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COURSE NAME: PHYSICS OF RENEWABLE ENERGY SYSTEMS
Prof. AMREESH CHANDRA
DEPARTMENT OF PHYSICS, IIT KHARAGPUR
Module 5: Energy Storage
Lecture 20 : Introduction to Energy Storage Systems
CONCEPTS COVERED
⮚ Need for storage technology
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⮚ Various storage technologies
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⮚ Parameters used to compare various technologies
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KEY POINTS
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⮚ Understanding the meaning of intermittent nature
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⮚ Various areas of applications for the energy storage systems
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⮚ Classification of energy storage systems
Till now we have discussed about the following renewable
energy sources:
❖Solar Energy
❖Wind Energy
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❖Hydro Energy
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❖Tidal Energy
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❖Geothermal Energy
Each of these energy resources has its own advantages and limitations.
Solar energy:
Advantages:
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✓ Renewable
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✓ Environmental friendly
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✓ Diverse application
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✓ Low maintenance cost
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Limitations:
❑Intermittent
❑Weather dependent
❑High start up cost
❑Uses a lot of spaces
Wind energy:
Advantages:
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✓ Renewable
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✓ Clean
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✓ Low operating cost
Limitations:
❑Intermittent
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The wind farm Jaisalmer is the largest onshore wind farm in India, situated along
the river Yamuna, between the Vindhya and Himalayan mountains.
❑Noise and visual pollution
❑Some adverse environmental
impact
Hydro energy:
Advantages:
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✓ Clean and non-polluting source
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✓ Low maintenance cost
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✓ No fuel is required
Limitations:
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❑ Its impact on the local environment.
❑ Disruption to surrounding aquatic
ecosystems
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❑ It has relatively high constructional
costs
Tidal energy:
Advantages:
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✓ Renewable energy source
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✓ No green house gas production
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✓ Potential to deliver enormous
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amount of energy
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Limitations:
❑Location limitation
❑Very high topographical requirements
❑High input/ capital cost
❑Negative influence on marine life
Geothermal energy:
Advantages:
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✓ No release of green house gases
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✓ Renewable energy source
✓
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No fuel is needed
✓ Sustainable
Limitations:
❑ Location specific
❑ Highly expensive N P
❑ Release of harmful gasses deep within the earth
❑ It has the risk of triggering earthquakes
Some of the energy sources, which we have discussed till now:
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- can provide a continuous supply of energy
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while some others
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- produce energy intermittently!
QUESTIONS:
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SHOULD we operate the generation units only when the source is
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available?
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If we want to ensure energy safety, security and continuity then
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HOW to tackle the problem?
Need for storage technologies?
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❖ As we can see the renewable energy sources suffer from an intrinsic
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limitation i.e. “intermittency”.
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❖ There is a problem regarding secure supply for 24 hours a day and to
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create a balance between energy demand and supply
The answer lies in the
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USE OF A SUITABLE
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ENERGY STORAGE TECHNOLOGIES
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Need for storage technology
Ensure continuity
Ensure availability
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Restrict wastage
as per the need
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Counter the
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problem of
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Off grid Mobile
applications intermittency technologies
Bring balance
between supply
and demand
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So, you can see, the various types of energy storage systems, which we will be
studying in this course are:
Chemical energy
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Electrical
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Thermal energy
energy
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Mechanical
energy
Various storage systems and comparing relevant physical parameters
Round trip
Energy density
Forms of energy Energy Storage efficiency
(MJ/kg)
(%)
Fossil fuels, coal, oil 35 --
Chemical energy
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Hydrogen gas storage 140 ~60
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Hot water storage 0.13 >50
Thermal energy
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Ice-storage 0.33 ~80
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Potential energy Pumped hydroelectric .001 ~75
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Compressed air storage .33 ~50
Kinetic energy Fly wheels 0.04-0.4 ~80
Supercapacitors ~0.02 ~95
Superconducting magnets 0.001 95
Electrical energy
Lead acid battery 0.13 ~80
Fuel cells ~2 --
Mechanical energy storage:
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Pumped hydroelectric energy
storage N
Compressed air energy storage Flywheel Energy Storage
System
Thermal energy storage:
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Parabolic Trough Concentrator
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Electrical energy storage:
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Batteries
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Capacitors
Supercapacitors
Ref:
https://www.exideindustries.com
https://www.exportersindia.com/
Chemical energy storage:
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Microbial fuel cell
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You will see in later classes that:
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‘Each of these storage technologies have their own advantages,
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limitations and applicability’.
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Introducing some important parameters, which would be useful:
{more will be introduced as we go along}
1) Capacity: the amount of energy that is stored and the rate at which
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this energy can be delivered, i.e. power output.
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2) Energy density: the amount of energy stored per unit mass OR
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per unit volume.
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3) Round trip efficiency: the amount of energy that could be
extracted in comparison to the energy which was put in.
4) The time it takes to switch ON the power output.
You will also see that ‘materials’ will play a crucial role in making
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these technology useful for us.
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NANOTECHNOLOGY IS DRIVING THE
ADVANCEMENT OF TECHNOLOGIES.
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Confinement of NANOSTRUCTURES
z
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x
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CONCLUSION
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1) Need of energy storage technologies in renewable energy based
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landscape must be clear now.
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2) Various types of energy storage systems, which we will discuss in the
course, was also presented.
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3) Each of the energy storage technology has its own advantages and
limitations. Their use depends on the final application, which can be
quite varied!
REFERENCES
➢ Supercapacitors: an alternate technology for energy storage (2012)
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by Amreesh Chandra, Proceedings of the National Academy of Sciences, India Section A:
Physical Sciences, 82 Pages 79-90
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⮚ “Physics of Energy Sources” by George C. King
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➢ Energy Storage – Batteries and Supercapacitors Set (Vol. 1,2,3,4)
by Patrice Simon & Jean-Marie Tarascon
➢ Electrochemical Supercapacitors: Scientific Fundamentals and Technological Applications
by B.E. Conway.
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