NC AWWA-WEA Annual Conference November 12, 2013

1. It Pays to be Green: The State as a Funding Resource for WWTP Energy Efficiency and Green Projects NC Division of Water Infrastructure Francine Durso, PE NC AWWA-WEA Annual Conference November 12, 2013

2. Outline • CWSRF Loans for Green Projects • Wastewater Treatment Plant Energy Efficiency Projects • Overview of Program Changes in 2013 • 2013 Funding Levels

3. CWSRF Loans for Green Projects • Green Project Reserve within CWSRF • Since 2010, EPA requirement • Amount is 10% of annual Congressional funding • Green Project Types • Energy efficiency wastewater infrastructure • Reclaimed water systems • Stormwater BMPs • Stream/wetland/buffer restoration • 0% Interest Loans (not grants)

4. WWTP Energy Efficiency Projects • Primary purpose of project must be at least 20% energy reduction (or energy generation) • OWASA Mason Farm WWTP • Aeration System Replacement • Rocky Mount Tar River Regional WWTP • Oxygen Generator Replacement • Greenville Utilities Commission Tar River WWTP • UV Disinfection System Replacement

5. OWASA – 14.5 MGD Mason Farm WWTP

6. Aeration System Replacement • Project Driver – Aeration consumes nearly 53% of total plant energy usage • Project Goal • Reduce aeration system energy usage • Accomplished By: • Replacing jet aeration with fine bubble diffusers • Adding vertical mixers in aeration basins • Replacing old blowers with more efficient blowers • CWSRF Green Project loan at 0% for $6.56 million

7. Power Distribution of Major Components Reclaimed water pumped to UNC Peak Month > 1.4 MGD Aeration consumes nearly 53% of total plant energy usage

8. Aeration System Replacements • New fine bubble diffused aeration system • Vertical hyperboloid mixers • New air header 4 new blowers and controls

9. Old Aeration Equipment

10. Old Blowers

11. Aeration System Replacements Air supply pipe Blowers Mixers Fine Bubble Diffusers

12. Hyperboloid Mixers and Diffusers Mixing Pattern

13. Project Benefits • Reduces aeration and mixing energy use by more than 60% compared to existing equipment • Reduces total plant electrical use by more than 30% • Peak hour electrical demands expected to be reduced by similar percentages

14. Rocky Mount – 21 MGD Tar River Regional WWTP Pure oxygen plant needed to treat high strength industrial wastes

15. Oxygen Generator Replacement • Project Driver • Pure oxygen from cryogenic system • Plant flows decreasing; wasting most of O2 produced • Energy costs increasing • Project Goal • Reduce oxygen generation system energy usage • Accomplished By: • Replacing cryo plant with vacuum pressure swing adsorption (VPSA) system • CWSRF Green Project loan at 0% for $2.34 million • Payments = $117,000/year

16. Cryo Plant Issues • Designed for 21 MGD • Operated either “on” or “off” • No turndown/idle • Discharged 1/2 to 2/3 of oxygen generated to atmosphere • Energy costs increasing

17. Alternative Needed • With closing of most textile plants, plant flows average 9 MGD • To reduce energy costs, needed to match oxygen generation to plant flows • VPSA provides: • Unit customized to tonnage needed • Turndown/idle time control from 100% to 0% • “Shoe box-size” PLC instead of 20-ft long control panels, hundreds of wires, multiple control stations

18. Rocky Mount – 21 MGD Tar River Regional WWTP Old Cryo Plant New VPSA System in Building

19. One 700 HP motor drives 2 blowers: one vacuum and one pressure VPSA System Vacuum/pressure vessels and storage

20. Project Benefits • Reduces energy used for oxygen generation by 72% compared to existing equipment • Reduces O&M cost of: • “Defrost” ($15K/yr) • Rebuild of two 1,000 HP compressors and turbines ($125K every 4 years) • Significantly reduces noise complaints by neighbors Download data to flash drive

21. GUC – 17.5 MGD Tar River WWTP

22. Existing UV System • Medium pressure, high intensity • Advantages – reduced footprint and number of lamps • Disadvantages – higher power cost and shorter lamp life • Installed in 1994 and 1996

23. UV System Replacement • Project Driver • Approaching useful life of system • Project Goal • Replace aging and inefficient equipment • Reduce UV system energy usage • Accomplished By: • Replacing existing UV with new low pressure, high intensity system

24. UV System Replacement • CWSRF Green Project loan at 0% for $3.36 million • Payments = $168,000/year • Savings = $50,000/year • New UV System • Low pressure, high intensity system • Reduced energy requirements • Longer lamp life

25. Project Benefits at 11 MGD Annual Average Flow 80% reduction

26. Overview of Program Changes in 2013

27. Overview of Program Changes in 2013 • New Division of Water Infrastructure created • Former Infrastructure Finance Section (DWQ) • Former Public Water Supply Section Loans & Grants (DWR) • New State Water Infrastructure Authority created • 9 member authority • 2-year appointments

28. State Water Infrastructure Authority Member Designations

29. 2013 CWSRF Funding Levels

30. 2013 CWSRF Funding Levels • Federal Appropriations (Congress) • Nationally = +/- $1.4 Billion • North Carolina = $24 Million (1.8% of national since 1987) • State Match = $4.8 Million (20%) • Green Project Reserve • $2.4 Million (10%)

31. Historic Federal Appropriations for NC • Amounts include State Match (20%) ARRA Years

32. Federal Appropriations and State Match • Since 1987, $123 Million in state match resulted in $1.5 Billion in commitments • Due to revolving nature of the loan program Commitments Commitments Federal Share State Match

33. Wrap Up and Questions

34. CWSRF Application Deadlines: March 1 and September 1 Website: http://portal.ncdenr.org/web/wi/

35. Wrap Up and Questions

36. OWASA Average Energy Use Breakdown