Energy Conservation, Management and Planning: NBSE Class 11

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Get notes, summary, questions and answers, MCQs, extras, and PDFs of Chapter 21 “Energy Conservation, Management and Planning” which is part of NBSE Class 11 Environment Education. However, the notes should only be treated as references and changes should be made according to the needs of the students.

Summary

Chapter 21 covers energy conservation, management, and planning. Energy is essential for modern life, but we are running out of resources. Therefore, it is important to conserve energy by using it efficiently. Energy conservation involves using less energy without compromising productivity and comfort. Some key ways to achieve this include upgrading technology, improving operation and maintenance, and providing incentives for energy-saving practices.

In households, energy can be saved through simple habits, like using pressure cookers for cooking, turning off stoves before cooking is done, using public transport, and replacing bulbs with energy-efficient CFLs or LEDs. Industry, being the largest energy consumer in India, can contribute significantly by adopting efficient processes and energy-saving equipment. Similarly, the agricultural sector can save energy by using more efficient irrigation pumps.

The transport sector, another major consumer of energy, can benefit from promoting bicycles and improving public transport systems. Energy-efficient vehicles, better road conditions, and proper vehicle maintenance can further reduce energy use and pollution.

In the power sector, the concept of demand-side management is gaining importance. This approach encourages power companies to help reduce customer demand for energy, rather than just focusing on increasing supply. Rational pricing of energy also encourages careful use.

Alternative fuels like ethanol, methanol, hydrogen, and fuel cells offer potential solutions to reduce dependence on conventional fuels. These alternatives are environmentally friendly and efficient, but further development is needed for widespread use. Lastly, nanotechnology holds promise for improving the efficiency of energy devices and utilisation, making significant contributions to global energy savings and reducing emissions.

Textbook solutions

Multiple-Choice Questions

1. Which of the following is not a way to save electricity?

A. Use of CFLs & LEDs
B. Using batteries rather than mains
C. Minimising use of natural light
D. Defrosting the refrigerator regularly

Answer: B. Using batteries rather than mains

2. In India, which sector is the largest consumer of energy?

A. Industry
B. Agriculture
C. Transport
D. Power

Answer: A. Industry

3. Which part of agriculture consumes the maximum amount of energy?

A. Sowing of seeds
B. Tractor
C. Harvesting
D. Irrigation using water pumps

Answer: D. Irrigation using water pumps

4. Conservation of energy means

A. Using energy unrestricted
B. Not using energy at all
C. Using energy judiciously
D. All of these

Answer: C. Using energy judiciously

5. Device used in New Zealand to reduce hot water costs by two-thirds in a shed is

A. Octane rating
B. Electrolyte
C. Mahana Blue
D. Fuel cells

Answer: C. Mahana Blue

Short Answer Questions

1. What do you mean by conservation of energy?

Answer: Conservation of energy refers to the judicious use of energy resources. It involves avoiding wastage of energy and adopting methods to conserve energy without affecting productivity and comforts.

2. What is cogeneration?

Answer: Cogeneration means production of two useful forms of energy such as high temperature heat or steam and electricity from the same fuel source.

3. What is demand side management?

Answer: Demand side management strategies aim to influence or reduce the demand for a product or service by pricing, incentives, and other policies.

4. What is an energy audit?

Answer: Energy audit is an official scientific study of energy consumption at any level (regional, organisational or plant level) with the aim of reduction in energy costs and consumption without affecting the productivity and comforts, and suggesting methods for energy conservation and reduction in energy costs.

5. What is energy planning?

Answer: Energy planning is a process in which data regarding demand, shortfall, production, imports, etc., are collected for the past years, the trends are analysed, and based on this, the demand for future is predicted. It is part of the energy strategy to ensure uninterrupted energy supply to consumers on both short-term and long-term bases.

6. What is a fuel cell?

Answer: Fuel cells are power-generating devices that electrochemically convert the chemical energy of a fuel to electricity. As there is no combustion involved, the efficiency of fuel cells is very high.

7. What is nanotechnology?

Answer: Nanotechnology is a technology that involves the study and manipulation of matter on a nanometre (1–100 billionth of a metre) scale.

