2. What is Renewable Energy
• It is the energy from a source that is not depleted when used, such as wind or solar power.
• Renewable energy is energy generated from natural resources —such as sunlight, wind, rain, tides and
geothermal heat—which are renewable (naturally replenished).
• Renewable energy technologies range from solar power, wind power, hydroelectricity/micro hydro,
biomass and biofuels for transportation.
3. Why Renewable Energy?
• Because of the desire and necessity to avert
irreversible climate damage
• Because of increasing oil prices
• In view of all these and other factors,
governments worldwide support renewables with
various incentives.
• Fossil fuels are non-renewable, that is, they draw
on finite resources that will eventually dwindle,
becoming too expensive or too environmentally
damaging to retrieve.
• Many types of renewable energy resources-such
as wind and solar energy-are constantly
replenished and will never run out.
• Abundant sunshine
Energy Consumption Trend
4. Renewable Resources
• Solar energy
• Wind energy
• Hydropower
• Heat Energy
• Biomass
There are many sources of renewable energy, but all
of them, except geothermal energy, are more or less
directly related to the sun: the main source of clean
and sustainable energy for the earth.
5. Solar energy
• Solar power is the technology of obtaining usable energy from
the light of the sun.
• Solar power energy has come into use where other power
supplies are absent, such as in places off from the
national electrical grid and in space.
• India’s solar grid had a cumulative capacity of
> 13.11 GW
• Solar energy is currently used in a number of applications:
• Heat (hot water, building heat, solar cooking)
• Electricity generation (photovoltaics and solar thermal, Stirling and
other heat engines)
• Desalination of seawater (taking the salt out so it can be used for
drinking or growing crops).
• Lightning
SOLAR PV PANNEL
SOLAR PV PANNEL TYPES
6. Pros and cons of Solar Energy
PROS
1. Clean Energy Source
2. Renewable and Sustainable
3. Power Remote Areas
4. Can be Installed on Rooftops
5. Reduce Electricity Bills
6. Availability
7. Low Maintenance
8. Silent
CONS
1. Initial Cost (Rs. 90-120 per watt)
2. Produce Power During Day
3. Solar Cells Effectiveness (14%-17%)
4. Large Area for Setup (10 sqm/kw)
5. Expensive Storage ( batteries )
7. Wind energy
• Wind power is using the energy of Wind has been used since
ancient times to move ships, and for hundreds of years to pump
water or grind corn and grain into flour, now it is usually changed
into electricity using wind turbines.
• As of the end of 2021 the total installed wind power
capacity was > 32.17 GW
• Most modern wind power is generated in the form of electricity
by converting the rotation of a turbine blades into electrical
current by means of an electrical generator.
8. Pros and cons of Wind Energy
PROS
1. Clean Source of Power
2. Renewable Source
3. Cost Effective
4. Extra Savings for Land Owners
5. Use of Modern Technology
6. Rapid Growth and Huge Potential
7. Can be Built on Existing Farms
CONS
1. Wind Reliability
2. Threat to Wildlife
3. Noise and Visual Pollution
4. Expensive to Set Up
5. Safety of People
6. Suitable to Certain Locations
7. Effect on Environment
9. Hydropower
• Hydropower is changing the energy of moving water into more
useful forms.
• Flowing water creates energy that can be captured and turned
into electricity. This is called hydroelectric power or hydropower.
• Today the largest use of hydropower is for a dam that can use the
falling water to make electricity.
• As of 30 April 2017, India's installed utility-scale hydroelectric
capacity was 44,594 MW.
10. Pros and cons of hydro power
PROS
1. Clean Source of Power
2. Renewable energy source
3. Cost competitive energy source
4. Contributes to development of remote
communities
5. Recreational opportunities
6. Fundamental vehicle for sustainable
development
CONS
1. Environmental damage
2. High upfront capital costs
3. Might cause conflicts
4. May lead to droughts
5. Risk of floods in lower elevations
6. Carbon dioxide and methane emission
11. Geothermal Energy
• This type of energy is obtained by tapping the heat of the earth,
which is mostly in the form of hot water and steam. Various
technologies are used to get to the heat under the earth’s surface
at different depths.
• In some areas of the planet geothermal energy is closer to the
surface and therefore easier to harness.
• Several metres under the earth’s surface the temperature is
between 10° and 16°C. In winter this heat can be brought to
buildings with pipes.
• Another technology uses deep wells in hot rock in which fluid is
heated to produce steam, which then drives turbines to generate
electricity. The facilities that enable this process are called dry
steam, flash steam and binary-cycle plants.
12. Pros and cons of Geothermal Energy
PROS
1. Renewable Source
2. Environment Friendly
3. No Fuel Needed
4. Abundant Supply
5. Significant Savings for Home Owners
6. Smallest Land Footprint
7. Innovation in Technology
CONS
1. Suitable to Particular Region
2. High Initial Costs
3. Cost of Powering the Pump
4. Surface Instability
5. Environmental Concerns
6. High Temperatures Needed
7. May Run Out of Steam
13. Biomass
• Biomass energy is the energy that is derived from organic matter of plants and animals.
• Some of this is burned to make electricity, some is made into biogas, biofuel, like ethanol as a replacement
for gasoline.
BIOMASS SOURCES
BIOPLANT PROCESS
14. Pros and cons of Geothermal Energy
PROS
1. Renewable Source
2. Dependency on Fossil Fuels is Reduced
3. Carbon Neutral
4. Widely Available
5. Can be Used in Many Forms
6. Helps Reduce Waste
CONS
1. Not Totally Clean When Burned
2. Can Lead to Deforestation
3. In-efficient
4. Requires Lot of Space
5. Expensive
15. • We can’t run out of renewables because nature
replenishes them faster than we consume them.
