Economics of Power Utilization - 10th Batch
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Transcript of Economics of Power Utilization - 10th Batch
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8/3/2019 Economics of Power Utilization - 10th Batch
1/19
EE 2802 Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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Cost of electric power
Tariffs
Factors influencing the costs and tariffs
Energy demand management
Power factor correction
2EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
3/19
Cost of electricity includes all the initial andcontinuousoperation costs
Alls
ho
uld be co
ns
idered befo
ref
ixing tariff
for consumers
Fixed costs
Running / operating costs
3EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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FIXED COSTS OPERATING COSTS
Interest on capital
investment Allowance for
depreciation
Taxes and insurance
Most of the salaries
Small portion of thefuel cost
Most of the fuel cost
Small portion ofsalaries
Repair andmaintenance
4EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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1. Fixed charge
For the portion of the plant that has beenallocated for the customer
2. Variable charge / Unit charge
For the units used by the customer (per kWh)
3. Maximum demand charge
Charge for the maximum demand (per kVA)
5EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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Domestic purpose
Religious purpose
Industrial purpose
Hotel purpose
General purpose
6EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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Fixed Charge(Rs/month)
Unit Charge(Rs/kWh)
Up to30 units 30.00 3.00
30 ~ 60 units 60.00 4.70
60 ~ 90 units 90.00 7.50
90 ~ 120 units 315.00 21.00
120 ~ 180 units 315.00 24.00
Above 180 units 315.00 36.00
7EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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FixedCharge
(Rs/month)
UnitCharge
(Rs/kWh)
Demand Charge(Rs/kVA/month)
Industrial I1 240.00 10.50
Industrial I2 3000.00 850.00Peak 13.50
Off peak 7.35
Day 10.45
Industrial I3 3000.00 750.00
Peak 13.40
Off peak 7.15
Day 10.258EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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1. Demand
2. Diversity of demand
Maximum demand of various consumersnot occur simultaneously
This result in lower cost of electric energy
9EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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3. Load factor
System is designed for maximum demand
Fully occupied or not, there are fixed charges
Poor load factor -> charge per kWh is high
To improve load factor -> accept off-peakloads at lower rates
10EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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4. Power Factor
Productive power consumed on resistive loads
Non-productive power consumed oninductive loads
Low power factor -> greater non-productivepower
11EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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Following information can be obtained
Daily operating schedule
Maximum lo
ad Size of generator units required
etc
12EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
13/19
GENERATIONTRANSMISSION &
DISTRIBUTION
Plant loadfact
orimprovement
Clean fuel
Renewable
energy
Efficient
transfo
rmers
Transformerright sizing
END USE
Approaches
to
impro
veprocessefficiency
Efficient
appliances
Tariffregulations
13EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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Customerbenefits
Societal benefits Utility benefits
Satisfy electricitydemands
Reduceenvironment
degradation
Lower cost ofservice
Reduce costs Conserveresources
Improveoperatingefficiency
Improve value ofservice
Protect globalenvironment
Reduce capitalneeds
Improve lifestyleand productivity
Maximizecustomer welfare
Improve customerservice
EE2802 - Applied Electricity 14
Benefits ???
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8/3/2019 Economics of Power Utilization - 10th Batch
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Power factor of all AC motors &transformers is < 1
Majority of induction motors are inductionmotors
High p.f. at full load
Low p.f. at light loads
For a 3-phase balanced system
Low p.f. -> high current
15EE2802 - Applied Electricity
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8/3/2019 Economics of Power Utilization - 10th Batch
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Disadvantages of low power factor
Line losses (I2R) are high
Large equipments are required
high capital cost
Large voltage drop
need extra regulation equipment
Low efficiency
EE2802 - Applied Electricity 16
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How to improve?
Inject a leading current into the circuit.
1. Installation of static capacitors
Capacitor may result in over correction
Toovercome automatic correction(control the no.of capacitors)
EE2802 - Applied Electricity 17
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8/3/2019 Economics of Power Utilization - 10th Batch
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How to improve?
Inject a leading current into the circuit.
2. Installation of synchronous motors
Employ instead of induction motors
Or use only for p.f. correction
3. Phase Advancers
Method of manipulating the phasecurrent
EE2802 - Applied Electricity 18
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8/3/2019 Economics of Power Utilization - 10th Batch
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EE2802 - Applied Electricity 19