Mechanical Engineering class lecture

1. Power Plant Engineering (ME 4505)
ENERGY SCENARIO
Prof. Dr. Md. Mostaqur Rahman
Department of Mechanical Engineering
DUET, Gazipur

2. Energy Scenario
Energy, that we use, can be classified into several types based on the following criteria:
 Primary energy and secondary energy:
Primary energy refers to all types of energy extracted or captured directly from natural resources. Primary energy can be
further divided into two distinctive groups:
Renewable (solar, wind, geothermal, tidal, biomass, etc.)
Non-renewable (fossil fuels: crude oil and its products, coal, natural gas, nuclear, etc.)
• The primary energy content of all fuels is generally expressed in terms of toe (tonne of oil equivalent)
One tonne of oil equivalent (toe) = 1×107 kcal = 11630 kWh = 41868 MJ

3. • Primary energy sources are mostly converted in industrial utilities into secondary energy sources; for example coal, oil
or gas converted into steam and electricity.
• Primary energy can also be used directly.
• Primary energy is transformed in energy conversion process to more convenient forms of energy such as electricity,
steam etc. These forms of energy are called secondary energy.
Fig. 1 Major primary and secondary energy sources

4. Commercial and non commercial energy:
Energy that is available in the market for a definite price is known as commercial energy. No matter what the
method of energy production is, whether it is from fossil fuels, nuclear or renewable sources, any form of energy
used for commercial purpose constitutes commercial energy. Example of commercial energy are electricity, coal,
refined petroleum products and natural gas.
Any kind of energy which is sourced within a community and its surrounding area, and which is not normally traded
in the commercial market is termed as non-commercial energy. Non-commercial energy sources include fuels such
as firewood, cattle dung and agricultural wastes, which are traditionally gathered, and used mostly in rural
households.

5. Renewable and non-renewable energy
Renewable energy is the energy obtained from natural sources which are essentially
inexhaustible. Examples of renewable resources include wind power, solar power, geothermal
energy, tidal energy etc.. The most important feature or renewable energy is that it can be
harnessed without the release of harmful pollutants.
A non-renewable resources is a natural resources which can not be produced, grown,
replenished, or used on a scale which can sustain its consumption rate. These resources often
exist in a fixed amount, or are consumed much faster than nature can create them. Examples:
Coal, Oil, Natural gas etc.

6. Fig. 3 Formation of coal
Fig. 4 Petroleum Distillation Refinery

7. Power generation, transmission & distribution
Power generation is the process of generating electric power from other sources of primary energy. The fundamental
principles of power generation were discovered during the 1820s and early 1830s by the British scientist Michael
Faraday. His basic method is still used today: power is generated by the movement of a loop of wire, or disc of copper
between the poles of a magnet.
Methods of generating electricity:
Static electricity, from the physical separation and transport of charge (examples: turboelectric effect and lightning).
Electromagnetic induction, where an electrical generator, dynamo or alternator transforms kinetic energy (energy of
motion) into electricity. This is the most used form for generating electricity and is based on Faraday's law. It can be
experimented by simply rotating a magnet within closed loops of a conducting material (e.g. copper wire).
Electrochemistry, the direct transformation of chemical energy into electricity, as in a battery, fuel cell or nerve
impulse
Photovoltaic effect, the transformation of light into electrical energy, as in solar cells.
Thermoelectric effect, the direct conversion of temperature differences to electricity, as in thermocouples,
thermopiles, and thermionic converters
Nuclear transformation, the creation and acceleration of charged particles (examples: beta voltaic or alpha particle
emission)

8. Power transmission:
Power transmission is the movement of energy from its place of generation to a location where it is applied to
performing useful work.
Power distribution:
An electric power distribution system is the final stage in the delivery of electric power; it carries electricity
from the transmission system to individual consumers.

9. AN OVERVIEW OF POWER PLANT
A power plant is assembly of systems or subsystems to generate electricity, i.e., power with economy and
requirements. The power plant itself must be useful economically and environmental friendly to the society.
Types of Power plant: Power plants are mainly two types:
Conventional
Steam Engines Power Plants, Steam Turbine Power Plants, Diesel Power Plants, Gas Turbine Power Plants,
Hydro-Electric Power Plants, Nuclear Power Plants.
Non-conventional
Thermoelectric Generator, Thermionic generator, Fuel-cells Power Plants, Photovoltaic solar cells Power
System, MHD Power Plants, Fussion Reactor NPP Power System, Biogas, Biomass Energy Power system,
Geothermal Energy, Wind Energy Power System, Ocean Thermal energy conversion (OTEC), Wave and Tidal
Wave, Energy Plantation Scheme.

10. PRESENT STRUCTURE OF POWER SECTOR
Present structure for power generation, transmission & distribution:
Present structure of Power sector can be described by below:
Apex Institution:
1. Power Division, 2. Ministry of Power, 3. Energy & Mineral Resources (MPEMR)
Regulator:
Bangladesh Energy Regulatory Commission (BERC)
Generation:
1. Bangladesh Power Development Board (BPDB), 2. Ashuganj Power Station Company Ltd. (APSCL), 3. Electricity
Generation Company of Bangladesh (EGCB), 4. North West Power Generation Company Ltd. (NWPGCL), 5. Independent
Power Producers (IPPs)
Transmission:
Power Grid Company of Bangladesh Ltd (PGCB)
Distribution:
1. Bangladesh Power Development Board (BPDB), 2. Dhaka Power Distribution Company (DPDC), 3. Dhaka Electric
Supply Company Ltd (DESCO), 4. West Zone Power Distribution Company (WZPDC) Rural Electrification Board (REB)

11. PRESENT POWER SITUATION OF BANGLADESH
Bangladesh Power Sector at a Glance:
Generation Capacity : 27,834 MW
Highest Generation : 16,648 MW (19 April, 2023)
Total Consumers : 44.5 Million
Grid Sub-station Capacity (MVA): 58,076
Distribution Line : 6,29,000 km
Distribution Loss : 7.74% (June 2022)
Per Capita Generation : 608.76 KWh
Access to Electricity : 100%