Read the passage and answer the questions that follow: For more than nine decades scientists have tried to replicate the process that produces energy for the sun and stars-fusion. On Tuesday, researchers at the National Ignition Facility (NIF) in California, USA, announced a milestone in this endeavour. They merged two nuclei to produce a heavier nucleus. Their reactor produced about 1.5 times more energy than what was used in the process. In all the earlier attempts to harness the power of fusion, the reactors used up more energy than what was produced. But scientists say that it will be at least two decades before the process pioneered in the California laboratory can be scaled up. Even then, in a world desperately searching for technologies that can power the developmental needs of nations adding to the GHG load, the break-through at NIF has generated excitement. Several countries are shifting to renewable energies to meet their international climate-related commitments. Yet, power generation currently is responsible for 25-30 percent of global GHG emissions. The inherently unstable nature of renewables means that countries find it very difficult to jettison fossil-fuel energy sources. Conventionally-produced nuclear energy-that uses fission technology-is relatively cleaner. But accidents at Chernobyl in 1986 and Fukushima in 2011 have raised serious questions over the safety of fission-powedered plants.
According to current estimates, power generation accounts for how much of the total GHG emissions on earth?
Understanding Power Generation and GHG Emissions
The question asks about the estimated percentage of total Greenhouse Gas (GHG) emissions on Earth that comes from power generation. We need to carefully read the provided passage to find this specific information.
Analyzing the Passage for GHG Emission Data
Let's read through the passage again, looking for mentions of GHG emissions and their source.
- The passage discusses fusion energy research at NIF and its potential.
- It mentions countries shifting to renewable energies to meet climate commitments.
- It then states: "Yet, power generation currently is responsible for 25-30 percent of global GHG emissions."
- The passage also contrasts renewable energy with fossil fuels and fission nuclear energy in the context of emissions and reliability.
The sentence "power generation currently is responsible for 25-30 percent of global GHG emissions" directly provides the answer to the question.
Identifying the Correct Percentage of GHG Emissions
Based on the explicit statement in the passage:
- Power generation contributes 25-30 percent of global GHG emissions.
Now let's compare this with the given options:
- Option 1: 10-15 percent
- Option 2: 25-30 percent
- Option 3: 40-45 percent
- Option 4: 50-55 percent
The percentage range stated in the passage matches Option 2.
Conclusion on Power Generation Emissions
According to the estimates provided in the passage, power generation accounts for 25-30 percent of the total GHG emissions globally. This highlights the significant role of the energy sector in contributing to climate change and the importance of shifting towards cleaner energy sources.
| Source | Estimated Contribution to Global GHG Emissions |
|---|---|
| Power Generation | 25-30 percent |
| Other sectors contributing to GHG load (implied) | The remaining percentage (70-75 percent) |
Revision Table: Key Concepts
| Concept | Explanation based on Passage |
|---|---|
| GHG Emissions | Gases contributing to the greenhouse effect and climate change. |
| Power Generation | The process of generating electrical energy, often from burning fossil fuels. |
| Contribution of Power Generation to GHG | Estimated at 25-30 percent of total global GHG emissions. |
Additional Information: Energy Sources and Emissions
The passage touches upon various energy sources and their characteristics regarding emissions and reliability.
- Fossil Fuels: Mentioned as sources countries find difficult to jettison due to the unstable nature of renewables. Burning fossil fuels (like coal, oil, and natural gas) is a primary source of GHG emissions from power generation.
- Renewable Energies: Such as solar and wind power. They are shifting to renewables to meet climate commitments. Inherently unstable nature is mentioned as a challenge. Renewables generally have very low or zero operational GHG emissions.
- Conventionally-produced Nuclear Energy (Fission): Relatively cleaner in terms of GHG emissions compared to fossil fuels. However, safety concerns from accidents (Chernobyl, Fukushima) are highlighted.
- Fusion Energy: The focus of the NIF breakthrough. The goal is to replicate the sun's process. Fusion has the potential for virtually limitless, clean energy with minimal long-lived radioactive waste, but it is still in the experimental stage.
Understanding the contribution of different sectors, especially power generation, to global GHG emissions is crucial in the context of climate action and the transition to sustainable energy systems.
Important Questions from Reading Comprehension
Why, according to the writer can't people be motivated to use a resource prudently?
1. They feel that others may overuse the resource
2. It is possible to substitute the resource
3. Abundance of the resource availability
Select the correct answer using the code given below:
When do people use resources exhaustively?
The self-interest of people affects the use of renewable resources
People rooted in a locality
Which among the following is closest in meaning with the word 'deplete'?
