power system planning

1. Module-01 Unit-01
Power System

2. 1.1 Power system
❑1st electrification was in Darjeeling with installation of
small hydro power plant (130kW)(1897). 1344 MW (1947)
Now 344GW.
❑Planning of power system fit with overall energy policy
w.r.t. public opinion +reliability of power supply.
❑Future electricity supply peoples’ expectations,
technological development and availabilities of resource.
❑Duty of Central Electricity Authority(CEA) to adopt
systematic approach to formulate policy and optimise
resource .

3.  Bulk Power Supply
Main generation and Transmission
 Delivery of Power
Distributed Generations, transmission and distribution

4. Electric Power System
Natural Resources – coal, oil and natural gas
Nuclear Power - Nuclear Fission
Hydro Power
Geothermal , Solar, Wind , Bio-mass…..

5. 1.1 Power system
• Planning should consider needs of system.
• Environmental and resource constraints are
demanding for planned and researched projects
Major goals for future are to develop
1. Least cost projects
2. New primary resources
3. Better means of T & D
4. DSM
5. Storage of electricity
• Planning should identify the project with
precision and clarity.

6. Power System Planning
Must fit with overall energy policy , reliability and due respect to public
opinion.

7. 1.1 Power system
Power Industry Structure (Electricity Act 2003)
1. Deregulation
2. Privatisation and vertical disaggregation
3. Wheeling non utility generation
4. Open access

8. Central Electricity Authority CEA
Formulating plans for EPS – cross border transmission system with neighboring
countries
Frame National Electricity Plan (5 years once) – revise in accordance with NPP.
 Ministry of New and Renewable Resources
 Rural Electrification Corporation of India
 National Mission for Solar Power and National Mission for Enhancement of
Energy Efficiency
Funded Schemes:
1. APDRP – Restructured Accelerated Power Development and Reform
2. DDUGJY – Deen Dayal Upadhyaya Gram Jyothi Yojana
3. RGGVY – Rajiv Gandhi Rural Electrification Plan
4. PFC – Power Finance Corporation
5. REC – Rural Electrification Corporation Limited

9. Active and Reactive Power
DC Device – real Power
AC Device – P and Q

10. 1.2 Planning Principles
Generating capacity
to be added
Optimum size of
gen. units
Combination of
gen. types
Environmental
impact of gen.
alternatives
Size of
interconnections
Economical voltage
levels & type of lines
Facility addition
and financial
structure
Targets of new
technology
Energy conservation
and load management
Reliability of
supply
Points to be explored :

11. 1.2 Planning Principles
1. G = C + L
Where:
- G represents the total generation at any moment,
- C represents the total electricity consumption, and
- L represents the losses on the system including transmission and
distribution.
2. To reach consumers , electricity must travel through large kms
3. Economic power transfer at high voltage
4. Network – nodes and connections
5. Swing occurs by nodal mismatch between external power injection vs
absorption by network
6. Electricity travels at very high speed

12. Planning Principles (Cont)
7. Power Grid Electricity moves by displacement
8. Reserve capacity in generation and transmission
9. Loss in transmission power
10.Parallel Path flows
11.Location Matters
12.Community power and self power generations
13.Network Planning
14. Static Power flow
15. Planning standards – Adequacy and Security
16 . Smart Power System

13. 1.3 Planning process
• Process of taking careful decision.
• Process of selecting vision, values, mission and objectives, decide
plan to achieve them.
• Input for planning is quality of systematic thought that goes
into decision.
• Process of establishing power industry is time consuming and
capital intensive.
• Planning saves project time and utilizes resource economically
• Planning should consider
1.uncertinity about future
2. alternative action choices
3. goals and constraints

14. 1.3 Planning process
It consists of three cyclical components
1. Learning about the environment related issues and possible future
scenarios to identify :
a. Strategically goals
b. Decision criteria and constraints
c. Technological needs and opportunities.
2. Thinking about existing plans, associated costs and risks.
This involves
a. Investment of resources
b. Unforeseen factors
c. Reliability of outcome
3. Preferred plans based on support analysis

15. 1.3 Planning Components
(figure 1.1)