8. Why is water-free alcohol required?

Answer: Water-free alcohol is required because water and alcohol combined cannot dissolve in gasoline, and all traces of water must be removed for fuel ethanol to work as an effective alternative among fuel sources.

9. Why is hydrogen considered unsafe as an ordinary fuel?

Answer: Hydrogen is considered unsafe as an ordinary fuel due to its explosive nature.

Long Answer Questions

1. How can we promote energy conservation?

Answer: The ways in which we can promote energy conservation are as below:

• Using, producing, managing and distributing energy more efficiently.
• Improving efficiency by technological upgradation and improved operation and maintenance.
• Providing incentives for energy-saving equipment, practices and techniques.
• Pricing energy in a realistic way.

2. What are the steps you can take in your household to save energy?

Answer: We can save energy by adopting the following steps:

• We should reduce wasteful consumption by not buying unnecessary things.
• We can also save energy by using energy-efficient equipment. It requires investment in either new equipment or in proper maintenance of older equipment.
• Energy-efficient models may cost more initially than the conventional models, but they save money in the long run.
• Energy conservation is the cheapest and the largest source of energy available to us.

3. What changes in transport system can help to save energy?

Answer: The changes in the transport system that can help save energy are:

• Use public transport whenever possible.
• Walk or cycle for short distances.
• Get your vehicle serviced regularly to keep it in good condition and to keep petrol consumption down.
• Using improved aerodynamics to minimise drag can increase vehicle fuel efficiency.
• Reducing vehicle weight can also improve fuel economy. This is why composite materials are widely used in car bodies.
• More advanced tyres, with decreased road friction and rolling resistance, can save fuel.
• Fuel economy can be improved by up to 3.3% by keeping tyres inflated to the correct pressure.

4. What are the benefits of energy conservation?

Answer: The benefits of energy conservation are as follows:

• Saves money and helps in saving fossil fuels.
• Reduces dependence on imported energy resources.
• It is the least-cost option for increasing energy supply.

5. Explain the construction of a fuel cell with the help of a diagram.

Answer: Fuel cells are power-generating devices that electrochemically convert the chemical energy of a fuel to electricity. As there is no combustion involved, as in the case of heat engines, the efficiency of fuel cells is very high. The basic construction of a fuel cell consists of two electrodes, which are separated by an electrolyte. Hydrogen is fed to the anode while oxygen is fed to the cathode. They ultimately react and form electricity and water.

H₂ anode → Hydrogen H₂ electrolyte → O₂ cathode (Air)

Overall reaction: H₂ + ½O₂ → H₂O + electricity

6. What are the advantages of a fuel cell?

Answer: The advantages of a fuel cell are as follows:

• They have low emissions as compared to conventional vehicles.
• Fuel cells are modular and can be given different shapes to fit available space.
• In fuel-cell vehicles, since chemical energy is directly converted to electricity, no energy is lost to heat.
• It is two to three times more efficient than an internal combustion engine in converting fuel to power.

7. What are the advantages of ethanol as a fuel?

Answer: The advantages of ethanol as a fuel are:

• It reduces air pollution.
• It reduces dependence on imported fuels.
• It is applicable for both light and heavy vehicles.
• Maintenance assistance required is more or less identical to that of conventional fuels.

8. Write the ways to enhance a vehicle’s energy efficiency.

Answer: The ways to enhance a vehicle’s energy efficiency are:

• Using improved aerodynamics to minimise drag.
• Reducing vehicle weight by using composite materials in car bodies.
• Using more advanced tyres with decreased road friction and rolling resistance.
• Keeping tyres inflated to the correct pressure to improve fuel economy by up to 3.3%.
• Improving vehicle maintenance to ensure fuel efficiency.
• Installing fuel-injected, computer-controlled engines to reduce energy wastage.
• Using energy-efficient vehicles like bicycles.

9. Explain the energy efficiency in: (i) production, (ii) transportation, (iii) utilisation.

Answer: (i) In Production: Energy efficiency means not only efficiency in the consumption of energy but also efficiency in its generation and distribution. In thermal power plants and factories, cogeneration can be used. Cogeneration means the production of two useful forms of energy from the same source.

