Managing Power Factors

1
Managing Power Factors
2
What We Will Discuss

• What is power factor?
• Why are higher power factors best?
• How is power factor improved/corrected?
• What is TXU Electric doing about power factor?
• Why is TXU Electric implementing the power factor
  provision in the tariff?
  
• How will this affect your customer?
• When will it start?

3
What is power factor?

• Analogy the ratio of the number of people on the
  freeway to the number of vehicle seats.
  
• Apparent load vehicle seats.
• Real load people.
• Ideal situation all seats full, seating factor
  1.0.

4
What is power factor?

• Real power measured in kW.
• Apparent power measured in kVA.
• Power factor - the ratio of real power divided by
  apparent power.
  
• Ideal power factor 1.0.

5
Why are higher power factors best?

• For the transportation system analogy
• Better utilization of the transportation system.
  (lower loadings)
  
• More stable, problem-free system. (less
  bottlenecks)
  
• More real load can be transported along a given
  corridor. (less need for additional lanes)

6
Why are higher power factors best?

• Similarly, for the electric power system
• Better utilization of the transmission and
  distribution system. (lower loadings)
  
• More stable, problem-free system. (less
  bottlenecks)
  
• More real power can be transported along a given
  corridor. (less need for additional lines)

7
Why are higher power factors best?

• For the transportation system analogy
• Improved energy efficiency.
• Less idling.
• Fewer stops/starts.
• Improved performance.
• Improved safety.

8
Why are higher power factors best?

• For the electric power system
• Improved energy efficiency.
• Customers use less energy.
• Transmission distribution systems have lower
  energy losses.
  
• Improved system stability.

9
How is power factor improved/corrected?

• For the transportation system analogy
• Equipment selection. (Yugo vs. Hummer)
• Buses, HOV lanes, etc. are used to improve the
  seating ratio.
  
• Most are needed/active during peak times.
• A few are needed 24/7.

10
How is power factor improved/corrected?

• For the electric power system
• Equipment selection. (high power factor
  equipment)
  
• Capacitors and other devices.
• Capacitors on the td system are analogous to
  buses on the freeways.
  
• Most are needed during peak times.
• A few are needed 24/7.

11
What is TXU Electric doing about power factor?

• Higher ERCOT guidelines.
• Expansion and aggressive management of capacitor
  fleet.
  
• Tariff feature to adjust billing demand.

12
Why implement the power factor adjustment
provision?

• Higher system power factors required.
• Increasing number of capacitors on-line alone is
  not the best solution.
  
• Encourage higher power factors.

13
How will this affect your customer?

• Residential not directly impacted.
• Demand customer may have higher TDSP charges
  until power factor is corrected.
  
• Customer incentive to install capacitors or other
  corrective devices. (many will have attractive
  economics)

14
How will this affect your customer?

• Example, Customer ABC
• demand 500 kW PF .926 adj. demand
  500(.95/.926) 513 kW.
  
• PF of .926 2.6 demand adjustment.
• Example, Customer XYZ
• demand 1000 kW PF .90 adj. demand
  1000(.95/.90) 1056 kW.
  
• PF of .900 5.6 demand adjustment.

15
When will it start?

• Billing demands adjusted for premises with
  measured power factors beginning 2Q, 2002.
  
• New demand meters to measure power factor
  beginning in 2002.
  
• Existing premises to have measured power factors
  by 1Q, 2006, largest first.