Course Number ENGG-243 offers an essential exploration into the field of renewable energy and green technology specifically designed for agriculture graduates. This course serves as a comprehensive introduction to the principles, applications, and innovations in sustainable energy systems and environmentally friendly technologies that are revolutionizing the agricultural sector. Students will gain a solid foundation in renewable energy sources such as solar, wind, biomass, and hydropower, along with an understanding of their integration into agricultural practices. Moreover, they will delve into the latest advancements in green technologies, including precision farming, smart irrigation systems, biofuel production, and sustainable waste management. Through a combination of theoretical learning and practical exercises, students will acquire the knowledge and skills necessary to harness the power of renewable energy and implement eco-friendly solutions within the realm of agriculture, contributing to a more sustainable and resilient future.

1. ENGG 243
Renewable Energy and
Green Technology
Other Renewable Energy Sources
(Ocean thermal energy)
Dr. Ganesh N. Shelke
Agricultural Engineer
(Process & Food Engineering)
Mob. No. +91 9561777282/ 8605957182
Email: shelkeganesh838@gmail.com

2.  Ocean thermal energy, also known as OTEC (Ocean Thermal
Energy Conversion), is a renewable energy technology that
harnesses the temperature difference between warm surface
waters and cold deep waters of the ocean to generate
electricity.
 OTEC utilizes the temperature gradient in the ocean to produce
electricity.
 It is a sustainable and renewable energy source with a vast
potential for power generation.
 OTEC systems can provide baseload power, offering a constant
and reliable energy supply.
 OTEC helps reduce carbon footprint as it emits no greenhouse
gases during operation.
Ocean thermal energy (OTEC)

3.  Components of Ocean Thermal
Energy Conversion (OTEC)
 Surface Water Intake System:
Collects warm surface water for the
OTEC plant.
 Vacuum Chamber: Evaporates
warm water under reduced pressure.
 Turbine: Driven by expanding
vapor, it generates mechanical
energy.
 Generator: Converts the turbine's
rotational motion into electricity.
 Condenser: Cools down the vapor,
causing it to condense back into a
liquid state.
 Cold Water Pipeline: Transports
cold water from the deep ocean for
condensation and cooling.
Ocean thermal energy (OTEC)

4.  Warm surface water is drawn from the ocean
using a pipe or intake system.
 The warm water is placed in a low-pressure
vacuum chamber, causing it to boil at a lower
temperature and evaporate.
 The vapor formed through evaporation expands
and drives a turbine.
 The turbine is connected to a generator to
produce electricity.
 After passing through the turbine, the vapor is
cooled using cold water from the deep ocean.
 The cooling process causes the vapor to
condense back into a liquid state.
 The cold water, having absorbed the heat from
the vapor, is discharged back into the ocean
through a separate outlet, completing the cycle.
Ocean thermal energy (OTEC)

5. Ocean thermal energy (OTEC)
Advantages Disadvantages
Renewable and
Sustainable
High Initial Costs
Abundant Resource Location Dependency
Baseload Power
Generation
Potential
Environmental Impact
Environmentally
Friendly
Technical Challenges
Potential for
Desalination
Limited Efficiency

6. ENGG 243
Renewable Energy and
Green Technology
Other Renewable Energy Sources
(Tidal energy)
Dr. Ganesh N. Shelke
Agricultural Engineer
(Process & Food Engineering)
Mob. No. +91 9561777282/ 8605957182
Email: shelkeganesh838@gmail.com

7.  Tidal energy is a form of renewable energy that harnesses
the power of tides, which are caused by the gravitational
pull of the moon and the sun.
 It is an emission-free energy source, contributing to a
reduced carbon footprint.
 Tidal energy has a high energy density, offering significant
power generation potential.
 Tidal energy systems have a long operational lifespan and
can stimulate local economies through job creation.
 However, tidal energy is location-dependent and can impact
marine ecosystems, requiring careful planning and
mitigation measures.
Tidal energy