16. 1.3 Planning process
Characteristics of power system that makes planning challenging
1. High capital intensive
2. Plan implemented in advanced countries cannot be implemented in developing
countries
3. Planning diverges a lot before it actually converges.(Eg: Environmental effects)
Planning Actions
Planning
Implementation
of plans
Monitoring,
comparing plans
with results
Corrective
action
New plans
No undesirable
deviation from plans
Undesirable
Deviation

17. 1.3 Planning Levels
Function Time Frame(Years) Organizational Level
Perspective 10-20 Corporate vision ,
mission, values,
national/state power
policy
Strategic 5-10 Power utility level,
regional ,national level
Tactical 1-5 Power utility
Operational 0-1 Power utility

18. Long Term Strategy
1.Directions for capacity augmentation
2.Environmental issues
3.Water source development – inter state/regional issues
4.Functional and commercial issues
5.Thermal power development – land and water availability-
fuel supply agreements
6.Re-engineering of power industry

19. Medium Term Strategy
1.Renovation,modernization,upgrading,extension in the
existing power plants
2.Reduction of transmission and distribution losses
3.Construction of shorter gestation power plants – solar PV
,wind, gas turbine based combined cycle.
4.Demand Side Management

20. Short Term Strategy
1.Improving the performance and maximizing the utilisation
2.Installing capacitors at various HV and LV locations
3.Computerised management

21. 1.4 Project Planning
1. Preliminary Investigations
2. Project identification and formulation – desired
needs and feasible report
3. Detailed Report – technical ,demand, organization
and environmental , financial and economic
4. Appraisal of Detailed Feasibility Report

22. 1.4 Project planning
 Detailed Feasibility Report
 Detailed Project Report
 Project Implementation

24. 1.5 Power Development
Economic strength depends on availability of power.
Planning process involves following steps :
• Vision mission and load forecasting.
• System expansion will be done by conducting load flow studies.
• Economical system can be designed by relocating generating
stations and by doing modifications of transmission lines .
• Determine best system configuration and study the system under
fault conditions as a short term plan.
• Finally stability studies for severe fault conditions .
•Planner should have working knowledge of mathematical tools
and software

25. 1.5 Power Development
Plan Time
period
Activity
1. Long-Term planning 5-20 yrs Vision mission load forecasting National grid
and regional system expansion scheme
2. Medium-Term planning 2-5 yrs Generation sector (coal, hydro etc.,) renovation and
modernization of generating plants
3. Short-Term planning 1-2 yrs System improvement of T&D system and also
nonconventional sources of generation
4. Operational planning 15days-
1yr
Maintenance scheduling and fuel requirements
5. Operational planning 1-7
days
Generation scheduling and network switching
6. Operational planning 2-12
hrs
Power purchase or selling and Economic dispatch
instruction
7. Operational planning 0-2 hrs Network switching , economic dispatch control
• Planning activities for power development depends on time duration

26. 1.6 Power growth
1. Power shortages are to be reduced. One of the disturbing feature is
dependence on thermal but plan objective was ratio 60:40 mix of
thermal and non thermal in 1996. In the year 2018 march scenario
was 64.8: 35.2
2. Private sector must be made to participate fully in power sector
development as the power consumption is increasing, power
generation has to be increased.

28. 1.6 Power growth
3. Plant load factor: (average load / peak load) is poor .
poor performance shortage of fuel, shortage of funds,
poor management etc
4. Transmission and distribution is another affecting factor
Improper load management , low construction quality ,
unmetered supply for agriculture , theft of energy

29. 1.7 National and Regional Planning
GRIDS
Northern
Western
Eastern
North-eastern
Southern

30. 1.7 National and Regional Planning
Reasons for grid division :
– Diversity in topography
– Daily Peak variations – at different times of a
day(eg. irrigation)
– Annual peak load – (summer & winter)
– Diversity of Resources in different regions

31. ADVANTAGES OF GRID DIVISION :
– Allows joint planning and operation of facilities
– Exchange of economical energy easier
– Saves money in construction of facilities in isolated
areas.
– Increases reliability
– Offers distinct economic and non-coincidental
occurrence of peaks of the participating systems.
– reduction in total generation and reserved capacity
1.7 National and Regional Planning

