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

LocationOracle, AZChesterfield, MOSagle, ID
Latitude32⁰34’47.38” N38⁰38’27.81” N48⁰13’49.38” N
Micro-inverter #2452 (flat panel)2369 (angled panel)2276 (flat panel)1951 (angled panel)6270 (flat panel)6277 (angled panel)
2015 May44.1 kWh44.1 kWh
2015 Jun41.2 kWh39.9 kWh
2015 Jul35.3 kWh34.4 kWh
2015 Aug36.6 kWh37.8 kWh
2015 Sep30.2 kWh34.3 kWh20.5 kWh26.0 kWh
2015 Oct27.1 kWh33.8 kWh13.4 kWh20.6 kWh
2015 Nov24.4 kWh35.5 kWhsnowsnow
2015 Dec19.7 kWh29.7 kWhsnowsnow
2016 Jan22.1 kWh32.3 kWhsnowsnow
2016 Feb28.7 kWh39.3 kWhsnowsnow
2016 Mar35.8 kWh43.8 kWh16.0 kWh17.8 kWh15.9 kWh18.8 kWh
2016 Apr40.0 kWh42.9 kWh28.4 kWh26.4 kWh26.8 kWh30.3 kWh
2016 May45.8 kWh47.1 kWh27.4 kWh17.9 kWh33.5 kWh30.7 kWh
2016 Jun39.6 kWh38.8 kWh25.0 kWh17.4 kWh36.1 kWh31.0 kWh
2016 Jul42.6 kWh41.6 kWh23.4 kWh16.6 kWh35.5 kWh32.7 kWh
2016 Aug37.5 kWh39.3 kWh17.4 kWh23.8 kWh
2016 Sep30.9 kWh34.6 kWh23.5 kWh21.0 kWh
2016 Oct30.9 kWh39.5 kWh23.1 kWh16.9 kWh
2016 Nov24.1 kWh34.4 kWh12.5 kWh21.0 kWh6.0910.4
2016 Dec15.0 kWh23.0 kWh8.9 kWh16.2 kWhsnowsnow
2017 Jan8.4 KWh12.5 kWhsnowsnow
2017 Feb15.3 kWh21.4 KWh15.3 KWh21.4 kWhsnowsnow
2017 Mar37.3 kWh44.2 KWh17.8 KWh22.4 kWhDamaged by snowNo longer in service
2017 Apr40.3 kWh43.7 KWh22.2 KWh21.8 kWh
2017 May45.2 kWh45.0 KWh24.7 KWh17.4 kWh
2017 Jun44.5 kWh43.2 KWh23.6 KWh16.3 kWh
2017 Jul37.4 kWh35.7 KWh25.7 KWh17.8 kWh
2017 Aug38.8 kWh40.3 KWh25.9 KWh18.6 kWh
2017 Sep35.2 kWh40.1 KWh23.8 KWh21.1 kWh
2017 Oct14.6 kWh18.4 KWh14.7 KWh19.4 kWh
2017 Nov21.8 kWh32.4 KWh12.0 KWh21.1 kWh