(ii) In Transportation: The technical experts of energy sources work on how to minimise the transport or transmission losses. Some of the points considered are:

• Location of the energy-generating plant.
• Network configuration of the generating plant.
• The types of transformers and their capacity.
• Length of the electric lines. A lesser length would lessen the loss.
• The material design and type of cable.
• The current in the line. More current would double the loss.

(iii) In Utilisation: The growing population and urbanisation have created huge demand for energy in India. Energy efficiency is the goal to reduce the amount of energy we use in our daily life. Some of these ways are:

• Installing LED lights.
• Reducing the use of heaters or coolers by insulating the home.
• Using energy-efficient vehicles like bicycles.
• Turning off lights in unoccupied rooms.
• Switching off the TV at night.
• Installing low-consuming electrical equipment at home.

Think and Answer

1. Prerna thinks it below her dignity to travel in public transport. She goes to her office in a car though there is an efficient public transport system in her area. What would you suggest to her?

Answer: I would suggest that Prerna reconsider her view on using public transport. Public transport is an excellent way to conserve energy and reduce environmental pollution. By using a car, she contributes to air pollution, traffic congestion, and unnecessary fuel consumption. Public transport is more energy-efficient, cost-effective, and helps in reducing the overall carbon footprint. It also lessens the burden on non-renewable energy sources like petrol and diesel. Moreover, using public transport reflects social responsibility and environmental awareness, values that transcend personal status or dignity.

2. Sachin is quite rich. He thinks conservation of energy should be practised by poor people only. What do you think?

Answer: Sachin’s view is incorrect. Conservation of energy is a global responsibility that should be practised by everyone, regardless of their financial status. The rich, who generally consume more energy through their lifestyles, should be more mindful of conserving it. Energy conservation helps in reducing the pressure on finite resources like fossil fuels, decreases pollution, and helps to combat climate change. Practising energy conservation is about ensuring a sustainable future for everyone, and the rich, by setting an example, can play a significant role in promoting sustainable practices. Everyone, rich or poor, benefits from a healthier, more sustainable environment.

Extras MCQs

1. What is the largest consumer of electricity in India?

A. Industry
B. Agriculture
C. Transport
D. Residential sector

Answer: A. Industry

Q. What percentage of fuel and time can a pressure cooker save during cooking?

A. 50%
B. 60%
C. 75%
D. 90%

Answer: C. 75%

Q. In India, which sector is the largest consumer of energy after industry?

A. Agriculture
B. Transport
C. Residential
D. Commercial

Answer: B. Transport

Q. Which act was passed in India to address energy conservation?

A. Energy Conservation Act 1998
B. Energy Conservation Act 2000
C. Energy Conservation Act 2001
D. Energy Conservation Act 2003

Answer: C. Energy Conservation Act 2001

Q. What can be improved to enhance vehicle fuel efficiency?

A. Vehicle weight
B. Tyre inflation
C. Aerodynamics
D. All of the above

Answer: D. All of the above

Q. What is the main consumer of energy in the agricultural sector in India?

A. Tractors
B. Water pumps
C. Harvesting machines
D. Storage facilities

Answer: B. Water pumps

Q. Which concept is crucial in the power sector for managing shortages in India?

A. Supply side management
B. Demand side management
C. Distribution management
D. Generation management

Answer: B. Demand side management

Q. What should be done to promote the use of bicycles in India?

A. Provide free bicycles
B. Improve road conditions
C. Lower bus fares
D. Increase fuel prices

Answer: B. Improve road conditions

Q. Which type of pricing policy is suggested to encourage energy conservation in India?

A. Subsidized
B. Flat rate
C. Rational
D. Tiered

Answer: C. Rational

Q. What is the estimated loss of electric energy during transmission and distribution in India?

A. 6-8%
B. 10-15%
C. 20-25%
D. More than 30%

Answer: D. More than 30%

Q. What is the primary component used in efficient chulhas to improve heat retention?

A. Electric heating
B. Chimney
C. Metal lid
D. Insulated fuelwood box

Answer: B. Chimney

Q. Which fuel is a clear, colorless liquid used as an alternative fuel and produced by fermentation?

A. Methanol
B. Hydrogen
C. Ethanol
D. Diesel

Answer: C. Ethanol

Q. Which fuel is produced from natural gas and can also be derived from wood and agricultural wastes?

A. Ethanol
B. Hydrogen
C. Methanol
D. Biodiesel

Answer: C. Methanol

14. What method is suggested to improve the efficiency of energy utilization in homes?

A. Use of incandescent bulbs
B. Installation of LED lights
C. Keeping heaters on all day
D. Increasing the use of coolers

