{"schemaVersion":1,"releaseVersion":"pv-cleaning-cost-reference-2026-07-v1","methodVersion":"pv-cleaning-cost-reference-v1","publishedAt":"2026-07-28T00:00:00+08:00","scope":"Segment-specific cleaning cost references in original source currencies and cost bases.","interpretation":"Reference-only evidence. Rows are not current local market quotes, and event costs are not annualised without a documented frequency.","rowCount":7,"rows":[{"reference_key":"almeria-rooftop-ciesol-2020","evidence_source_key":"ciesol-almeria-cleaning-2020","source_location":"Almeria, Spain","country_code":"ES","geographic_scope":"site","geographic_basis":"direct_observation","applicability":"reference_only","segment":"commercial_rooftop","system_size_kwp":9,"mounting_access":"Low-rise university research facility roof","cleaning_method":"Manual cleaning intervention","currency":"EUR","price_year":2020,"cost_per_kw_event":3.4656,"documented_cleanings_per_year":null,"frequency_basis":null,"documented_annual_cost_per_kw_year":null,"scenario_basis":"event_cost_only","includes_non_cleaning_costs":false,"source_title":"Analysis of the Soiling Effect on the Performance of Photovoltaic Systems on the Almeria University Campus","source_publisher":"Energies","source_url":"https://www.mdpi.com/1996-1073/13/23/6376","doi":"10.3390/en13236376","publication_year":2020,"data_confidence":"Medium","limitations":"Single research system and historical local labour basis. The intervention does not establish an annual cleaning frequency.","notes":"EUR 31.19 per intervention divided by 9 kWp equals EUR 3.4656/kW-event. Maintenance cost exceeded the avoided soiling loss in the study period.","retrieved_at":"2026-07-28T00:00:00+00:00"},{"reference_key":"morocco-mining-utility-ghennioui-2026","evidence_source_key":"ghennioui-morocco-cleaning-2026","source_location":"Moroccan mining site","country_code":"MA","geographic_scope":"site","geographic_basis":"direct_observation","applicability":"reference_only","segment":"utility_ground_mounted","system_size_kwp":44000,"mounting_access":"Ground-mounted utility plant in a dusty mining environment","cleaning_method":"Manual night cleaning","currency":"USD","price_year":2026,"cost_per_kw_event":0.215,"documented_cleanings_per_year":14,"frequency_basis":"observed_program","documented_annual_cost_per_kw_year":3.01,"scenario_basis":"event_cost_times_documented_frequency","includes_non_cleaning_costs":false,"source_title":"Optimizing photovoltaic cleaning in dusty mining environments: Energy and economic gains from dynamic scheduling","source_publisher":"Results in Engineering","source_url":"https://doi.org/10.1016/j.rineng.2026.110081","doi":"10.1016/j.rineng.2026.110081","publication_year":2026,"data_confidence":"High","limitations":"Industrial mining conditions, manual night work and utility scale. It is not a Casablanca residential proxy.","notes":"USD 9,460/event divided by 44,000 kWp equals USD 0.215/kW-event. Fourteen events annualise to USD 3.01/kW-year. The reported USD 5.23/kW-year is net economic gain after cleaning, not cleaning cost.","retrieved_at":"2026-07-28T00:00:00+00:00"},{"reference_key":"perth-residential-tanesab-2016","evidence_source_key":"tanesab-perth-cleaning-2016","source_location":"Perth, Western Australia","country_code":"AU","geographic_scope":"site","geographic_basis":"direct_observation","applicability":"reference_only","segment":"residential_rooftop","system_size_kwp":1.5,"mounting_access":"Small residential rooftop field system","cleaning_method":"Manual cleaning intervention","currency":"AUD","price_year":2016,"cost_per_kw_event":52,"documented_cleanings_per_year":null,"frequency_basis":null,"documented_annual_cost_per_kw_year":null,"scenario_basis":"event_cost_only","includes_non_cleaning_costs":false,"source_title":"Dust Effect and its economic analysis on PV modules deployed in a temperate climate zone","source_publisher":"Murdoch University","source_url":"https://researchportal.murdoch.edu.au/esploro/outputs/journalArticle/Dust-Effect-and-its-economic-analysis/991005545031207891","doi":null,"publication_year":2016,"data_confidence":"Medium","limitations":"One historical small-system study. It is not a current Perth service quote and does not establish an annual cleaning frequency.","notes":"AUD 78 per intervention divided by the companion study system size of 1.5 kWp equals AUD 52/kW-event. The reported avoided production loss was AUD 5.47.","retrieved_at":"2026-07-28T00:00:00+00:00"},{"reference_key":"southern-spain-utility-high-cost-2025","evidence_source_key":"iea-pvps-southern-spain-2025","source_location":"Southern Spain","country_code":"ES","geographic_scope":"regional","geographic_basis":"modelled_scenario","applicability":"reference_only","segment":"utility_ground_mounted","system_size_kwp":30000,"mounting_access":"Ground-mounted utility plant","cleaning_method":"Wet tractor cleaning by an external service