UGC NET Paper One Unit 9

People, Development and Environment - Chapter 4: Natural and Energy Resources

Natural Resources

Definition and Importance

Natural resources are materials or substances that occur in nature and can be used for economic gain or human benefit with minimal modifications. These resources are essential for various purposes including commercial and industrial use, aesthetic value, scientific interest, and cultural significance. Examples of natural resources include sunlight, atmosphere, water, land, minerals, vegetation, and wildlife.

Types and Classifications

Natural resources are an integral part of Earth's natural heritage and are often protected in nature reserves to preserve biodiversity and geodiversity. These resources can be classified in several ways:

• Renewable Resources

Resources that can be replenished naturally over time, such as sunlight, wind, and biomass.

• Non-Renewable Resources

Resources that cannot be replenished once they are depleted, such as fossil fuels (coal, oil, and natural gas), minerals, and metals.

Examples of Natural Resources

  • Freshwater: Essential for drinking, agriculture, and industry.
  • Air: Vital for all aerobic life forms.
  • Living Organisms: Fish, forests, and wildlife.
  • Extracted Resources: Metal ores, rare-earth elements, petroleum, timber, and most forms of energy.

Economic and Political Implications

The allocation and extraction of natural resources are often central to economic and political conflicts. Scarcity and overconsumption can lead to confrontations within and between countries. Resource extraction has also been linked to human rights violations and significant environmental damage.

Sustainable Management and Development

The Sustainable Development Goals (SDGs) and other international agendas emphasize the need for sustainable resource extraction. Efforts are being made to develop economic models that reduce reliance on resource extraction. These models, such as the circular economy, focus on reuse, recycling, and the sustainable management of renewable resources. The goal is to create a balance between resource use and environmental conservation, ensuring that natural resources are available for future generations.

In summary, natural resources are vital for human survival and economic development. However, their management requires careful consideration to avoid depletion and environmental degradation, ensuring sustainability for future generations.

Hydropower

Water, being about 800 times denser than air, can generate substantial amounts of energy even from a slow-flowing stream or moderate sea swell. Water can generate electricity with a conversion efficiency of about 90%, the highest rate among renewable energy sources. There are various forms of water energy:

Large Hydroelectric Dams and Reservoirs

Historically, hydroelectric power has been generated by constructing large dams and reservoirs. Examples include the Three Gorges Dam in China and the Itaipu Dam built by Brazil and Paraguay.

Small Hydro Systems

These installations typically produce up to 50 MW of power and are often used on small rivers or as low-impact developments on larger rivers. China leads the world in hydroelectricity production with more than 45,000 small hydro installations.

Run-of-the-River Hydroelectricity

These plants derive energy from rivers without creating large reservoirs. Water is conveyed along the side of the river valley using channels, pipes, or tunnels until it is high above the valley floor, then allowed to fall through a penstock to drive a turbine. These plants can still produce large amounts of electricity, such as the Chief Joseph Dam on the Columbia River in the United States. However, many run-of-the-river plants are micro or pico hydro plants.

Advantages and Challenges

Flexibility and Global Capacity

Hydropower is highly flexible and can complement wind and solar power. As of 2021, the global renewable hydropower capacity was 1,360 GW. However, only a third of the world's estimated hydroelectric potential of 14,000 TWh/year has been developed.

Challenges

New hydropower projects often face opposition from local communities due to their large impact, including the relocation of communities and flooding of wildlife habitats and farming land. High costs and long lead times due to the permission process, including environmental and risk assessments, and the lack of environmental and social acceptance, are primary challenges for new developments.

Repowering and Upgrading

It is popular to repower old dams to increase their efficiency and capacity and improve their responsiveness on the grid. For example, existing dams like the Russell Dam, built in 1985, may be updated with "pump back" facilities for pumped-storage, useful for peak loads or to support intermittent wind and solar power.

Economic and Environmental Considerations

Value of Dispatchable Power

Dispatchable power (power that can be turned on or off as needed) is more valuable than variable renewable energy (VRE) sources like wind and solar. Countries with large hydroelectric developments, such as Canada and Norway, are investing billions to expand their grids to trade with neighboring countries that have limited hydro resources.

Water energy, through various forms of hydropower, plays a crucial role in renewable energy production. While large-scale projects have been the traditional focus, small and run-of-the-river systems offer significant potential with lower environmental impacts. Addressing challenges such as community opposition, high costs, and long lead times is essential for the continued expansion and optimization of hydropower.