Answer: B. Installation of LED lights

Extra Questions and Answers

1. What is energy conservation?

Answer: Energy conservation refers to the judicious use of energy resources. It involves avoiding wastage of energy and adopting methods to conserve energy without affecting productivity and comfort. It means using less energy, more wisely than before.

Q. What are some ways to promote energy conservation?

Answer: Energy conservation can be promoted through:

• Using, producing, managing, and distributing energy more efficiently.
• Technological upgrades and improved operations.
• Providing incentives for energy-saving equipment, practices, and techniques.
• Pricing energy realistically.

Q. How can energy conservation be achieved?

Answer: Energy conservation can be achieved at various stages like:

• Generation
• Transmission
• Distribution
• Utilisation Energy can be saved by changing energy-wasting habits, altering lifestyles, and using efficient technology.

Q. What are some tips to save energy while cooking?

Answer: Tips for saving energy while cooking include:

• Using a pressure cooker, which saves up to 75% of fuel and time.
• Covering vessels with a lid to keep the heat in.
• Using flat, wide-bottomed vessels for faster cooking.
• Turning off the stove a few minutes before finishing cooking to save fuel.
• Using a solar cooker to spend less on cooking fuel.

Q. How can we save energy in transport?

Answer: Energy-saving tips in transport include:

• Using public transport whenever possible.
• Walking or cycling for short distances.
• Regularly servicing vehicles to maintain fuel efficiency.
• Promoting the use of energy-efficient vehicles and developing better public transportation to reduce the use of private vehicles.

Q. What are some tips to save electricity?

Answer: Tips for saving electricity include:

• Using CFLs or LEDs rather than bulbs.
• Switching off fans and lights when leaving a room.
• Using mains power instead of batteries.
• Maximising the use of natural light.
• Not opening the refrigerator too often and defrosting it regularly.
• Installing a solar water heater.

Q. How can we save energy by changing our consumption habits?

Answer: Energy can be saved by:

• Reducing wasteful consumption by not buying unnecessary items.
• Using energy-efficient equipment, which may require investing in new equipment or maintaining older equipment properly.
• Using energy-efficient models, which may cost more initially but save money in the long run.

Q. How can the industry contribute to energy conservation?

Answer: Industry is the largest consumer of electricity in India and can contribute to energy conservation by:

• Using energy-saving equipment.
• Adopting more efficient processes and practices.
• Redesigning products to use less material or substitute new materials that require less energy to manufacture.
• Focusing on the entire life cycle of products.
• The Energy Conservation Act of 2001 supports energy conservation at various levels.

Q. Why should bicycle transport be promoted in India?

Answer: Bicycles should be promoted because:

• They do not consume fuel and are non-polluting.
• They take up less road space and require less expensive infrastructure than cars and scooters.
• Bicycles help reduce energy consumption, air, and noise pollution, and address the commuting needs of the poor. Improving road conditions for cyclists can also make cycling safer and more efficient.

Q. How can vehicle energy efficiency be enhanced?

Answer: Vehicle energy efficiency can be improved by:

• Using improved aerodynamics to reduce drag.
• Reducing vehicle weight by using composite materials.
• Using advanced tyres that decrease road friction and rolling resistance.
• Keeping tyres inflated to the correct pressure.
• Maintaining fuel-injected computer-controlled engines. These measures can significantly improve fuel efficiency and reduce energy consumption.

Q. How can land use planning contribute to energy conservation?

Answer: Land use planning and zoning can help by bringing homes closer to workplaces. This reduces the energy consumed in commuting and contributes to overall energy conservation efforts. Additionally, exploring less energy-intensive alternatives for transporting materials, like using pipelines for oil, gas, coal, and certain minerals, can also save energy.