8.  The working principle and components of tidal
energy
 Tidal Barrage: A tidal barrage is a dam-like structure built across
a bay or estuary, with turbines installed.
 Tidal Flow: As the tide rises, water enters the barrage through
sluice gates, and as the tide falls, the gates close to trap the water
inside.
 Power Generation: When the tide reaches its peak, the water in
the barrage is released through turbines. The water flow turns the
turbines, which drives generators to produce electricity.
 Reversal of Flow: As the tide changes, the direction of flow is
reversed, and the water outside the barrage is allowed to flow
back to the sea.
Tidal energy

9. Tidal energy
Advantages Disadvantages
Renewable and Predictable Limited Locations
Emission-Free Environmental Impact
High Energy Density High Capital Costs
Long Lifespan Maintenance Challenges
Job Creation and Economic
Benefits
Navigation and Shipping
Interference

10. ENGG 243
Renewable Energy and
Green Technology
Other Renewable Energy Sources
(Geothermal Energy)
Dr. Ganesh N. Shelke
Agricultural Engineer
(Process & Food Engineering)
Mob. No. +91 9561777282/ 8605957182
Email: shelkeganesh838@gmail.com

11.  Geothermal energy is a renewable and
sustainable energy source from the heat
generated within the Earth's core.
 It harnesses the natural heat of the Earth for
various applications, including electricity
generation and heating/cooling systems.
 The Earth's core contains exceptionally high
temperatures, reaching 5,500 degrees
Celsius (9,932 degrees Fahrenheit).
 Heat is continuously generated within the
Earth through processes such as radioactive
decay and residual heat from its formation.
Geothermal Energy

12.  The working principle of geothermal energy involves
tapping geothermal reservoirs to extract heat and convert it
into usable energy.
 This is typically done through geothermal power plants,
which utilize different technologies depending on the
availability of resources:
 Different technologies are used depending on the resource
availability:
 Dry Steam Power Plants: Use high-pressure steam to
generate electricity.
 Flash Steam Power Plants: Convert high-pressure hot water
into steam to generate electricity.
 Binary Cycle Power Plants: Heat exchangers vaporize a
secondary fluid, which drives turbines to generate electricity.
Geothermal Energy

13. Geothermal Energy

14. Geothermal Energy
Advantages Disadvantages
Renewable and sustainable
source of energy
Limited to specific regions
with accessible reservoirs
Minimal greenhouse gas
emissions
High initial costs for
drilling and construction
Reliable and constant
energy supply
Potential environmental
impact
Long lifespan and low
maintenance
Possibility of seismic
activity
Versatile applications
Constraints on large-scale
implementation

15. ENGG 243
Renewable Energy and
Green Technology
Other Renewable Energy Sources
(Hydrogen Energy, Fuel cells)
Dr. Ganesh N. Shelke
Agricultural Engineer
(Process & Food Engineering)
Mob. No. +91 9561777282/ 8605957182
Email: shelkeganesh838@gmail.com

16.  Fuel cells are devices that generate electricity through an
electrochemical reaction between hydrogen (H2) and
oxygen (O2).
 Working principle (Steps):
1. Fuel and Oxidant Supply:
 Fuel cells require a fuel source and an oxidant (usually
oxygen or air) to operate.
 The most common fuel is hydrogen gas (H2), although
other fuels, such as methanol or natural gas, can also be
used.
 The oxidant, usually oxygen (O2) from the air, is
supplied to the fuel cell.
Hydrogen Energy Fuel cells

17.  Working principle (Steps):
2. Electrolyte and Electrodes:
 Fuel cells consist of an electrolyte and two
electrodes:
 Anode: The anode is the negative electrode
where the fuel, such as hydrogen gas, is
supplied.
 It typically contains a catalyst that helps in the
electrochemical reaction.
 Cathode: The cathode is the positive electrode
where the oxidant, usually oxygen, is supplied.
 It also contains a catalyst.
Hydrogen Energy Fuel cells

