THEORY EXAMINATION (SEM–VIII) 2016-17 NON CONVENTIONAL ENERGY RESOURCES

Non-Conventional Energy Resources – Section Wise Explanation

Section A – Basic Concepts of Renewable Energy

Section A focuses on basic theoretical concepts of non-conventional energy resources. These questions are short and are meant to test a student’s fundamental understanding of renewable energy technologies. 

Non-conventional energy resources are alternative energy sources that do not rely on fossil fuels. These include solar energy, wind energy, geothermal energy, tidal energy, biomass energy, and ocean thermal energy. These sources are considered environmentally friendly because they produce less pollution and help reduce global warming.

One of the concepts mentioned in this section is the Seebeck Effect and Peltier Effect, which are related to thermoelectric energy conversion. These effects explain how temperature differences can generate electricity or how electricity can create temperature differences.

Another important concept is the solar constant, which represents the amount of solar energy received per unit area outside the Earth's atmosphere. It is important in designing solar energy systems.

The section also discusses energy conservation and energy audit, which help industries and organizations reduce energy consumption and improve efficiency.

Concepts such as wind turbine efficiency, solar collector efficiency, and OTEC (Ocean Thermal Energy Conversion) highlight how renewable energy technologies convert natural resources into usable power.

Understanding these basic concepts is essential for engineers who want to work in renewable energy systems.

Questions for Section A

What are Seebeck Effect and Peltier Effect? Explain their importance in thermoelectric systems.

What chemical reaction occurs in an Alkaline Fuel Cell?

What is aerobic digestion and how is it useful in biomass energy production?

Define solar constant and state its standard value.

Explain the concepts of energy conservation and energy audit.

What is the maximum theoretical efficiency of a wind turbine?

Define Fill Factor in solar cells.

What factors affect the efficiency of a flat plate solar collector?

What is Ocean Thermal Energy Conversion (OTEC)?

Describe the different types of geothermal energy resources.

Section B – Intermediate Concepts of Renewable Energy Systems

Section B requires students to explain renewable energy systems in detail. Students must attempt any five questions from this section. 

This section focuses on different renewable energy technologies and how they work. Renewable energy is becoming increasingly important because fossil fuels are limited and contribute significantly to environmental pollution.

Solar energy is one of the most widely used renewable energy sources. Solar collectors convert sunlight into heat energy, which can then be used for water heating or electricity generation. The flat plate solar collector is one of the most common solar thermal devices because of its simple design and low cost.

Another important topic discussed in this section is photovoltaic cells (PV cells). These cells convert sunlight directly into electricity through the process of photoconduction. PV cells are widely used in solar panels for residential and commercial electricity generation.

Biomass energy is another renewable energy source that uses organic materials such as agricultural waste, animal waste, and plant residues to produce energy. Through processes like gasification and anaerobic digestion, biomass can be converted into useful fuels like biogas.

Tidal energy is generated by harnessing the movement of ocean tides. Systems such as single basin and two basin tidal power plants are used to capture this energy and convert it into electricity.

Fuel cells are another innovative energy technology. In a hydrogen-oxygen fuel cell, hydrogen reacts with oxygen to produce electricity, with water as the only by-product. This makes fuel cells a clean and efficient energy source.

Another advanced system mentioned in this section is Magnetohydrodynamic (MHD) power generation, which generates electricity by moving ionized gases through a magnetic field.

Questions for Section B

Explain the main features of renewable and non-renewable energy sources.

Why are non-conventional energy sources important in controlling global warming?

Describe the construction and working of a flat plate solar collector.

Explain the mechanism of photoconduction in photovoltaic cells.

Describe the process of biomass gasification and its applications.

Explain the working of tidal power plants using single basin and two basin systems.

Describe the working principle of a hydrogen-oxygen fuel cell.

Explain the working of a closed cycle MHD power generation system.

Describe the production of biogas from biomass.

Explain the design and operation of the Deen Bandhu Biogas Plant.

Section C – Advanced Topics in Renewable Energy

Section C contains advanced questions that require detailed explanations and analytical understanding of renewable energy technologies. Students are required to attempt any two questions. 

One of the major topics in this section is wind energy. Wind turbines convert the kinetic energy of wind into mechanical energy and then into electrical energy. The Betz limit defines the maximum theoretical efficiency of a wind turbine. According to the Betz model, no wind turbine can convert more than about 59.3% of the wind’s kinetic energy into useful power.

Another advanced topic is solar cell arrays, which are groups of photovoltaic cells connected together to produce higher voltage and power levels. These arrays are commonly used in solar power plants and rooftop solar installations.

The section also discusses vertical axis wind mills (VAWT), which are wind turbines with blades that rotate around a vertical axis. These turbines are suitable for areas with variable wind directions.

Another important technology mentioned is the thermionic generator, which converts heat energy directly into electrical energy using thermionic emission. This technology is different from thermoelectric generators, which rely on temperature differences to produce electricity through the Seebeck effect.

Understanding these advanced systems helps engineers design more efficient renewable energy technologies.

Questions for Section C

What are the best locations for installing wind turbines?

Explain the Betz model of wind turbines and derive the expression for wind power extraction.

Under what conditions can maximum power be extracted from a wind turbine?

What practical problems are associated with MHD power generation?

Explain the concept of solar cell arrays.

Describe the structure and working of vertical axis wind mills.

Explain the construction and working of thermionic generators.

What is the difference between thermoelectric and thermionic energy conversion systems?

Conclusion

The Non-Conventional Energy Resources exam paper evaluates knowledge at three levels. Section A focuses on fundamental concepts such as solar energy, wind energy, and geothermal energy. Section B examines detailed understanding of renewable energy technologies and their working principles. Section C evaluates advanced analytical knowledge related to wind turbines, solar arrays, and thermionic generators. 

Understanding these topics is essential because renewable energy technologies are becoming increasingly important for sustainable development and reducing environmental pollution.