Q. What is the main consumer of energy in the agricultural sector in India?

Answer: The main consumers of energy in the agricultural sector in India are the water pumps used for irrigation.

Q. How can energy be saved in the agricultural sector?

Answer: Energy can be saved in the agricultural sector by improving the efficiency of water pumps, which will result in significant energy savings. Additionally, savings can be achieved through motor systems, site transportation, lighting energy, reduced tillage, precision farming systems, and efficient irrigation equipment.

Q. What are the three potential areas for energy savings in agriculture?

Answer: The three potential areas for energy savings in agriculture are:

• Motor systems (especially irrigation pumping)
• On-site transportation
• Lighting energy
  These savings can amount to 10% of total energy expenses for the agricultural sector.

Q. How can dairies, nurseries, and crop farmers save energy?

Answer: Dairies, livestock producers, nurseries, crop farmers, and food processors can save energy by installing more efficient lighting, heating, and cooling systems.

Q. What is the concept of Demand Side Management (DSM) in the power sector?

Answer: The concept of Demand Side Management (DSM) in the power sector focuses on helping customers reduce their demand for power rather than attempting to meet current shortages and increasing demand. This approach is considered useful in India, which faces acute power supply shortages. A detailed action plan on DSM is being prepared to reduce power costs and make power more affordable for consumers.

Q. What is the main aim of Demand Side Management (DSM) in India’s power sector?

Answer: The main aim of DSM in India’s power sector is to reduce the cost of power delivered to consumers, making it more affordable. This is achieved by reducing demand rather than increasing supply to meet shortages.

Q. What is the issue with energy pricing policy in India?

Answer: The energy pricing policy in India is not rational because it costs much more to produce and supply energy (such as electricity, kerosene, and LPG) than what consumers pay for it. A more realistic pricing policy, combined with incentives for efficient use and penalties for wasteful use, would encourage more careful consumption of energy.

Q. What does energy efficiency mean in production?

Answer: Energy efficiency in production refers to improving efficiency not only in energy consumption but also in its generation and distribution. Cogeneration, the production of two useful forms of energy from the same source, can be used in thermal power plants and factories. For instance, waste heat from coal-fired and industrial boilers can be used to generate electricity.

Q. What is cogeneration?

Answer: Cogeneration is the production of two useful forms of energy from the same source. In India, it can be applied by using waste heat from coal-fired and industrial boilers to generate electricity, as well as by utilizing agro-industrial wastes such as bagasse for electricity generation.

Q. What factors help reduce transport or transmission losses in energy?

Answer: Factors that help reduce transport or transmission losses in energy include:

• Location of the energy-generating plant
• Network configuration of the generating plant
• Types and capacity of transformers
• Length of electric lines (shorter lines result in lesser losses)
• Material design and type of cable used
• Current in the line (higher current increases losses)

Q. What is the loss percentage in transmission and distribution of electric energy in India?

Answer: The transmission and distribution of electric energy typically include 6% to 8% losses. However, in India, the loss is significantly higher, amounting to more than 30%.

Q. How can energy efficiency be achieved in daily life?

Answer: Energy efficiency can be achieved in daily life through several practices:

• Installing LED lights
• Reducing the use of heaters or coolers by insulating homes
• Using energy-efficient vehicles like bicycles
• Turning off lights in unoccupied rooms
• Switching off appliances like the TV at night
• Installing low-consuming electrical equipment at home

Q. What does energy management involve?

Answer: Energy management involves planning, designing, directing, and controlling the supply and demand of energy. It aims to maximize productivity, minimize energy costs, and reduce pollution through the judicious use of energy. It also involves energy policy, audits, conservation measures, training, and awareness programs.

Q. What are the essential tools of energy management?

Answer: The essential tools of energy management include:

• Energy audits, which are scientific studies of energy consumption aimed at reducing costs without affecting productivity or comfort.
• Energy conservation policies, which provide guidelines and suggestions for reducing energy consumption.

