Microturbines are small combustion turbines approximately the size of a refrigerator that can generate 25-500 kW of electricity. They provide both electricity and thermal energy for heating and cooling. Microturbines are commercially available and use natural gas, hydrogen, propane or diesel as fuel. They have efficiencies of 20-30% and produce low NOx emissions. Microturbines offer distributed energy generation by producing power on-site, which eliminates transmission losses and enables combined heat and power applications. Their advantages include compact size, long maintenance intervals, low emissions and high efficiency compared to other distributed generation technologies.

1. MICROTURBINE
PRESENTED BY-
ISTIAK AHMED TUHAM (112411)
SYED RAIHAN HOSSAIN (112421)
MD. ABRAR AMIN (112423)
1

2. Introduction
 MicroTurbines are new type of
combustion turbine used for
stationary energy generation.
 The concept is evolved from
automotive and truck turbochargers,
auxiliary power units (APU) for
airplanes.
 Approximately the size of a
refrigerator with outputs of 25 kW to
500 kW.
 They provide not only electricity , but
also the thermal energy to provide for
all heating and cooling needs
2

3. MicroTurbine producing power, as well as heat
3

4. Microturbine Overview
 Commercially Available Yes (Limited)
 Size Range 25-500 kW
 Fuel Natural gas, hydrogen, propane,
diesel
 Efficiency 20-30% (Recuperated)
 Environmental Low (<9-50 ppm) NOx
 Other Features Cogeneration (50-80°C water)
 Commercial Status Small volume production,
commercial prototypes now.
(Courtesy of California Distributed Energy Resources Guide on
Microturbines)
4

5. Components of Microturbine
 Turbo Compressor
 Combustor
 Generator
 Recuperator (Internal Heat Exchanger)
 Turbine
 Power Electronics (Rectifier & Inverter)
5

6. Combined Heat & Power (CHP) Diagram 6

7. Working Principle
 Microturbines are small gas turbines, most of which feature an
internal heat exchanger called a recuperator.
 In a microturbine, a radial flow (centrifugal) compressor compresses
the inlet air that is then preheated in the recuperator using heat
from the turbine exhaust.
 Next, the heated air from the recuperator mixes with fuel in the
combustor and hot combustion gas expands through the expansion
and power turbines. The expansion turbine turns the compressor
and, in single-shaft models, turns the generator as well.
 Finally, the recuperator uses the exhaust of the power turbine to
preheat the air from the compressor.
 Single-shaft models generally operate at speeds over 60,000
revolutions per minute (rpm) and the permanent magnet generator
generates electrical power of high frequency, and of variable
frequency (alternating current --AC). This power is rectified to direct
current (DC) and then inverted to 50/60 Hz for commercial use.
7

8. How a Microturbine works
8
Turbine rotates the
generator at high RPM which
produces electricity of high
frequency

9. Types of Microturbine
Unrecuperated Microturbine
(Simple cycle)
Recuperated Microturbine
9

10. Recuperated Microturbine 10

11. Comparision
Unrecuperated
 Compressed air is mixed
with fuel and burned
under constant pressure
conditions.
 Efficiency 15%.
Recuperated
 A sheet metal heat
exchanger (recuperator)
recovers temperature of the
air stream supplied to the
combustor.
 Efficiency 20~30%.
11

12. Distributed Energy Generation
 Energy produced in thermal and hydro electric
power plants is distributed to the users through
network of line (transmission & distribution) called
the power grid.
 Any technology of getting electric energy other
than power grid, directly at the distribution level, is
called Distributed Energy Generation.
 In IUT, when load-shedding occurs, IUT generator
serves as distributed energy source.
 Example: Microturbine, Diesel Generator (Backup
generator), Solar Panel etc.
12

13. Advantages of Distributed Generation
 The losses during power transmission are
eliminated.
 The combined heat and power (CHP)
technology can be applied.
 Low emission and operating cost.
 High efficiency.
13

14. Advantages of Microturbine
 Small number of moving parts
 Compact size
 Lightweight
 Good efficiencies in cogeneration
 Low emission
 Can utilize waste fuels
 Long maintenance interval
 No vibration
 Less noise than reciprocating engines
14

15. Economics 15

16. Microturbine Manufacturers
 Bowman power systems
 Capstone Turbine Cooperation
 Elliott energy systems
 Turbec AB
 Ingersoll-Rand Company
16

17. 17