Not much. Even in the relatively high-labor-cost United States, only 12% of utility scale solar project costs are attributable to installation labor. See table

Not much. Even in the relatively high-labor-cost United States, only 12% of utility scale solar project costs are attributable to installation labor. See table 14 on page 56 of this report: https://www.nrel.gov/docs/fy17osti/68925.pdf https://www.nrel.gov/docs/fy17osti/68925.pdf