India's Hydroelectric Power: Current Status and Challenges

Global Standing and Capacity

India is ranked 5th globally for installed hydroelectric power capacity. As of 31 March 2020:

  • Installed Utility-Scale Hydroelectric Capacity: 46,000 MW (12.3% of total utility power generation capacity).
  • Smaller Hydroelectric Units: Total capacity of 4,683 MW (1.3% of total utility power generation capacity).
  • Total Hydroelectric Potential: Estimated at 148,700 MW at a 60% load factor.

Historical Context

The hydroelectric power plants at Darjeeling (1898) and Shivanasamudra (1902) were among the first in Asia, marking India's early involvement in global hydroelectric power development. India also imports surplus hydroelectric power from Bhutan.

Categories of Hydropower

Small Hydropower

  • Facilities with nameplate capacities up to 25 MW
  • Managed by the Ministry of New and Renewable Energy (MNRE)

Large Hydropower

  • Facilities above 25 MW
  • Managed by the Ministry of Power

Largest Hydroelectric Plant

  • Koyna Hydroelectric Project
  • With a capacity of 1,960 MW

Recent Performance and Challenges

In the fiscal year 2019–20:

  • Total Hydroelectric Power Generated: 156 TWh (excluding small hydro)
  • Average Capacity Factor: 38.71%

However, in the fiscal year ending March 31, 2024:

  • Decline in Hydroelectric Output: A 16.3% drop, the largest decline in 38 years, due to low rainfall
  • Hydroelectricity's Share of Total Power Generation: Fell to a historic low of 8.3%
  • Hydroelectric Generation: Reached a five-year low of 146 billion kWh
  • Increased Reliance on Coal: Due to the shortfall in hydroelectric power
  • Influence of Weather Patterns: Lightest rainfall since 2018, potentially influenced by the El Niño weather pattern

Implications and Future Outlook

The decline in hydroelectric power generation highlights the vulnerabilities and challenges posed by erratic weather patterns. This has led to a diminished role for hydroelectric power in India's energy mix and increased reliance on coal.

Wind Power

Definition and Basics

Wind power is the use of wind energy to generate useful work. Historically, it was utilized by sails, windmills, and windpumps. Today, wind power is primarily used to generate electricity using wind turbines, which are generally grouped into wind farms and connected to the electrical grid.

Wind Farms are large concentrations of wind generators producing electricity. Asked in Exam

Wind Farms are often installed in rows, create noise pollution, can be installed on land or offshore, and contribute electricity to the power grid. Asked in Exam

Wind energy does not have a high energy density compared to other sources of energy like fossil fuels.

Current Status and Global Leaders

In 2022, wind power supplied over 2000 TWh of electricity, accounting for over 7% of global electricity and about 2% of world energy. With approximately 100 GW added during 2021, global installed wind power capacity exceeded 800 GW. As of now, China is the leading country in wind energy-based electricity production. Asked in Exam

Advantages and Challenges

Wind power is a sustainable and renewable energy source with a much smaller environmental impact compared to burning fossil fuels. However, there are inherent challenges:

Intermittency: Wind energy is an intermittent source of energy. Asked in Exam Wind speed variability affects energy production, requiring energy storage or other dispatchable generation sources to ensure a reliable electricity supply.

Types of Wind Farms and Locations

Onshore Wind Farms

These have a greater visual impact on the landscape compared to most other power stations per unit of energy produced.

Offshore Wind Farms

These have less visual impact and higher capacity factors but are generally more expensive. Offshore wind power currently accounts for about 10% of new installations.

Location Potential

Regions in the higher northern and southern latitudes have the highest potential for wind power. Coastlines are considered as high potential areas for wind energy generation. Asked in Exam

Additionally, ocean water can be utilized as a coolant during wind energy production. Asked in Exam

Cost and Efficiency

Wind power is one of the lowest-cost electricity sources per unit of energy produced. In many locations, new onshore wind farms are cheaper than new coal or gas plants. Wind power generation is often higher at night and in winter when solar power output is low, making wind and solar power combinations suitable for many countries.

Impact on Environment and Landscape

Wind power offers a sustainable alternative to fossil fuels with significantly lower environmental impacts. However, specific environmental concerns exist for different energy sources:

Comparative Environmental Impacts of Energy Sources

Thermal Energy is associated with the emission of greenhouse gases. Asked in Exam

Hydroelectric power leads to a loss of riparian vegetation. Asked in Exam

Photovoltaic energy involves the production of toxic wastes. Asked in Exam

Wind Energy is hazardous for birds and bats. Asked in Exam

Specific Impacts of Wind Power

1. Wildlife Concerns

  • Habitat loss & fragmentation affect ecosystems.
  • Bird & bat mortality from turbine collisions. Wind Energy is hazardous for birds and bats. Asked in Exam
  • However, statistics show fewer bird deaths than fossil fuel plants.

