|1,921,582||hectares of parking, USA [reference]|
|259||hectares/ sq mi|
|7,419||sq mi of parking in the USA|
|27,878,400||sq ft/sq mi|
|206,836,415,555||sq ft of parking in the USA|
|1,394||electricity, watts/capita (continuous) [reference]|
|0.19||capacity factor, solar|
|734||sf required per capita|
|281,914,770||population that could be served by solar panels over parking in the USA|
|276,000,000||population of the USA|
|102%||percentage that could be served by solar panels over parking in the USA|
Following this logic, with 13,998,033 hectares in the USA devoted to roadways, 744% of the population could be served by solar panels over all roadways in the USA. [reference]
And in like fashion, the roofs on residences alone could handle 50% of all electrical demand in the USA. [reference] On average, there is more than enough sunlight landing on the roof of a home to meet its own power requirements.
For detailed calculations, see spreadsheet.