provider","currency":"EUR","price_year":null,"cost_per_kw_event":0.75,"documented_cleanings_per_year":0.2,"frequency_basis":"modelled_optimum","documented_annual_cost_per_kw_year":0.15,"scenario_basis":"event_cost_times_documented_frequency","includes_non_cleaning_costs":false,"source_title":"Climate-Specific Performance and Energy Rating of PV Modules and Systems","source_publisher":"IEA PVPS Task 13","source_url":"https://www.csp.fraunhofer.de/content/dam/imws/csp/de/documents/task-13-reports/systeme/IEA-PVPS-T13-32-2025-REPORT-Climate-Optimisation-2025.pdf","doi":null,"publication_year":2025,"data_confidence":"Medium","limitations":"Utility-scale optimisation scenario, not an observed residential price or a current market quote.","notes":"EUR 750/MWp-event equals EUR 0.75/kW-event. At the modelled optimum of 0.2 cleanings/year, the scenario annualises to EUR 0.15/kW-year.","retrieved_at":"2026-07-28T00:00:00+00:00"},{"reference_key":"southern-spain-utility-low-cost-2025","evidence_source_key":"iea-pvps-southern-spain-2025","source_location":"Southern Spain","country_code":"ES","geographic_scope":"regional","geographic_basis":"modelled_scenario","applicability":"reference_only","segment":"utility_ground_mounted","system_size_kwp":30000,"mounting_access":"Ground-mounted utility plant","cleaning_method":"Wet tractor cleaning by an external service provider","currency":"EUR","price_year":null,"cost_per_kw_event":0.25,"documented_cleanings_per_year":1.3,"frequency_basis":"modelled_optimum","documented_annual_cost_per_kw_year":0.325,"scenario_basis":"event_cost_times_documented_frequency","includes_non_cleaning_costs":false,"source_title":"Climate-Specific Performance and Energy Rating of PV Modules and Systems","source_publisher":"IEA PVPS Task 13","source_url":"https://www.csp.fraunhofer.de/content/dam/imws/csp/de/documents/task-13-reports/systeme/IEA-PVPS-T13-32-2025-REPORT-Climate-Optimisation-2025.pdf","doi":null,"publication_year":2025,"data_confidence":"Medium","limitations":"Utility-scale optimisation scenario, not an observed residential price or a current market quote.","notes":"EUR 250/MWp-event equals EUR 0.25/kW-event. At the modelled optimum of 1.3 cleanings/year, the scenario annualises to EUR 0.325/kW-year.","retrieved_at":"2026-07-28T00:00:00+00:00"},{"reference_key":"southern-spain-utility-mid-cost-2025","evidence_source_key":"iea-pvps-southern-spain-2025","source_location":"Southern Spain","country_code":"ES","geographic_scope":"regional","geographic_basis":"modelled_scenario","applicability":"reference_only","segment":"utility_ground_mounted","system_size_kwp":30000,"mounting_access":"Ground-mounted utility plant","cleaning_method":"Wet tractor cleaning by an external service provider","currency":"EUR","price_year":null,"cost_per_kw_event":0.5,"documented_cleanings_per_year":0.5,"frequency_basis":"modelled_optimum","documented_annual_cost_per_kw_year":0.25,"scenario_basis":"event_cost_times_documented_frequency","includes_non_cleaning_costs":false,"source_title":"Climate-Specific Performance and Energy Rating of PV Modules and Systems","source_publisher":"IEA PVPS Task 13","source_url":"https://www.csp.fraunhofer.de/content/dam/imws/csp/de/documents/task-13-reports/systeme/IEA-PVPS-T13-32-2025-REPORT-Climate-Optimisation-2025.pdf","doi":null,"publication_year":2025,"data_confidence":"Medium","limitations":"Utility-scale optimisation scenario, not an observed residential price or a current market quote.","notes":"EUR 500/MWp-event equals EUR 0.50/kW-event. At the modelled optimum of 0.5 cleanings/year, the scenario annualises to EUR 0.25/kW-year.","retrieved_at":"2026-07-28T00:00:00+00:00"},{"reference_key":"us-residential-pvscm-2024q1","evidence_source_key":"nrel-pvscm-2024q1","source_location":"United States national residential reference","country_code":"US","geographic_scope":"national","geographic_basis":"national_model","applicability":"reference_only","segment":"residential_rooftop","system_size_kwp":8,"mounting_access":"Residential roof; homeowner time represented at equivalent commercial service cost","cleaning_method":"One annual module cleaning and inspection allowance","currency":"USD","price_year":2023,"cost_per_kw_event":null,"documented_cleanings_per_year":1,"frequency_basis":"reference_assumption","documented_annual_cost_per_kw_year":1.6588,"scenario_basis":"area_cost_divided_by_efficiency","includes_non_cleaning_costs":true,"source_title":"U.S. Solar Photovoltaic System and Energy Storage Cost Benchmarks, With Minimum Sustainable Price Analysis: Q1 2024","source_publisher":"U.S. Department of Energy and National Renewable Energy Laboratory","source_url":"https://data.nlr.gov/submissions/307","doi":"10.7799/3007269","publication_year":2024,"data_confidence":"High","limitations":"National US model, not a city quote. The input bundles module cleaning with vegetation and pest control.","notes":"USD 0.35/m2-year divided by 0.211 kW/m2 equals USD 1.6588/kW-year. Benchmark costs are reported in 2023 USD.","retrieved_at":"2026-07-28T00:00:00+00:00"}]}