1. Mapping Rooftop Solar Power Potential in Greater Cincinnati Brandon Flessner GIS Analyst OKI Regional Council of Governments 2015 Ohio GIS Conference September 21 - 23, 2015 | Hyatt Regency Columbus| Columbus, Ohio

2. Solar Ready Grant

3. Map Demo

4. Data Building Footprints Provided by counties, Open Street Map ~700k polygons LiDAR Provided by OSIP, KYFromAbove, IndianaMap ~9.8 billion points

5. Digital Surface Model (DSM)

6. Area Solar Radiation

7. Demo Analysis

8. Identify Roof Planes

9. Overlay Usable Areas “Usable” Roof Aspects “Usable” Solar Radiation “Usable” Roof Area

10. System Size Left Building Example: 92 cells (6.25 ft 2 / cell) = 575 ft 2 of usable roof area Residential solar panel 40” X 66” or 18.3 ft 2 (0.25 kW) About 31.4 panels would fit in usable area System Size = 7.86 kW

11. Adjustment by roof type Flat roofs: Slope less than 22 degrees Usable area = usable solar radiation System size down rated for OSHA requirements, extra mounting hardware, spacing Aspect and slope are constants (180, 10) Simple roofs Less than 6 roof planes Usable area = overlay of usable solar radiation and usable roof planes Aspect and Slope = average value of largest roof plane Complex roofs 6 or more roof planes Usable area = overlay of usable solar radiation and single largest roof plane Aspect and Slope = average value of largest roof plane

12. Annual Power Generation Incorporate Typical Meteorological Year data for Lunken Airport, Cincinnati, via PVWatts Build dataset of typical values for system size, aspect, slope and annual output. Calculate equation via multiple linear regression Apply equation Annual output (kWh) = -544.27+1148.0277 * System Size - 0.1515 * Aspect + 15.2126 * Slope

13. Economics Annual Savings Annual output (kWh) * retail price of electricity ($/kWh) Ohio = 9.16 cents / kWh Installation costs $3.30 per installed watt 4 kW system would cost about $13,200

14. Other Considerations Python Accuracy Time Website

15. solar.oki.org/map Questions?? Contact Info: Brandon Flessner bflessner@oki.org 513-629-7700