Q. What is an energy audit?

Answer: An energy audit is an official scientific study of energy consumption at any level (regional, organizational, or plant level) with the goal of reducing energy costs and consumption without affecting productivity and comfort. It involves analyzing energy data, consulting workers, and recommending conservation methods.

Q. What does energy planning involve?

Answer: Energy planning involves collecting data on energy demand, shortfalls, production, and imports from past years. This data is analyzed to predict future energy demand. Energy planning is a key part of a country’s energy strategy to ensure uninterrupted energy supply to consumers in both the short and long term.

Q. What is least-cost end-use energy planning?

Answer: Least-cost end-use energy planning is an approach to energy planning that focuses on determining the most efficient way to provide energy services. Instead of asking how to supply more energy, the approach begins by identifying what energy services are needed and then seeks the most efficient methods to deliver those services.

Q. What are the criteria for alternative fuels to be widely used?

Answer: Alternative fuels must meet the following criteria to be widely used:

• Technical acceptability
• Economic competitiveness
• Environmental acceptability
• Safety and availability

Q. What are some examples of alternative fuels that can replace petroleum-based fuels?

Answer: Examples of alternative fuels that can replace petroleum-based fuels include:

• Alcohol (ethanol and methanol)
• Hydrogen
• Fuel cells

Q. What is ethanol?

Answer: Ethyl alcohol (CH₃CH₂OH), or ethanol, is a clear, colourless liquid with a characteristic odour. It is a liquid fuel made from sugar and grain crops by fermentation and distillation.

Q. Why must water be removed from fuel ethanol?

Answer: In order for fuel ethanol to work effectively as an alternative among fuel sources, all traces of water must be removed because water and alcohol combined cannot dissolve in gasoline.

Q. What are the advantages of ethanol?

Answer:

• It reduces air pollution.
• It reduces dependence on imported fuels.
• It is applicable for both light and heavy vehicles.
• Maintenance assistance required is more or less identical to that of conventional fuels.

Q. What is methanol?

Answer: Methyl alcohol (CH₃OH), or methanol, is an alcohol fuel. Methanol is methane with one hydrogen molecule replaced by a hydroxyl radical (OH). It can be produced from natural gas, wood, wood wastes, agricultural wastes, and sewage sludge.

Q. What are the advantages of methanol?

Answer:

• It has very low ozone-forming potential.
• It has low emissions.
• Emissions of sulphur and sulphur compounds are negligible.

Q. What is hydrogen and how is it produced?

Answer: Hydrogen is one of the simplest and lightest fuels. It produces only water vapour upon combustion. It can be easily prepared by electrolysis of water and is also obtained as a by-product in many industrial processes.

Q. What are the advantages of hydrogen?

Answer:

• It produces very few emissions.
• It has high energy content.
• It has a high octane rating.

Q. What are fuel cells?

Answer: Fuel cells are power-generating devices that electrochemically convert the chemical energy of a fuel to electricity. Since there is no combustion involved, their efficiency is much higher than that of heat engines.

Q. How do fuel cells work?

Answer: In fuel cells, electricity is generated when hydrogen and oxygen react. Hydrogen is fed to the anode and oxygen to the cathode, resulting in the production of electricity and water.

Q. What are the advantages of fuel cells?

Answer:

• They have low emissions compared to conventional vehicles.
• They are modular and can be shaped to fit available space.
• Since chemical energy is directly converted to electricity, no energy is lost to heat.
• They are two to three times more efficient than internal combustion engines in converting fuel to power.

Q. How does nanotechnology enhance energy efficiency?

Answer: Nanotechnology helps develop efficient thermoelectric elements that directly produce power from heat, and micro-turbines and micro-engines capable of running on ethanol and methanol. These micro-engines can generate power to light a household through LED lamps.

Q. What improvements in chulhas help conserve energy?

Answer:

• Efficient generation of heat through efficient wood burning.
• Efficient transmission of heat to the cooking pot.
• Retention of heat in the chulha to minimise heat loss.

The chimney also eliminates smoke, providing a healthy cooking environment.

41. How can energy be saved in electric irrigation pumps in India?

Answer: Replacing high-friction components like foot valves with low-friction ones in India’s electric irrigation pumps could save 35% of the electricity they use, which would save more than 2000 MW of power.