropriate for a vertical landing on the ground. Additional braking devices and structures, such as landing legs, will be necessary.

— It is safer to land a spacecraft in water, even if it is moving at 25-30 km/h – the speed of the Axiom-4 spacecraft at splashdown. Water’s low viscosity and high density provide a far bigger cushion. While it does not guarantee a perfect landing, it absorbs enough shock from the impact to prevent damage to the spacecraft’s construction, payload, or crew.

— The other cause is the abundance of large open spaces. On the ground, the landing point must be exactly defined; in the ocean, even if the spacecraft is carried slightly off course by air or sea currents, there is no risk of colliding with anything else.

— The capsules are designed to float in water. They are conical in shape, with rounded metal on either the top or bottom (depending on how they fall), similar to a ship’s hull, that keeps them bobbing on the surface.

Conclusion:

How is landing done?

— When a spacecraft re-enters the Earth’s atmosphere, it decelerates owing to friction. However, extra precautions are required to slow it to a safe speed. One such method is to employ parachutes. Spacecraft often deploy two drag (or drogue) parachutes first, which stabilise the vehicle during re-entry and lower speed. These parachutes are deployed by the Dragon spacecraft at an altitude of around 18,000.

— At approximately 6,500 feet, the drogue parachutes are removed, and the four main parachutes are released, further slowing the ship.

— The spaceship does not fly vertically to Earth, but rather descends at an angle. From re-entry to touchdown, it travels 5,000-7,000 kilometres. During this period, its speed drops to around 25-30 km/h, which is safe for a splashdown in the ocean.

(Source: Why spacecraft prefer splashdowns over landing on ground)

Points to Ponder

Read more about Axiom-4 mission

Read about proposed Gaganyaan mission

Related Previous Year Questions

What is the main task of India’s third moon mission which could not be achieved in its earlier mission? List the countries that have achieved this task. Introduce the subsystems in the spacecraft launched and explain the role of the Virtual Launch Control Centre’ at the Vikram Sarabhai Space Centre which contributed to the successful launch from Sriharikota. (2023)

India has achieved remarkable successes in unmanned space missions including the Chandrayaan and Mars Orbiter Mission, but has not ventured into manned space mission. What are the main obstacles to launching a manned space mission, both in terms of technology and logistics? Examine critically. (2017)

Previous Mains Answer Practice

UPSC Essentials: Mains answer practice — GS 3 (Week 112)

UPSC Essentials: Mains answer practice — GS 3 (Week 113)

UPSC Essentials: Mains answer practice — GS 2 (Week 112)

UPSC Essentials: Mains answer practice — GS 2 (Week 113)

UPSC Essentials: Mains answer practice — GS 1 (Week 112)

UPSC Essentials: Mains answer practice — GS 1 (Week 113)

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