32. 1.7 National and Regional Planning
DISADVANTAGES :
– Coordination among utilities w.r.t tariff and units
– Regulatory provisions

33. 1. Integrated Resource Planning
2. Least Cost Utility Planning

34. 1.7 National and Regional Planning
INTEGRATED RESOURCE PLANNING
⮚Utilities have to evaluate all supply side & demand side options.
1.Supply side options :
a) Better technology
• conventional plants combustion turbines ,low emission
• clean coal , Flue gas desulphurization etc.
b) Increasing role of renewables
• broaden the scope of non-conventional sources
c) Increasing availability of generating stations
d) Efficient operation of regional and national grid
e) Strengthening of existing T & D systems ( by adding new links
& capacitor banks) to reduce loss and improve voltage profiles

35. 1.7 National and Regional Planning
INTEGRATED RESOURCE PLANNING
2. Demand side options :
a) Taking energy conservation methods
b) Maintaining consumer PF should be made mandatory (not
less than 0.95 lagging)
c) Load management /staggering
– improving generating stations load factor
d) Time of day tariff – peak / night / other time
e) Captive power generation
f) Checking pilferage

36. LEAST COST UTILITY PLANNING
Short comings of traditional planning are:
✔ Demand forecasting and investment planning are considered sequential instead of
interdependent
✔ Resource planning is inefficient (shortage of resources)
Least cost utility planning :
✔ Is to provide reliable electrical services at the lowest cost.
✔ Apply supply and demand side resource management
✔ Plant rehabilitation
✔ conventional centralized generation sources
✔ Decentralized power generation-non conventional sources
✔ T & D options
✔ Loss reduction programmes
✔ Load management
✔ End use efficiency
✔ Alternative tariff options
1.7 National and Regional Planning

37. 1.7 National and Regional Planning
LEAST COST UTILITY PLANNING
Merits : Benefits consumers and suppliers
– Affordable acquisition of resources
– Low in cost
– Environmentally benign
– Acceptable to public
– Reduced risk faced by utilities.
System expansion detailed project reports (DPRs) must be
based on least cost planning and need to be made mandatory
by amending the Electricity (Supply) Act, 1948.

38. 1.7 National and Regional Planning
LEAST COST UTILITY PLANNING
The logic for least-cost planning
LEAST COST
PLANNING PROCESS
Options
(plans)
Regulations
Attributes

39. 1.7 National and Regional Planning
Process of least cost planning
LEAST COST UTILITY PLANNING

40. 1.7 National and Regional Planning
LEAST COST UTILITY PLANNING
Evaluation :
– All options should be assessed in a consistent manner
for a full cycle
– Once initial evaluation is complete, environmental ,
economic factors should be studied – avoids loosing
out on options with high impact
– Non cost factors should be evaluated – variability of
factors, alternative solutions based on factor variation

41. 1.7 National and Regional Planning
LEAST COST UTILITY PLANNING
Investments on power systems :
– Capital cost
– Interest on capital
– Fuel cost
– Operational and maintenance cost – loss dependent

42. 1.8 Enterprise Resources Planning
Integrated information system Smooth operation of system
various resources
(Man, material, machine….)
Efficient and dynamic organization

43. 1.8 Enterprise Resources Planning
• Integration of functional and geographically dispersed
regions/sub-stations through cross-functional, process-oriented
and virtually integrated enterprise.
• All location ERP data centre ( Gurgon and
Yelahanka)
• Connectivity is given by telecom department
• Currently 43 locations are connected

45. 1.9 Structure of a Power System

46. 1.9 Structure of a Power System

47. 1.9 Structure of a Power System
The basic system consists of energy resources such as hydro, coal, gas etc.,
a prime mover, a generator and a load.
Some sort of control system is required for supervising it.
The prime mover may be a steam driven turbine, a hydraulic turbine or an
internal combustion engine.
prime movers :energy in the form of heat, falling water or fuel
into rotation of the shaft
drives the generator.

