Electrical energy is very vital in recent times and modern living. In the day-to-day running of businesses and homes, we need energy at least to power our appliances. In south-eastern geopolitical zone of Nigeria, we have coal, oil and gas in abundance. MHD electrical power generation technology is one the technologies many developing countries apply to alleviate electrical power problems. This work therefore studied some MHD configurations that will perform optimally best with reference to the available coal and gas in southern Nigeria. These naturally available resources can be harnessed towards boosting electrical power generation. The study investigated the performance of different plant configurations based on open-cycle MHD generators fed with coal and gas. The power plants analysis has been performed by developing an integrated model required to characterize mass and energy balances of each system component and the electro-magnetic equations needed to solve the energy balance in the MHD generator. System efficiency was achieved by considering the IG-MHCC, B plant configuration where a high temperature heat recovery level has been introduced.

1. International Journal of Electrical, Electronics and Computers (EEC Journal) [Vol-1, Issue-3, Sep-Oct, 2016]
ISSN: 2456-2319
www.eecjournal.com Page | 1
Performance Evaluation of MHD Renewable
Energy Source for Electric Power Generation in
Nigeria
Dr. Mgbachi C.A.
Electrical and Electronics Engineering Department. Enugu State University of Science and Technology, ESUT, Enugu-
Nigeria.
Abstract— Electrical energy is very vital in recent times
and modern living. In the day-to-day running of businesses
and homes, we need energy at least to power our
appliances. In south-eastern geopolitical zone of Nigeria,
we have coal, oil and gas in abundance. MHD electrical
power generation technology is one the technologies many
developing countries apply to alleviate electrical power
problems. This work therefore studied some MHD
configurations that will perform optimally best with
reference to the available coal and gas in southern Nigeria.
These naturally available resources can be harnessed
towards boosting electrical power generation. The study
investigated the performance of different plant
configurations based on open-cycle MHD generators fed
with coal and gas. The power plants analysis has been
performed by developing an integrated model required to
characterize mass and energy balances of each system
component and the electro-magnetic equations needed to
solve the energy balance in the MHD generator. System
efficiency was achieved by considering the IG-MHCC, B
plant configuration where a high temperature heat recovery
level has been introduced.
Keywords— Magneto Hydrodynamics (MHD), plasma.
I. INTRODUCTION
Magneto Hydrodynamics (MHD) is one of the numerous
renewable electrical energy sources in research nowadays.
Electrical energy is very vital in recent times and modern
living. In the day to day running of business, we need
energy to power our home, illumination is very important in
order to avoid darkness throughout the day. Some
crumbling of businesses is as result of electrical energy
failure. Recently we heard that Nigeria mega watts had drop
from 4000mw to 1000gmw which is not enough to power
our homes and industries. This poses serious threat to our
economy. In order to boost power supply, the present
administration encourages research and development in
other find out other electrical power generators to
complement the present grid capacity. In southern part of
Nigeria, we have coal, oil and gas in abundance. This work
therefore studies how these naturally available resources
can be harnessed towards boosting our electrical power
stability.
Magneto Hydrodynamics (MHD) electrical power
generation has some promising features that encourages our
desire. We therefore study it under the following:
(1) Magneto Hydrodynamics (MHD) power generation
principle.
(2) Gas powered generation.
(3) Coal powered generation.
(4) Combine cycled.
(5) HRSG.
II. PRINCIPLES & CONFIRGURATIONS
MHD is a method of extracting electrical energy from heat
energy. The heat energy is from conventional fuel
combustion system. The principle of MHD is based on
Faraday’s law of electromagnetic induction, which states
that when a conductor and a magnetic field moves relative
to each other then voltage is induced in the conductor,
which results in flow of current across the terminals.
As the name implies the magneto hydro dynamics generator
is concerned with the flow of a conducting fluid (plasma) in
the presence of magnetic and electric fields. In conventional
generator or alternator, the conductor consists of copper
windings or strips while in an MHD generator, the hot
ionized gas or conducting fluid replaces the solid conductor.
The pressurized electrically conducting fluid, “plasma”
flows through a transverse magnetic field in a channel or
duct (see figure 1.1).

2. International Journal of Electrical, Electronics and Computers (EEC Journal) [Vol-1, Issue-3, Sep-Oct, 2016]
ISSN: 2456-2319
www.eecjournal.com Page | 2
Fig.1.1: The typical open cycle scheme for coal-fired MHD
systems
Pairs of magnetic electrodes are located on the channel
walls at right angle to the magnetic field and connected
through an external circuit to deliver power to a load
connected to it.
Electrodes in the MHD generator perform the same function
as brushes in a conventional DC generator. The MHD
generator develops DC power and the conversion to AC is
done using an inverter.
The power generated per unit length by MHD generator is
approximately given by
БUB2
/P;
Where;
U is the fluid velocity.
