Conservation Voltage Reduction (CVR) for Electric Distribution Cooperatives

Transcription

1 Conservation (CVR) for Electric Distribution Cooperatives Rob Ardis, PE COO, Pee Dee Electric Cooperative Bob Uluski, PE Utility Integration Solutions (UISOL)

2 Volt-VAR Control Not a New Concept Maintain acceptable voltage and power factor ANSI Voltage Standard Service Delivery Voltage Service Delivery Voltage 126V 120V 114V

3 What is Conservation? Practice of maintaining lower, but acceptable voltage ANSI Voltage Standard Service Delivery Voltage Service Delivery Voltage 126V 120V 114V

4 Conservation Why Do It? Most electrical devices operate more efficiently with reduced voltage Power = V 2 R Slope of line is load-to-voltage sensitivity Aka: CVR Factor

5 CVR Factors for Common Appliances Incandescant Old AC Units CFL Refrigeration Freezer Pool Pumps and Filters Heat pumps Hot Tubs and Spas Furnace Fans New AC Units Water Heating Dishwasher Clothes Dryer LED Lighting Television Personal Computers Constant Power Devices Using CVR to Reduce Peak Load

6 Impact of on Electric Motors Myth: Voltage reduction does not reduce electricity consumption Constant Power Device??

7 Impact of on Electric Motors Fact: Voltage reduction does not reduce electricity consumption Not Constant for small Voltage reduction Volts Volts

8 Two Variations of Conservation practice of reducing voltage whenever possible Peak practice of reducing voltage only during peak load

9 Coincident Peak Billing Demand Savings using Conservation Rob Ardis, PE COO, Pee Dee Electric Cooperative

10 CVR versus VVO Volt-VAR Optimization main purpose is to reduce generation and fuel requirements by reducing system losses on a large scale 1. Use voltage regulation to start at a lower (compared to tradition) voltage and maintain that level. This reduces kwh and kvarh delivery. 2. Use capacitors to further reduce kvarh delivery requirements. 3. This combination (1 and 2) reduces current in system conductors and, therefore, reduces system losses. 4. Also happens to reduce demand when system is peaking. We use CVR to improve our billing load factor. 1. Starting voltage is set at 126V so that voltage at end of line is still tolerable without regulation (normally). Reduces maintenance costs and system weak points. 2. Reduce this voltage at times of likely peaks to lower demand charges.

11 How We Are Billed 12 individual 60-minute coincident peak demands Everyone on rate is held accountable for their contribution when the system was peaking not necessarily their own peak Calendar Month 20 SC Distribution Cooperatives do not generate

12 Demand Charge History

13 Voltage Regulation If it wasn t cost effective before, might be now Need to analyze technical and man-power requirements Must also consider tolerable voltage ranges

14 Specific to PDEC Leaning more toward feeder regulation Very few downline regulators Targets for load control (130 MW) First day of month Temperature in Florence, SC 6-person team (SCADA from Home) Very few capacitors in system Tilt: Shift from negative to positive

15 Historical Peak Hours

16 5500 System Load versus Florence Temperature

17 Day of the Peak

18 Hour of the Peak

19 Typical Winter Morning :00 AM 5:28 AM 5:57 AM 6:26 AM 6:55 AM 7:24 AM 7:52 AM 8:21 AM 8:50 AM 9:19 AM

20 September 8 (3:43-8:00) Real Reactive :00 13:12 14:24 15:36 16:48 18:00 19:12 20:24 21:36 22:48 0:00

21 September 12 (5:44-7:50) Real Reactive :00 13:12 14:24 15:36 16:48 18:00 19:12 20:24 21:36 22:48 0:00

22 September 28 (3:33-7:11) Real Reactive :00 13:12 14:24 15:36 16:48 18:00 19:12 20:24 21:36 22:48 0:00

23 Sample Month Net Savings Estimated Demand Reduced: kw Percent : 2.59% Profit per kwh: 5.3 mills Cost of control per hour: $ Savings during peak: $37,884 Time we were in control: 21 hours Net Savings: $34,412 Last Year: $400k-$500k

24 What s New? Automating the process with converted water heater switches Our newest AMR meters return voltage readings (5257 current count). Two peaks now production and transmission New daily report from our G&T Using CVR to Reduce Peak Load

25 Using CVR to Reduce Peak Load

26 Questions??? Contact Information: Rob Ardis (843) Bob Uluski (215)

27 SUPPORTING MATERIAL Using CVR to Reduce Peak Load

28 Approaches to Volt VAR Control Standalone Field devices perform independent VV Control actions based on local measurements SCADA Rule-based control of field devices based on distribution system measurements and fixed rules Heuristics approach VV control actions based on past experience ( self learning ) and judgment rather than detailed analysis of measurements Advanced Analytics - Field devices controlled based on detailed analysis of measurement data DMS Model-Driven VV control of field devices based on analysis of as operated distribution system model