To put some numbers on it, at the end of 2016, average US utility-scale PV O&M costs were $18,000 per megawatt-AC per year (and still falling rapidly): https:/

To put some numbers on it, at the end of 2016, average US utility-scale PV O&M costs were $18,000 per megawatt-AC per year (and still falling rapidly): https://www.solarpowerworldonline.com/2017/09/berkeley-labs-2016-utility-scale-solar-report-finds-solar-pv-increasingly-competitive/ https://www.solarpowerworldonline.com/2017/09/berkeley-labs-... Average capacity factor for utility scale solar PV is 27% in the US: https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_6_07_b https://www.eia.gov/electricity/monthly/epm_table_grapher.ph... That would put O&M costs at 18000 / (24 * 365 * 0.27) = $7.60 per megawatt hour, out of a total price quoted by epistasis of $30-$32 per megawatt hour. O&M could be up to 25% of total costs. It is indeed, a significant part of total costs. It is also a smaller fraction of total costs dedicated to O&M than wind or fossil power (including fuel in O&M).