Data Collection Test Site Results

Since Solar Road Panels must be laid flat, unlike rooftop solar, we are collecting data at different latitudes to compare the difference in energy harvesting. We take regular store-bought solar panels and angle one to the south at the optimal angle for that latitude and place the other flat.

In April of 2015, a collection site was installed in southern Arizona at the Biosphere 2 in Oracle, Arizona. A second site was set up at Solar Roadways in Sagle, Idaho in August 2015. A third site was set up at the Missouri DOT Transportation Research Center in Chesterfield, Missouri in March 2016.

The Sagle, ID site uses 220W solar panels and the Oracle, AZ and Chesterfield, MO sites use 250W solar panels.

As can be seen from the data collected so far, the flat panels generate more energy than the tilted panels during overcast days. We believe this is because the photons are scattered on overcast days, and during such times, it is easier for them to land on a flat surface than one which is angled.

"Snow" indicates months where no data was collected because the panels were covered in snow and collected zero solar energy. Keep in mind that Solar Roadways will collect solar energy in every kind of weather as the panels will never be covered in snow thanks to our heating elements.

We are comparing the energy generated from solar panels laid flat (as they will be for Solar Roadways installations) vs energy generated from panels angled for each given latitude the way it's done for solar farms or rooftop panels. The data thus far is surpassing our expectations.

Each of these Data Collection Sites will soon receive a complimentary SR3 panel to diplay to thank them for their participation in this program. We are currently considering two more data collection sites: one below the 32 degrees N latitude and the other above the 49 degrees N latitude. They should be high visibility areas with an open southern exposure.

Test site at MoDOT

Location Oracle, AZ Chesterfield, MO Sagle, ID
Latitude 32⁰34’47.38” N 38⁰38’27.81” N 48⁰13’49.38” N
Micro-inverter # 2452 (flat panel) 2369 (angled panel) 2276 (flat panel) 1951 (angled panel) 6270 (flat panel) 6277 (angled panel)
2015 May 44.1 kWh 44.1 kWh - - - -
2015 Jun 41.2 kWh 39.9 kWh - - - -
2015 Jul 35.3 kWh 34.4 kWh - - - -
2015 Aug 36.6 kWh 37.8 kWh - - - -
2015 Sep 30.2 kWh 34.3 kWh - - 20.5 kWh 26.0 kWh
2015 Oct 27.1 kWh 33.8 kWh - - 13.4 kWh 20.6 kWh
2015 Nov 24.4 kWh 35.5 kWh - - snow snow
2015 Dec 19.7 kWh 29.7 kWh - - snow snow
2016 Jan 22.1 kWh 32.3 kWh - - snow snow
2016 Feb 28.7 kWh 39.3 kWh - - snow snow
2016 Mar 35.8 kWh 43.8 kWh 16.0 kWh 17.8 kWh 15.9 kWh 18.8 kWh
2016 Apr 40.0 kWh 42.9 kWh 28.4 kWh 26.4 kWh 26.8 kWh 30.3 kWh
2016 May 45.8 kWh 47.1 kWh 27.4 kWh 17.9 kWh 33.5 kWh 30.7 kWh
2016 Jun 39.6 kWh 38.8 kWh 25.0 kWh 17.4 kWh 36.1 kWh 31.0 kWh
2016 Jul 42.6 kWh 41.6 kWh 23.4 kWh 16.6 kWh 35.5 kWh 32.7 kWh
2016 Aug 37.5 kWh 39.3 kWh 17.4 kWh 23.8 kWh - -
2016 Sep 30.9 kWh 34.6 kWh 23.5 kWh 21.0 kWh - -
2016 Oct 30.9 kWh 39.5 kWh 23.1 kWh 16.9 kWh - -
2016 Nov 24.1 kWh 34.4 kWh 12.5 kWh 21.0 kWh 6.09 10.4
2016 Dec 30.9 kWh 34.6 kWh 23.5 kWh 21.0 kWh snow snow