September 28, Anna Zaklikowski, PE Brian Hemphill, PE. HDR Engineering, Portland, OR

Transcription

1 September 28, 2010 Anna Zaklikowski, PE Brian Hemphill, PE HDR Engineering, Portland, OR

2 1. Micro Hydro- Turbine Tutorial 2. Evaluation Approach for Estimating Annual Energy Recovery 3. Impacts from Variabilities and D/S Flow Control

3 Basic Concept Energy Recovery in Water Distribution Systems Pressure from sources is too high and must be reduced Typically done with pressure reducing valves (PRVs) By using a turbine, part of energy is converted to power Power Output (kw) = (Flow, gpm)(tdh, ft)(0.746 kw/hp)(100)(eff) 3,960

4 Case Study: TVWD Center St. Generator Station Identify energy recovery opportunities Evaluate alternatives for retrofit or replacement of existing turbine Determine annual energy recovery and project payback periods Sustainability evaluation (CO 2 emission offset)

5 Center St. Generator Station

6 TVWD Distribution System Center St. Generator Station

7 Center St. Generator Station Worthington Turbine (112 kw) Generator 14 BFV

8 Evaluation Approach Identify evaluation period and future system changes Develop hourly flow & pressure projections for evaluation period Capture diurnal and seasonal variabilities Future system growth and changes Calculate generator kw for each hour during evaluation period Determine project cost and construction/retrofit feasibility for alternatives Compare alternatives: Determine project payback period (assume $0.05/kWh) Calculate carbon offset for each alternative (1 kwh = 1 lb CO2)

9 Center St. Generator Station - Pressure vs. Flow 50 Generator Station Pressure Drop, psi Existing turbine H/Q (Estimated) Pressure too low to run turbine Center St Data Turbine curve ,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 Net Generator Station Flow & Turbine Flow, gpm

10 Center St. Generator Station - Pressure vs. Flow Generator Station Pressure Drop, psi Available pressure converted to energy Pressure too low to run turbine Bypass needed in this area Center St Data Turbine curve ,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 Net Generator Station Flow & Turbine Flow, gpm

11 Center St. Generator Station - Pressure vs. Flow Flow too low; need PRV to use turbine Generator Station Pressure Drop, psi Available pressure converted to energy Center St Data Turbine curve Pressure too low to run turbine Bypass needed in this area ,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 Net Generator Station Flow & Turbine Flow, gpm

12 Center St. Generator Station - Pressure vs. Flow Generator Station Pressure Drop, psi Center St Data Turbine curve Turbine kw Turbine Power (kw) ,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 0 Net Generator Station Flow & Turbine Flow, gpm

13 Analysis Approach: Center St Generator Station Calculate hourly kw through 2016 Identify and evaluate alternatives: Existing 112 kw turbine (baseline scenario) Existing turbine with D/S PRV Replacement of existing turbine with Cornell 44, 50, 83, and 96 kw turbines (w/ and w/o D/S PRV)

14 Center St. PRV Station Flow and Pressure 25, Generator Station Flow (gpm) Generator Station Pressure Drop (psi) Generator Station kw Summer: High flows; lower pressure 90 20, Generator Station Flow (gpm) 15,000 10, dpressure (psi) Power (kw) 5, J F M A M J J A S O N D Month -

15 Center St. Flow and Pressure Projections Average Pressure Drop Flow (mgd) Average Flow Pressure Drop (psi)

16 Alternative 3: 6TR2 (50kW) Alternative 5: 10TR2 (83kW) Alternative 2: 6TR1 (96kW) Alternative 4: 5TR1A (44kW)

17 Station Pressure Drop (psi) Center St. Turbine Alternatives 0 5,000 10,000 15,000 20,000 25,000 Flow (gpm) Existing Turbine Cornell Turbine 6TR1 Cornell Turbine 6TR2 Cornell Turbine 5TR1A Cornell Turbine 10TR Data 2016 Data

18 Center St. Evaluation Results 2,500 no D/S PRV w/ D/S PRV Energy Recovery (MWh) ,000 1,500 1, ,680 1,390 1,800 1,320 1,760 1,390 1,590 1,290 1, ) Existing Turbine 2) Cornell Turbine 6 TR1 3) Cornell Turbine 6 TR2 4) Cornell Turbine 5 TR1A 5) Cornell Turbine 10 TR2 Flow control D/S of turbine was found have major impact on energy recovery results

19 Center St Generator Station Modeled Generator kw: Existing Turbine (no PRV) Theoretical (Modeled) kw Actual kw Generator Station Flow (gpm) 2007 Energy Recovery: 28,500 kwh (~$1,430) 25,000 20,000 Power (kw) ,000 10,000 5,000 Flow (gpm) 0 J F M A M J J A S O N D Estimated Energy Recovery: 810 MWh (~$40,000 or ~$5,700/yr) 0

20 Center St Generator Station Modeled Generator kw: Existing Turbine (w/prv) Theoretical (Modeled) kw Actual kw Generator Station Flow (gpm) 25,000 20,000 Power (kw) ,000 10,000 5,000 Flow (gpm) 0 J F M A M J J A S O N D Estimated Energy Recovery: 1680 MWh (~$84,000 or ~$12,000/yr) 0

21 Recommendations for Center St Worthington Turbine (112 kw) Generator Flow control is more beneficial than replacement of the existing turbine Modify existing D/S 14 BFV and integrate with SCADA for automatic remote modulation/throttling of flow 14 BFV

22 Turbine Evaluation Sensitivity 2007 Estimated Energy Recovery (MWh) Hourly Calculation Approach Average Flow and Pressure Approach 0 Existing 112 kw Turbine w/prv Cornell Turbine 6TR1 w/prv Cornell Turbine 6TR2 w/prv Cornell Turbine 5TR1A w/prv Cornell Turbine 10TR2 w/prv Considering diurnal and seasonal variabilities significantly impacts outcome of energy recovery estimates

23 Acknowledgments TVWD: Ryan Smith, Troy Van Roekel, Cheryl Welch, Mark Knudson Energy Trust of Oregon Contact Information: