Subject:-Renewable Energy Engineering MHD Power Generation

1. MHD POWER
GENERATION
Sigma institute of engineering and technology
Subject:-Renewable Energy Engineering(2181910)
Active Learning Assignment (ALA)

2. Present by:-
Name Enrollment no.
Ranjane Rohan V. 160503119059
Shah Bhavya V. 160503119063
Panchal Jaydeep B. 160503119033
Gandhi vivake D. 160503119015
Jha Pankaj S. 160503119034
Guide by:-
Tejal Rana.Semester:-8th (M82)

3. Content
■ Introduction
■ Principle of MHD Power Generation
■ Method of MHD Power Generation
■ Open cycle system
■ Closed cycle system
■ Advantages
■ Disadvantages

4. Introduction
■ Magneto hydro dynamic (MHD) principle is applied for
generating power from coal fired or reactor power plants.
■ MHD generator plant does not require any turbine and does not
have any generator shaft. In a MHD generator the thermal
energy is directly converted to electrical energy.
■ MHD generator is a heat engine operating on turbine cycle and
transforming the internal energy of gas directly into electrical
energy.

5. Principle of MHD Power Generation
■ Faraday’s Law of
Electromagnetic
Induction:- When an
electric conductor
moves across a
magnetic field, a voltage
is induced in it, which
produces an electric
current .

6. Method of MHD Power Generation
■ Open cycle system
■ Closed cycle system
1. Seeded inert gas MHD generator
2. Liquid metal MHD system
Khibiny generator. Capacity=120 MW,Working medium mass
flow rate=200kg/s

7. Open cycle system
 Fossil fuel (coal) is burnt to very high temperature in the furnace to very high
temperature to achieve ionized gas. The electrical conductivity of the plasma is
increased by seeding the gas by addition of potassium or cesium. High
conductivity plasma is accelerated through the MHD tunnel convergent-
divergent portion of the nozzle shaped tunnel.

8. ■ The pressure ratio (P1/P2) from high pressure side to low pressure side to
nozzle throat is so high and angle of divergence of tunnel is such that
very high gas velocity is achieved in divergent portion. Conductive gas
passes through the magnetic field B of the MHD generator.
■ The MHD generator delivers DC electric power through its electrode
system. Heat from hot exhaust gases can be recovered further in the heat
recovery chamber. Heat is supplied to heat exchanger to produce steam
for steam turbine which drives auxiliary generator.
Open cycle system

9. Closed cycle system
■ Two general types of closed cycle MHD generators are being investigated.
■ Electrical conductivity is maintained in the working fluid by ionization of a
seeded material, as in open cycle system.
■ A liquid metal provides the conductivity.

10. ■ Two working fluids are used, one for liquid metal & the other for inert
gases.
■ Liquid metal is heated by coal fired plant or nuclear reactor plant. Heating
by liquid metal causes the expansion of inert gases.
■ The mixture of inert gas & liquid metal is passed through MHD tunnel.
■ The gas expanding in the tunnel gets accelerated & increases the velocity
of the mixture.
■ The liquid metal acts as a moving conductor in the tunnel. After passing
through the MHD generator, the two fluids are separated again. The
liquid metal is reheated. The gas is cooled & recompressed. Both the
working fluids are recirculated again.
Closed cycle system

11. Advantages
■ MHD-steam hybrid plant is efficient as around 50-60%.
■ This system have no moving part.
■ This system more reliable
■ It has ability to reach the full power level instantly.
■ Maintenance cost is low.
■ Cost of power generation per unit is less.
■ Coal, oil, solar, nuclear can be used with the MHD generator.

12. Disadvantages
■ MHD equipment's have shorter life due to high temperature stresses.
■ It has high fluid friction losses and heat transfer losses.
■ It has very high operating temperature, which restrict the choice of
material for various equipment's.
■ There are technical limitation on enhancing the fluid conductivity and
strength of the magnetic field.

13. THANK YOU