Magneto hydrodynamics power generation

1. MAGNETO HYDRODYNAMICS
POWER GENERATION
Presented by:-
Potdar Pratik

2. INTRODUCTION
Magneto HydroDynamic (MHD) system is a non-
conventional source of energy which is based upon
Faraday’s Law of Electromagnetic Induction.
S
N
V Output current
Hot gaseous
conductor

3. Faraday’s law of electromagnetic induction : When an
electric conductor moves across a magnetic field, an
emf is induced in it, which produces an electric
current.
PRINCIPLE

4. Lorentz force law
• The Lorentz force law is the basis for the
Magnetohydrodynamic generator
• Charged particle expreineces a force when its moving in the
electromagnetic field. This force can be explained as
• F= Q (v xB)
Where, F is the force acting on charged
particle.
Q is the charge of the particle
V is the velocity of particle
B is the magnetic induction

5. HISTORY OF MHD
* The conversion process in MHD was initially described by
Michael Faraday in 1893.
* The first known attempt to develop an MHD generator was
made at Westing house researc laboratory (USA) around 1938.
* The first MHD-steam power plant U-25 was put into operation
was of 75MW unit in USSR of which 25MW is generated by
MHD means in early 1970’s & this work has been progressing
fruitfully
* The first pilot plant was set up in Tiruchirapalli (by BARC)
* In 1986, Professor Karl Messerle at The University of Sydney
researched coal-fueled MHD.
* At initial stage, efficiency was very low up to 10-20%.

6. • It has no moving parts & the actual
conductors are replaced by ionized
gas (plasma)
• The magnets used can be
electromagnets or superconducting
magnets.
• DC Superconducting magnets of
4~6Tesla are used.
• Plasma temperature is over 2000
°C.
• channel must be constructed from
an exceedingly heat-resistant
substance- Zirconium Dioxide.
• The electrode are made generally
using high temperature ceramic
materials such as carbides and
bromides.

7. WORKING PROCEDURE
• It converts the heat energy of fuel (thermal energy)
directly into electrical energy.
• By using a fuel like oil (or) natural gas (or) coal, the
fluid conductor is heated.
• Temperature in the combustion chamber is around
2000°K to 2400°K.
• The heat generated in the combustion chamber
removes the outermost electrons in the fluid
conductor
• Plasma is made to expand through a nozzle into the
generator.
• Magnetic field, a current is generated & it can be
extracted by placing electrodes,
• This generated EMF is DC.

9. Types Of Cycle
i. Open cycle MHD.
ii. Closed cycle MHD.
1) Open cycle MHD system.
Working fluid-potassium seed combustion
product. Temperature in OC MHD is about
2500oC. DC Superconducting magnets of
4~6Tesla are used. Here exhaust gases
are left out to atmosphere & the capacity
of these plants are about 100MW.

11. 2) Closed cycle MHD system

12. • Temperature of CC MHD plants is very
less compared to OC MHD plants. It’s
about 1400oC. DC Superconducting
magnets of 4~6Tesla are used. Here
exhaust gases are again recycled & the
capacities of these plants are more than
200MW.

13. ADVANTAGES
• These are less complicated than the conventional
generators, having simple technology.
• There are no moving parts in generator which reduces the
energy loss.
• These plants have the potential to raise the conversion
efficiency up to 55-60%. Since conductivity of plasma is
very high.
• It contribute greatly to the solution of serious air and
thermal pollution faced by steam plants.
• Ability to reach full power level as soon as started.
• Plant size is considerably smaller than conventional
fossil fuel plants

14. DISADVANTAGES
1. Suffers from reverse flow (short circuits) of electrons through the
conducting fluids around the ends of the magnetic field.
2. Needs very large magnets and this is a major expense.
3. They need high pure superconductor.
4. Working temperature is very high as about 200°K to 2400°K.
5. The components get high corrosion due to high working temperature.
6. Construction of generator is uneconomical due to its high cost.

15. APPLICATIONS
• The MHD generators are used to power submarines and
aircrafts.
• Electrical power production for domestic applications
• Power generation in space craft.
• They can be used as power plants in industry and
uninterrupted power supply system
• Currently being developed for cancer treatment.
• MHD is used to predict the inverting of the Earth’s magnetic poles.

16. ATTEMPTS FOR ELECTRICITY
GENERATION
1. BOSNIA: First experimental power
generator 1989
2. USA: A 50 MW programme
3. JAPAN: Pans for 5MW plant in
tokyo.
4. AUSTRALIA: 28MW Coal fueled
plant near sydney.
5. CHINA: In 1994 10MW plant to
support 108MW thermal power plant.
6. RUSSIA: In 1994 A 25 MW plant near
moscow