Mitigation
Cleaning schedule optimization
- ID
mit:cleaning-schedule-optimization- IRI
https://solarlattice.org/kb/mit/cleaning-schedule-optimization- Status
- active
- Also known as
- Best-Time-to-Clean models, optimal cleaning schedule, cleaning frequency optimization, optimal cleaning interval, Triggered Cleaning
Cleaning schedule optimization means picking when and how often to clean modules so the value of energy recovered outweighs the cost of cleaning. It addresses soiling losses, including granular dust soiling and fungal bio-soiling, where cleaning triggers should be set by the value of the lost energy. The simplest rule is to clean once the revenue lost to soiling exceeds the cost of a cleaning, but more detailed models also account for free cleaning by rain, wind or dew. Key inputs are cleaning cost, soiling accumulation rate, capacity factor, electricity price and module efficiency, so the schedule must be set per site and may vary by season or by area within a site. Soiling sensors or real-time soiling data, together with a soiling model calibrated against operational data, help decide the most profitable time to clean. In one Abu Dhabi plant comparison, triggered cleaning gave the lowest total cost, below both periodic cleaning and relying on natural cleaning. Limits: rain right after a triggered cleaning can make the benefit hard to judge, and advanced models are harder to apply because soiling and rainfall vary from year to year. Where persistent fungal deposits are present, treat cleaning as required maintenance and do not assume rain will restore output.
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- sentence 5: support check: partial - Real-time soiling data/sensors and soiling models are supported for deciding best time to clean, but calibration against operational data is only in the diagnostic workflow (updating model if mismatched), loosely stated.
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Claims
typical_power_loss
c1 verified · fact
nominal 1.91 PERCENT
Conditions: Annual soiling loss with no cleaning, simulated for a system in Mesa, Arizona (Naeem 2014)
verified by: joshuahamsaverified on: 2026-10-20review note: possible conflict with c2 (same source; check the conditions); possible conflict with c3 (same source; check the conditions); possible conflict with c4 (same source; check the conditions); possible conflict with c5 (same source; check the conditions); reviewer: the compiler-flagged conflict is a different scenario or technology, not disagreement
c2 verified · fact
nominal 1.52 PERCENT
Conditions: Annual soiling loss with one cleaning per year, same Mesa, Arizona simulation
verified by: joshuahamsaverified on: 2026-10-20review note: possible conflict with c1 (same source; check the conditions); possible conflict with c3 (same source; check the conditions); possible conflict with c4 (same source; check the conditions); possible conflict with c5 (same source; check the conditions); reviewer: the compiler-flagged conflict is a different scenario or technology, not disagreement
c3 verified · fact
nominal 1.32 PERCENT
Conditions: Annual soiling loss with two cleanings per year, same Mesa, Arizona simulation
verified by: joshuahamsaverified on: 2026-10-20review note: possible conflict with c1 (same source; check the conditions); possible conflict with c2 (same source; check the conditions); possible conflict with c4 (same source; check the conditions); possible conflict with c5 (same source; check the conditions); reviewer: the compiler-flagged conflict is a different scenario or technology, not disagreement
c4 verified · fact
nominal 1.2 PERCENT
Conditions: Annual soiling loss with three cleanings per year, same Mesa, Arizona simulation
verified by: joshuahamsaverified on: 2026-10-20review note: possible conflict with c1 (same source; check the conditions); possible conflict with c2 (same source; check the conditions); possible conflict with c3 (same source; check the conditions); possible conflict with c5 (same source; check the conditions); reviewer: the compiler-flagged conflict is a different scenario or technology, not disagreement
c5 verified · fact
4.3–7.5 PERCENT
Conditions: Reported annual soiling losses across studies, where special soiling conditions require scheduled cleaning
verified by: joshuahamsaverified on: 2026-10-20review note: possible conflict with c1 (same source; check the conditions); possible conflict with c2 (same source; check the conditions); possible conflict with c3 (same source; check the conditions); possible conflict with c4 (same source; check the conditions)
c6 verified · fact
5–11 PERCENT
Conditions: Persistent production loss from fungal bio-soiling in humid subtropical regions, which should be included in cleaning schedules
verified by: joshuahamsaverified on: 2026-10-20review note: reviewer: the compiler-flagged conflict is a different scenario or technology, not disagreement
Referenced by
Data