Б is the electrical conductivity of conducting fluid.
P is the density of fluid.
It is evident from the equation above, that for the higher
power density of an MHD generator, there must be a strong
magnetic field of 4-5 tesla and high flow velocity of
conducting fluid besides adequate conductivity.
The flow (motion) of the conducting plasma through a
magnetic field causes a voltage to be generated (and an
associated current to flow) across the plasma, perpendicular
to both the plasma flow and the magnetic field according to
Fleming’s Right Hand rule.
Lorentz law describing the effects of a charged particle
moving in a constant magnetic field can be stated as
F = Q V B
Where
F = Force acting on the charged particle
Q = Charge of particle
V = Velocity of particle
B = Magnetic field
MHD CYCLES AND WORKING FLUIDS
The MHD cycles can be of two types, namely: Open and
closed cycle MHD.
The detailed account of the types of MHD cycles and the
working fluids used is given below.
OPEN CYCLE MHD SYSTEM
In open cycle MHD system, atmospheric air at very high
temperature and pressure in passed through the strong
magnetic field. Coal is first processed and burnt in the
combustor at a high temperature of about 2700o
C and
pressure about 12 at p with pre-heated air from the plasma.
Then a seeding material such as potassium carbonate is
injected to increase the electrical conductivity. The resulting
mixture having an electrical conductivity of about 10
Siemens/m is expanded through a nozzle, so as to have a
high velocity and then passed through the magnetic field of
MHD generator. During the expansion of the gas at high
temperature, the positive and negative ions move to the
electrodes and thus constitute an electric current. The gas is
then made to exhaust through the generator. Since the same
air cannot be reused again hence it forms an open cycle and
this is named as OPEN CYCLE MHD.
CLOSED CYCLE MHD SYSTEM
As the name suggests, the working fluid in a closed cycle
MHD is circulated in a closed loop. Hence, in this case inert
gas or liquid metal is used as the working fluid to transfer
the heat. The liquid metal has typically the advantage of
high electrical conductivity hence the heat provided by the
combustion material need not be too high. Contrary, to the
open loop system there is no inlet and outlet for the
atmospheric air. Hence the process in simplified to a great
extent, as the same fluid is circulated time and again for
effective heat transfer.
MHD POWER PLANT CONFIRGURATION.
The conventional Coal Fired Magneto Hydrodynamic
Combined Cycle, (CF-MHCC) based on a MHD generator
integrated with a steam turbine power plant;
• The advanced Integrated Gasification Magneto
Hydrodynamic Combined Cycle, (IG-MHCC) is based
on a MHD generator integrated with a steam turbine
power plant;
• The advanced IG-MHCC, B in which the MHD
generator is integrated with a steam turbine power
plant and a closed gas turbine cycle fed with nitrogen.
The coal is sent to the combustion chamber (CC) that is fed
by air enriched with oxygen (generated in the Air
Separation Unit) to reach the temperature for plasma
generation. The combustion products, seeded with

3. International Journal of Electrical, Electronics and Computers (EEC Journal) [Vol-1, Issue-3, Sep-Oct, 2016]
ISSN: 2456-2319
www.eecjournal.com Page | 3
potassium carbonate in order to increase the plasma
conductivity, enter the MHD generator where
Electrical power is produced and leaves the system at high
temperature and pressure close to the atmospheric one. The
thermal power available from the MHD exhausts is used to
generate steam and, in order to enhance the overall system
efficiency, to preheat the combustion air in a heat exchange.
III. MHD PLANT SYSTEM MODELLING
The MHD generator model
The MHD generator for this work consists of a combustion
chamber in which, in order to reach the temperature for
plasma generation, the feeding fuel is oxidized by air and
seeded to increase its conductivity, a nozzle where the
plasma is accelerated up to the specified Mach number, the
MHD duct (immersed in a magnetic field and equipped by
electrodes placed on walls parallel to the magnetic field
itself) where the plasma is expanded and the electric power
is extracted, and a diffuser in which the kinetic energy of
the plasma is converted to the energy pressure to achieve
the required outlet conditions.
IV. RESULTS AND CONCULSION
The power generated by the MHD generator increases with
the air preheating temperature due to the greater plasma
mass flow moving across the system.
Moreover the power produced in the steam power plant
decreases slightly with the increasing in the air combustion
temperature because the input thermal power available is
almost constant (the reduction of thermal gradient is
covered by the greater mass flow rates of the MHD
exhausts). The system efficiency ranges from 39.4% to 51%
meaning that at higher air preheating temperature a better
heat recovery is realized. With respect to the CFMHCC
plant the efficiency penalty of IG-MHCC,A is very low
resulting less than 2%.
An improvement of system efficiency is expected by
considering the IG-MHCC, B plant configuration. In this
case, a high temperature heat recovery level has been
introduced.