18.  Working principle (Steps):
3. Electrochemical Reactions:
 The electrochemical reactions occur at the anode and cathode,
 At the Anode: The hydrogen fuel (H2) is supplied to the anode. In the
presence of a catalyst, the hydrogen molecules are split into protons
(H+) and electrons (e-). The electrons are released and flow through
an external circuit, creating an electric current.
 Through the External Circuit: The flow of electrons from the anode
to the cathode through an external circuit creates the electrical current
that can be utilized to power electrical devices or charge batteries.
 At the Cathode: Oxygen (O2) from the air is supplied to the cathode.
The oxygen molecules combine with the protons (H+) that have
passed through the electrolyte and the electrons (e-) from the external
circuit. This combination produces water (H2O) as a byproduct.
Hydrogen Energy Fuel cells

19.  Working principle (Steps):
4. Electrolyte Function:
 The electrolyte serves as a medium that allows the
flow of ions between the anode and cathode while
preventing the direct mixing of the fuel and oxidant.
 It enables the movement of positively charged
hydrogen ions (protons) from the anode to the
cathode through the electrolyte.
Hydrogen Energy Fuel cells

20.  Working principle (Steps):
5. Electrical Output:
 The flow of electrons through the external circuit
generates electrical energy that can be used to power
various devices or systems.
6. Heat Generation:
 As a byproduct of the electrochemical reactions, fuel
cells also generate heat, which can be utilized in
combined heat and power (CHP) applications to
increase overall energy efficiency.
Hydrogen Energy Fuel cells

21. ENGG 243
Renewable Energy and
Green Technology
Other Renewable Energy Sources
(Hydroelectric)
Dr. Ganesh N. Shelke
Agricultural Engineer
(Process & Food Engineering)
Mob. No. +91 9561777282/ 8605957182
Email: shelkeganesh838@gmail.com

22.  Hydroelectric power, also known
as hydroelectricity or
hydropower, is a form of
renewable energy that harnesses
the energy of flowing or falling
water to generate electricity.
 The working principle of
hydroelectric power involves the
conversion of the potential energy
of water into mechanical energy
and then into electrical energy.
.
Hydroelectric

23. Water Source:
 Hydroelectric power plants are typically built
near water bodies such as rivers, dams, or
reservoirs.
 These water sources provide a constant or
seasonal flow of water that can be controlled
for power generation.
 Dam or Reservoir:
 A dam is often constructed across a river to
create a reservoir serving as a water storage
facility.
 The dam controls the flow of water and creates
a significant height difference or head,
representing the water's potential energy.
Hydroelectric

24. Penstock:
 A penstock is a large pipe or conduit that carries the
water from the reservoir to the turbine.
 The water pressure increases as it descends through the
penstock due to the dam's elevation difference or the
river's natural slope.
 Turbine:
 The penstock directs the high-pressure water to a
turbine. The turbine consists of blades or buckets that are
turned by the force of the flowing water.
 The water's kinetic energy is converted into mechanical
energy as the turbine rotates.
Hydroelectric

25. Generator:
 Connected to the turbine is a generator
consisting of a rotor and a stator.
 As the turbine spins, it drives the rotor
within the generator, creating a rotating
magnetic field.
 This movement induces electrical energy
generation in the stator windings through
electromagnetic induction.
 Transmission and Distribution:
 The electricity generated by the generator is
transmitted through power lines to
distribution networks, where it is further
transmitted to homes, businesses, and
industries for consumption.
Hydroelectric

26. Environmental Considerations:
 Hydroelectric power is a clean and renewable energy
source.
 It does not produce direct greenhouse gas emissions
during operation and does not require burning fossil
fuels.
 However, the construction of dams and reservoirs
can have environmental impacts, including changes
to ecosystems and displacement of communities.
 Proper planning and management are essential to
mitigate these effects.
Hydroelectric