• The use of domestic power generators (e.g. solar
panels on the roof) reduces the strain on power
distribution systems.
• Green electricity is becoming increasingly
accessible to the average consumer.
• Renewables are generally not hazardous to the
environment.
• Biomass and geothermal energy need wise
management to avoid their depletion.
• Renewable heat is still expensive and hard to
access.
• Some green energy installations take up large
pieces of land that can be used to grow crops.
• If clean energy becomes prevalent, the electricity
transmission and distribution systems must be
transformed and managed more actively
large plant substation
power
transmission
power
distribution
consumer
This distribution is done to achieve economies of scale, or to bring energy generation closer to the resource
(e.g. mines) and away from populated areas (for health reasons). However, some of the energy, especially
heat, is lost during the transportation.
17. Need of Energy Storage In renewable
Energy
Energy storage technologies
The energy storage along with renewable energy generators/PV is
required to increase the reliability and flexibility.
The intermittent nature of renewable sources like solar and wind
needs storage to deliver the right amount of power at right quality.
To accommodate the projected high penetration of solar and
wind energy in future grids with lower grid rejection loss.
18. Energy storage technologies
Services of Energy storage technologies
EnergyArbitrate: Storing cheap off-peak energy and dispatching it as peak electricity
which requires large storage reservoir required at large capacity.
o Examples: Compressed air and pumped hydro
Load Regulation:
Responding to small changes in demand
Energy Storage technologies were suitable for load/frequency regulation due to
their high response time and high partial load efficiency.
They have to be
Highly reliable
Continuous change in output power
Suitable for frequent on-off
Examples: Flywheel, Ultra capacitors, Batteries
19. Energy storage technologies
Services of Energy storage technologies(cntd.)
Contingency Reserves: Mainly used as alternatives for
generators when there is transmission line trip or grid
failure.
These are categorised into three types:
– Spinning reserve: operates with in 10 min of outage
– Supplemental reserve: Comes into operation when spinning reserve is
fully discharged.
– Back up reserve:Acts as a back up in case of
spinning/supplemental reserve failure.
In all the services the load regulation service yields more revenue
but each storage technology can participate in more than one
market.
20. Energy storage technologies
Other services of Energy storage:
Load following: To fill the difference or gap between demand and supply.
– Difference between load following and load regulation is the time scale.
– The range for load regulation is a few seconds.
– The range for load following is with in minutes.
Capacity supply: The capacity supply reduces the investment for new thermal or other
conventional generation technologies. The investor could rent the storage capacity in the
market.
Transmission and distribution loss reduction: With the rise in demand new
transmission lines has to be set up which increases capital cost and the transmission
losses. Energy storage at the load centres resolves both of the problems.
21. Energy storage technologies-Categories
Power quality: Main purpose is frequency and voltage regulation.
Operating range: Seconds to few minutes
Examples: Flywheel, Ultra capacitors, SMES, Batteries
Bridging power: Main purpose is to act as contingency reserves and
ramping of load.
Operating range: Few minutes to one/two hour
Examples: High energy density batteries.
Energy Management: The main purpose is load following, Capacity
supply, Reduction of transmission and distribution losses.
Operating range: Few hours to days
Examples: CAES, pumped hydro storage
22. Energy storage technologies
Batteries
Batteries store energy chemically and uses electrochemical reactions to produce electricity
at a fixed voltage
Pros:
– Convenient voltage Characteristics
– Convenient sizing
– Extensive design history
Cons:
– Limited cycle life
– Voltage and current limitations, requiring complex series/parallel systems
– Often present environmental hazard
Battery Application Suitability
– Batteries are suitable for applications that require the supply of relatively large amounts of energy storage (>1
MWh) over long periods of time (15 minutes or more), where rapid recharge is not necessary and where
maintenance can be reasonably performed.
– They are not especially suitable for environmentally sensitive sites, remote locations, or applications that
require rapid discharge and absorption of energy.
23. Flywheel
Flywheels store energy in the form of momentum in a rotating wheel or cylinder.
Principle:
An electric motor spins the rotor to a high velocity to charge the flywheel.
During discharge, the motor acts as a generator, converting the rotational energy into electricity.
Power electronics are used to ensure that output voltage has appropriate voltage and frequency
characteristics
Pros:
– High power density
– High cycle life
– Quick recharge Independent
– power and Energy sizing
Cons:
– Low energy density
– Large standby losses
– Potentially dangerous failure modes
Energy storage technologies
24. Electro chemical/Super/Ultra capacitors
Electrochemical capacitors (EC), also known as super capacitors, ultra capacitors, or electrical
double-layer capacitors (EDLC), store energy in the electrical double layer at an
electrode/electrolyte interface.
Pros:
• High power density
• High cycle life
• Quick recharge
Cons:
• Low energy density
• Expensive
• Sloped voltage curve requires power electronics
• Energy and Power Density of Electrical Super capacitors:
• The energy and power densities of electrochemical capacitors fall between
those of batteries and conventional capacitors.
Energy storage technologies
25. Electrochemical Capacitor Technology Status
Currently viable for bridging power (seconds) in the hundreds of kW power range.
Smaller (several kW) power range, long term energy storage (hours) application of
electrochemical capacitors for residential peak shaving is another application that is
currently under consideration.
Use of ECs for multi-MW utility T&D applications that require several hours of energy storage
(peak shaving, load levelling, etc.) is not feasible at present.
Energy storage technologies