Results show that the system efficiencies are enhanced in
the whole air preheating temperature range, achieving a
maximum value of 60%.
Conclusion
The aim of this paper was to investigate the performance of
different plant configurations based on open-cycle MHD
generators fed with coal and gas readily available in African
communities. The power plants analysis has been
performed by developing an integrated model required to
characterize mass and energy balances of each system
component and the electro-magnetic equations needed to
solve the energy balance in the MHD generator.
Results show that the heat re-circulation to the combustion
chamber (the thermal energy transferred to the air
combustion by the cooling of MHD exhausts) has a
significant impact on system efficiency.
In order to improve the system efficiency a high
temperature heat recovery level has been introduced in the
plant configuration by using a closed gas turbine cycle.
Results show that the system efficiencies are enhanced,
0
2
4
6
8
10
12
P-
MHD(MW)
P-
PSU(MW)
P-
EXP(MW)
Air
Temp.
( *C)
Power Balance
PMHD PSPU EXP.
(-------MW------)
System
Efficiency
(%)
1000 6.29 6.42 1.59 39.4
1200 6.77 6.32 1.59 41.2
1400 7.58 6.21 1.59 44.8
1600 8.58 6.11 1.59 48.1
1800 9.82 5.94 1.59 51.0
Air
Temp.
( *C)
Power Balance
PMHD PSPU+
EXP.
(MW)
System
Efficiency
(%)
1000 6.29 9.50 1.59 50.7
1200 6.77 9.35 1.59 52.4
1400 7.58 9.21 1.59 55.8
1600 8.58 9.07 1.59 59.0
1800 9.82 8.40 1.59 60.0

4. International Journal of Electrical, Electronics and Computers (EEC Journal) [Vol-1, Issue-3, Sep-Oct, 2016]
ISSN: 2456-2319
www.eecjournal.com Page | 4
achieving a maximum value of 60%. This means that higher
system efficiencies could be further obtained by optimizing
the working conditions.
REFERENCES
[1] Perna A. Combined power and hydrogen production
from coal. Part A: Analysis of IGHP plants. Int J
Hydrogen Energ 2008;33:2957-64
[2] Cicconardi SP, Perna A, Spazzafumo G. Combined
power and hydrogen production from coal. Part B.
Comparison between the IGHP and CPH systems. Int
J Hydrogen Energ 2008;33:4397-404
[3] Minutillo M, Perna A. A Novel Approach for
Treatment of CO2 From Fossil Fired Power Plants.
Part A: The Integrated Systems ITRPP. Int J
Hydrogen Energ 2009;34:4014-20
[4] Minutillo M, Perna A. A Novel Approach for
Treatment of CO2 From Fossil Fired Power Plants.
Part B: The energy suitability of ITRPPs for methanol
production. Int J Hydrogen Energ 2010;33:7012-20
[5] Rosa RJ. Magnetohydrodynamic energy conversion.
Washington, DC: Hemisphere, 1987
[6] Kayukawa N. Open-cycle magnetohydrodynamic
electrical power generation: a review and future
perspectives. Prog Energ Combust 2004:30; 33–60
[7] Satyamurthy P, Venkatramani N, Quraishi AM,
Mushtaq A. Basic design of a prototype liquid metal
magnetohydrodynamic power generator for solar and
waste heat. Energy Conv Mgmt 1999;40:913-35
[8] Ibáñez G, Cuevas S, López de Haro M. Optimization
of a magnetohydrodynamic flow based on the entropy
generation minimization method. Int Commun Heat
Mass Trans 2006;33:295–301
[9] Hishikawa M, Mifune T, Jianzhong T. Two
dimensional analysis of coal-fired
magnetohydrodynamic Faraday generator at IEE,
China Energy Convers Mgmt 2001; 42:1459-75
[10]Harada N, Kien LC, Hishikawa M. Basic Studies on
Closed Cycle MHD Power Generation System for
Space Application.35th AIAA Plasmadynamics and
Lasers Conference 28 June-1 July 2004.
Portland,Oregon
[11]Ishikawa M, Steinberg M. MHD power systems for
reduction of CO2 emission. Energy Conv Mgmt
1998;39:529-39
[12]Cicconardi SP, Jannelli E, Spazzafumo G. MHD
plants: a comparison between two-level and three-
level systems. Energy Convers Mgmt 1997;38(6):525-
31
[13]Kayukawa N. Comparisons of MHD topping
combined power generation systems. Energy Convers
Mgmt 2000; 41(18):1953 -74
[14]Kribus A. A high-efficiency triple cycle for solar
power generation. Sol Energy 2002;72(1): 1-11
[15]Aithal SM. Characteristics of optimum power
extraction in a MHD generator with subsonic and
supersonic inlets. Energy Convers Mgmt 2009;50(3)
765-71