2. Visual & Land Use Impact

  • Wind farms have a significant visual presence.
  • Large land area needed due to turbine spacing.
  • Energy sprawl allows agriculture between turbines.
  • May impact tourism in scenic landscapes.

3. Turbine Blade Disposal

  • Fiberglass blades last ~20 years before disposal.
  • Recycling efforts include repurposing for bridges.
  • New blades designed for full recyclability.

4. Noise & Health Impact

  • Noise levels at 300m are ~45 dB, similar to a fridge.
  • No scientific evidence linking turbines to health issues.

Key Concepts and Terms

Wind Turbine

Converts wind kinetic energy into mechanical power.

Windmill

Uses sails on a rotating shaft to tap wind energy.

Offshore Wind Power

Generates electricity from wind farms in water. Higher wind speeds at sea increase power output.

Intermittency

Wind speed variability affects energy production.

Conclusion

Wind power plays a crucial role in the transition to renewable energy, offering a sustainable alternative to fossil fuels. Despite challenges such as intermittency and higher costs for offshore installations, wind power remains a cost-effective and environmentally friendly energy source.

Wind Energy in India: Overview and Key Facts

Importance of Wind Energy

Wind energy is a crucial renewable energy source in India, contributing significantly to the country's energy mix. India is home to some of the largest operational onshore wind farms, playing a vital role in meeting the country's renewable energy goals.

Largest Wind Power Plants in India

Wind Power Plant Megawatt (MW) Location
Muppandal wind farm 1500 Tamil Nadu, Kanyakumari
Jaisalmer Wind Park 1064 Rajasthan, Jaisalmer
Brahmanvel wind farm 528 Maharashtra, Dhule
Dhalgaon wind farm 278 Maharashtra, Sangli
Vankusawade Wind Park 259 Maharashtra, Satara District
Vaspet 144 Maharashtra, Vaspet
Tuljapur 126 Maharashtra, Osmanabad
Beluguppa Wind Park 100.8 Andhra Pradesh, Beluguppa
Mamatkheda Wind Park 100.5 Madhya Pradesh, Mamatkheda
Anantapur Wind Park 100 Andhra Pradesh, Nimbagallu

Key Wind Power Plants in India

Muppandal Wind Farm: Developed by Tamil Nadu Energy Development Agency, it is the largest operational onshore wind farm in India.

Jaisalmer Wind Park: Located in Rajasthan, developed by Suzlon Energy, it is the second-largest operational onshore wind farm in India.

Vankusawade Wind Park: Located in Maharashtra's Satara District, it is a significant wind farm on a high mountain plateau.

Wind Power Potential and Policies in India

Potential

India has an estimated wind power potential of 148,700 MW. Western states like Gujarat, Maharashtra, Karnataka, Tamil Nadu, and Andhra Pradesh have stable and strong wind flow, making them ideal for wind energy projects.

Top States for Installed Capacity

  • Tamil Nadu: Largest installed wind power capacity, contributing 28% to its electricity generation in 2018.
  • Gujarat: Second-largest installed capacity, contributing 19%.
  • Maharashtra, Karnataka, and Rajasthan: Follow in terms of installed wind power capacity.

Policies

National Wind Power Policy: Framework for developing wind energy.

National Offshore Wind Energy Policy: Launched in October 2015 to develop offshore wind energy.

Solar-Wind Hybrid Policy: Issued in May 2018 to promote large grid-connected wind-solar hybrid systems for optimal resource utilization and grid stability.

Global Context

India's Muppandal wind farm and Jaisalmer Wind Park are among the top 10 largest wind power plants in the world.

Wind Power Plant Megawatt (MW) Location
Gansu 7,965 China
Alta 1,548 United States of America (USA)
Muppandal wind farm 1,500 Tamil Nadu, Kanyakumari
Jaisalmer Wind Park 1,064 Rajasthan, Jaisalmer
Los Vientos Wind Farm 912 United States of America (USA)
Shepherds Flat 845 United States of America (USA)
Meadow Lake Wind Farm 801 United States of America (USA)
Roscoe 782 United States of America (USA)
Horse Hollow 736 United States of America (USA)
Tehachapi Pass Wind Farm 705 United States of America (USA)

Wind energy is a vital part of India's renewable energy strategy. With substantial potential and supportive policies, India aims to expand its wind energy capacity, contributing to global efforts in combating climate change and promoting sustainable development.