1. Economics of Solar PV By Dan Catlin Energy Consultant & Air Quality Specialist, Fort McDowell Yavapai Environmental Department For presentation at: National Tribal Forum on Air Quality May 1, 2013

2. Solar Photovoltaic systems where, why, how, and when? Yes…sun exposure is Important! Location, location, location. Environmental, economic, and policy. Good design is important. Competition helps keep cost down. Now vs. later and expected ROI.

3. New Energy Paradigm: Distributed Generation (DG) Economic Reasons…focus on Solar DG Environmental Reasons Security Reasons Political Reasons

4. Energy usage and cost history? Electric rate schedule(s)? Energy inflation? Capital cost? Interest rates? Utility incentives? Federal & State incentives? Purchase vs. Purchase Power Agreements (PPA) vs. leasing vs. do it yourself? Solar Economics & ?s to ask

5. Solar information websites http://rredc.nrel.gov/solar/calculators/PVW ATTS/version1/http://rredc.nrel.gov/solar/calculators/PVW ATTS/version1/ http://dsireusa.org/ http://www.arizonagoessolar.org/ http://maps.nrel.gov/imby https://sam.nrel.gov/ www.wholesalesolar.com www.pennysolar.com

6. Location considerations

8. Small office building PV Watts Near Phoenix, Arizona projected 12.1 kw system KWhr 18.4 0 tilt according array azimuth 180 0 to utility to EnlightenAC energy kwh AC/DC default Derate: 0.77 production AC/DC derate: 0.95 meter year 2011 January 1679 173014731190 February 1587 163016401327 March 2082 215020331646 April 2196 228023201883 May 2392 248024631998 June 2238 233022821850 July 2133 222022821849 August 2081 217022231802 September1903 198020331646 October 1849 191019361568 November 1455 1500 1535 1239 December 1335 137013961126 2011 totals 22,930 237502361619124 year 2012 January 1511 156014731190 February 1707 177016401327 March 2121 220020331646 April 2146 223023201883 May 2373 248024631998 June 2240 234022821850 July 1966 206022821849 August 1981 208022231802 September1827 192020331646 October 1922 201019361568 November 1591 1660 1535 1239 December 1407 147013961126 22,792 237802361619124

9. Why differences between projected and Actual Line loss between Enlighten system measurement & utility measurement. Possible different time of day measurements taken. Average cloud covering assumed by PVwatts & actual cloud covering. Overly conservative assumptions of PVwatts but still gave good ball park projections.

10. Energy cost savings @ 10 cents/kwh January 2011 $147.30 February 2011$164.00 March 2011$203.30 April 2011$232.00 May 2011$246.30 June 2011$228.20 July 2011$228.20 August 2011$222.30 September 2011$203.30 October 2011$196.60 November 2011$153.50 December 2011$139.60 2011 year total$2361.60

11. Return on Investment 54 PV modules Sharp 224 watt each 54 Enphase micro inverters Roof mounted March 2010 Installed cost of $52,644.60 $4.35/installed watt Using PVwatts & 10 cents/kwh –22.3 year payback or 4.5% ROI

12. Energy Cost Utility rate schedules Connection costs Demand charges Power factor charges Kilowatt-hour energy charges Time of Day & seasonal factors Future energy cost?? Energy storage and/or back-up power

13. Solar Advantage Covered Parking with PV LEED points Public Relations Easy-quick install with few approval issues Low maintenance needs Easy to monitor Proven technology

14. Urban Heat Island Problem Global Warming + City pavement = problem. Pavement absorbs solar energy & causes higher night time temperatures in cities. Shade is greatly appreciated in Central Arizona. Answer: more photovoltaic panels used shade pavement. Added benefit energy turned to electricity. Up to 20% of solar energy impacting commercially available solar modules converted to electricity rather than heat.

15. Apartment Complex-Mesa, AZ

17. ASU is setting example Covered parking with solar PV. Helps meet their sustainability goals. Possible lower cost electricity by use of PPAs (Purchase Power Agreements). Can charge more for the covered parking spaces.

22. Success Stories & Examples Competition is driving down the cost of installing Solar PV systems. Public support for renewable energy. Ramped up production. Employment.

23. Can start small

24. Works at Home also Tax credits Utility incentives Tax advantages (not taxed on what you save) May not impact property tax Increase value of home Great return on investment Inflation Hedge

27. Pole or roof mount or both

29. Title for next picture It’s not all about the environment If you build it they will come All work and no play makes for a dull existence Solar and water do mix Where would you like to be when it is 110 degrees outside? Lifestyle Decisions

31. Questions?? Dan Catlin Can be reached at 480-789-7166 Or 480-231-3703 dcatlin@ftmcdowell.org