48. 1.9 Structure of a Power System
generator may be alternator or a d.c. machine.
Electrical load on the generator may be lights, motors, heat or other devices
The control system functions: a) to keep the speed of the machine constant
b) the voltage within prescribed limits
c)excitation within the generator capability.
The active power (MW) is regulated by frequency (speed) control
The reactive power (MVAr) and voltage is regulated by excitation control.

49. 1.9 Structure of a Power System
Power system components

50. 1.9 Structure of a Power System
Single line diagram

51. 1.9 Structure of a Power System
The power transmission and
distribution network may be of
the following types
1. radial system :
lines form a 'tree' spreading out
from the generator.
Opening any line results in
interruption of power to one or
more of the loads.

52. 1.9 Structure of a Power System
2. loop system :
all loads will continue to be served even if
one line section' is put out of service.
In normal operation the loop may be open
at some point at A as shown in the figure.
In case a line section is to be taken out, the
loop is first closed at A
the line section is put on shut down.
In this way no service interruption
occurs.

53. 1.9 Structure of a Power System
3. Network of line
the same loads being served by a network.
arrangement has a higher reliability as each load
has two or more circuits of supply
The sub transmission and distribution circuits
are commonly designed as radial or loop circuits.
The high voltage transmission lines are generally
laid as interconnected or networks.
Transmission and distribution are distinguished by
their voltage levels.
general, transmission systems have bulk power
handling capability, and relatively long lines .
connecting generating stations to load centers of
the utilities.

54. 1.10 Power Resources
• India is third in primary energy consumption
•Wind is the largest renewable source in India

55. 1.10 Power Resources
National resources
1. Renewable resources : India is the 7th largest producer
of hydroelectric power, 4th largest of wind power (TN)
2. Coal resources :India is forth largest in coal production
3. Gas and oil resources :82 % import to be reduced to 67%
by 2022
4. Nuclear resources : 22 nuclear reactors in 7 nuclear stations
(Eg: Kaiga has 4 reactors operational 2 are planned )

56. 1.11 Planning tools
Aim :
– To supply power – reliable, minimum cost, flexibility for expansion
Criteria and constraints :
– Reliability
– Environment
– Economics
– Electricity pricing
– Financial constraints
– Society impacts
– Value of electricity
Criteria's conflict each other making planning complex

57. 1.11 Planning tools
Available tools : (3 basic techniques)
– Simulation tools : Simulate the behavior of power system under certain
conditions
• Load flow generation reliability
• Short circuit studies generation cost
• Fault studies risk analysis
• Transient studies optimum generation mix
• Harmonic studies dynamic studies
• Production costing studies sub synchronous osc.
• Estimation of envr impact system reliability eval.
– Optimization tools : Minimize / maximize an objective function
• Optimum power
• Least cost expansion
• Generation expansion planning

58. 1.11 Planning tools
– Scenario techniques :
• A description of probable or possible sequence of events is
developed.
• The events are recorded into a case history & a database is
build.
• All possible outcomes are investigated
• Done by state electricity boards, research organizations
Utilities should prepare integrated resource plans
The long term plans seek to develop the best mix of demand and
supply option to meet consumer needs for energy .

59. 1.12 Power Planning Organization

60. 1.12 Power Planning Organization
Functions of planning organization
1. Vision mission and value statement
2. Practical proposal set up to implement these
3. Decide the preferred mode of development
4. Communicate the decisions to design, construction and finance
department , ensure developments are executed as per the plan.
5. Demand forecasts, generating plant , transmission and distribution
requirements should be mentioned in guides and manuals

61. 1.12 Power Planning Organization
Organization models
Different functions of electricity supply : G, T , D and C
1.Vertically integrated model : mostly used in India
2. Integrated model : IPP and NUG(Europe )
3. Open access model: long term basis, wheeling
(no direct dealings with consumer) (USA)
4. Spot market model : short term (generators and consumers can
deal directly with each other) (UK)
5. Decentralized generator model

62. 1.12 Power Planning Organization
Organization models

63. 1.12 Power Planning Organization
Organization models

64. 1.12 Power Planning Organization
Reasons to have different models
1. To lower electricity costs
2. To guarantee security and quality of power supply
3. To seek private investment
4. To limit environmental consequences
5. To contribute for social and political objectives