Distributed Generation
SUBMITTED TO:Mr.inderpreet Singh
SUBMITTED BY:Mr. Naresh Chand
UIDNO-13MEL1007
Introduction
 Distributed generation in simple term can be
defined as a small-scale generation. It is active
power generating unit that is connected at
distribution level.
 IEEE defines the generation of electricity by
facilities
sufficiently smaller than central plants,
so as to allow interconnection at nearly any point
in the power system, as Distributed Resources.
 Electric Power Research Institute (EPRI) defines
distributed generation as generation from a few
kilowatts up to 50 MW.
 Distributed generation, also called on-site
generation, distributed energy or district
 Most countries generate electricity in large
centralized facilities, such as fossil fuel (coal, gas
powered), nuclear, large solar power plants or
hydropower plants. These plants have excellent
economies of scale, but usually transmit electricity
long distances and can negatively affect the
environment.
 Distributed generation allows collection of energy
from many sources and may give lower
environmental impacts and improved security of
supply.
 Distributed generation reduces the amount of
energy lost in transmitting electricity because the
electricity is generated very near where it is used,
How Distributed Generation
Works=?
 DG as generation that is not centrally planned,
centrally dispatched at present, usually
connected to the distribution network, and
smaller than 50-100 MW.
 These generators are distributed throughout the
power system closer to the loads as shown in the
previous slide.
 The DG penetration in the grid poses new
challenges and problems to the network
operators as these can have a significant impact
on the system and equipment operations in
terms of reliability, power quality, stability and
safety for both customers and electricity supplier.
Types of Distributed Energy
Resources
Cogeneration:-Distributed cogeneration sources
use steam turbines, natural gas-fired fuel cells,
micro turbines or reciprocating engines to turn
generators. The hot exhaust is then used for
space or water heating, or to drive an absorptive
chiller for cooling such as air-conditioning.
Vehicle-to-grid:-Future generations of electric
vehicles may have the ability to deliver power
from the battery in a vehicle-to-grid into the grid
when needed. An electric vehicle network could
also be an important distributed generation
resource.
Solar panel
Solar panel:-Popular sources of power for
distributed
generation are solar heat collection
panels and solar panels on the roofs of buildings or
free-standing. Solar heating panels are used mostly
for heating water and when the water is heated into
steam it can effectively and economically used in
steam turbines to produce electricity.
Wind turbine
Wind turbine:-Another source is small wind
turbines. These have low maintenance, and low
pollution, however as with solar, wind energy is
intermittent. Construction costs are higher than
large power plants, except in very windy areas.
Waste-to-energy:- Municipal solid waste (MSW)
and natural waste, such as sewage sludge, food
waste and animal manure will decompose and
discharge methane-containing gas that can be
collected as used as fuel in gas turbines or micro
turbines to produce electricity as a distributed
energy resource.
Cost factors:- Co generators are also more
expensive per watt than central generators. They
find favor because most buildings already burn
fuels, and the cogeneration can extract more
value from the fuel. Local production has no
electricity transportation losses on long distance
power lines or energy losses from the Joule
Modes of Power
Generation
DER
systems may include the following
technologies: Combined heat power (CHP)
 Fuel cells
 Micro combined heat and power (Micro CHP)
 Micro turbines
 Photovoltaic Systems
 Reciprocating engines
 Small Wind power systems
 Tri generation
Power Quality Issues:-
A major issue related to interconnection of
distributed resources onto the power grid is the
potential impacts on the quality of power
provided to other customers connected to the
grid.
Voltage Regulation:-Over-voltages due to
reverse power flow: If the downstream DG output
exceeds the downstream feeder load, there is an
increase in feeder voltage with increasing
distance. If the substation end voltage is held to
near the maximum allowable value, voltages
downstream on the feeder can exceed the
acceptable range.
DG Grounding Issue:-A grid-connected DG,
whether directly or through a transformer, should
provide an effective ground to prevent un-faulted
phases from over-voltage during a single-phase
to ground fault. Proper grounding analysis of DG
will ensure compatibility with grounding for both
the primary and secondary power systems.
Harmonic Distortion:-Voltage harmonics are
virtually always present on the utility grid.
Nonlinear loads, power electronic loads effects of
the harmonics include overheating and
equipment failure, faulty operation of protective
devices, nuisance tripping of a sensitive load and
interference with communication circuits’
Islanding:-“Islanding” occurs when a small
region of the power grid is isolated by broken
lines, etc., and yet local sources provide enough
power to keep the voltages up
 In case the DG in the distribution system is
capable to meet the load demand, DG can be
operated in the island mode and continue to
From
Utility
energize
the distribution system.
Plant
Island of “hot” lines
LINE BREAK
Transformer
070412
Generator
Direct use
Generation:-
of
Distributed
 Photovoltaic (PV), wind, micro-combined heat &
power (CHP) and many others produce power
locally for direct use, reducing the need for
transporting the energy across transmission and
distribution grids.
Advantages & Disadvantages
 Distributed generation reduces the amount of
energy lost in transmitting electricity because
the electricity is generated very near where it
is used, perhaps even in the same building.
This also reduces the size and number of
power lines that must be constructed.
 Disadvantages of DG
 Power Quality
 Cost of Operation and Maintenance
 Long Term Reliability of the Units
 Interconnection
Conclusion
 The distributed generation help us to reduce the
cost of the transmission line and the transmission
losses .distributed generation playing important
role in the field of the electricity generation
whereas Different issues related to power quality
when DR is integrated with the existing power
system has been discussed in the report .It can
be concluded from this discussion that when
interconnecting DR to the power system, these
issues must be considered which could affect
power quality and safety. Penetration of DR can
be successfully integrated with the power system
as long as the interconnection designs meet the
References:-
1.
www.clarke-energy.com, retrieved 16
September 2013
2.http://www.forbes.com/sites/peterdetwiler/201
2/12/26/solar-grid-parity-comes-to-spain/
3.http://oilprice.com/Latest-Energy-News/WorldNews/Spain-Achieves-Grid-Parity-for-SolarPower .html
4.Boyle, Godfrey. Renewable Energy, Second
Edition.
Oxford: Oxford University Press,
2004, ISBN 0-19-26178-4. (my preferred text)
5.http://www.forbes.com/sites/peter
detwiler/2012/12/26/solar-grid-parity-comes-tospain
THANK YOU