We have compiled the module cleaning guidelines from the Warranty and Installation Documents of different PV modules about Soiling & Cleaning which are as follows:

1. JINKO Solar

• Warranty Document:

Exclusions: subject to direct contact with corrosive agents or salt water; pest damage; or malfunctioning PV system components;

• Installation Manual:

Site selection: Do not install the PV module in a location where it would be immersed in water or continually exposed to water from a sprinkler or fountain etc.

A buildup of dust or dirt on the module(s) front face will result in a decreased energy output. Clean the panel(s) preferably once per annum if possible (depend on site conditions) using a soft cloth dry or damp, as necessary. Water with high mineral content may leave deposits on the glass surface and is not recommended.

Never use chemicals when cleaning modules as this may affect the module warranty and energy output.

2 TRINA Solar

• Warranty Document:

Exclusions and Limitations: exposure to any of the following: extreme thermal or environmental conditions or rapid changes in such conditions, corrosion, oxidation, unauthorized modifications or connections, unauthorized opening, servicing by use of unauthorized spare parts, accident, force of nature (such as lightning strike, earthquake), influence from chemical products or other acts beyond Trina Solar’s reasonable control (including damage by fire, flood, etc.);

• Installation Manual:

Site Selection: According to Intertek-conducted IEC 61701, salt mist corrosion testing of Photovoltaic (PV), Trina Solar modules can be installed in corrosive salt areas within proximity of the ocean or sulfurous areas. The module must not be soaked in the water or in the environment (i.e., fountain, spindrift, etc.) where the module would touch water (pure water or brine) for a long term. If the modules are placed in an environment of salt fog (i.e., marine environment) or sulfur (i.e., sulfur sources, volcanoes, etc.), there is a risk of corrosion.

Cleaning: If there are greasy dirt and other substances on the surface of the PV module which are difficult to clean, conventional household glass cleaning agents can be used; Do NOT use the alkaline and strong acid solvents.

Water Requirements: REQUIREMENTS FOR WATER QUALITY

PH: 5 ~7;

Chloride and Salinity ： 0 – 3,000 mg/L

Turbidity ： 0-30 NTU

Conductivity ： 1500~3000 μs/cm

Total dissolved solids (TDS)： ≤1000 mg/L

Water Hardness—calcium and magnesium ions ： 0-40 mg/L

Non-alkaline water must be used; demineralized water shall be used if the condition permits.

3 Canadian Solar:

• Warranty Document:

Exception: which has been subjected to extraordinary salt or chemical exposure;

• Installation Manual:

Environmental Conditions:

Do not immerse modules in water or constantly expose modules to water (either fresh or salt) (i.e. from fountains, sea spray).

Exposing modules to salt (i.e. marine environments) or sulfur (i.e. sulfur sources, volcanoes) incurs the risk of module corrosion.

Failure to comply with these instructions will void Canadian Solar Inc. warranty.

Module Cleaning Guideline:

Do not use cleaning corrosive solutions containing acid, alkali, acetone, or industrial alcohol.

Canadian Solar Inc. recommends to avoid rotating brush cleaning methods, as they could create micro-cracks in the PV modules.

Dirt must never be scraped or rubbed away when dry, as this will cause micro- scratches on the glass surface.

We recommend the following to be used:

Water with low mineral content

Near neutral pH water

The maximum water pressure recommended is 4 MPa (40 bar)

Wet Cleaning:

If excessive soiling is present on the module surface, a non-conductive brush, sponge, or other mild agitating method may be used with caution.

Ensure that any brushes or agitating tools are constructed with non-conductive materials to minimize risk of electric shock and that they are not abrasive to the glass or the aluminum frame.

If grease is present, an environmentally friendly cleaning agent may be used with caution.

4 JA Solar:

• Warranty Document:

Exception:  No Major Mention Out Clearly. All general Terms.

• Installation Manual:

Installation Condition: Installation position and working environment:

Modules must not be installed or operated in areas where, salt, hail, snow, sand, dust, air pollution, chemically active vapors, acid rain, soot, etc., are excessive. Modules must not be sited in locations where aggressive substances such as salt or salt-water, or any other type  of corrosive agent, could affect the safety and/or performance of the Modules.

Please adopt appropriate measures to ensure the performance and safety of the Modules when they are installed or operated in the areas where produces heavy snow, extremely cold, strong wind, or near the island or desert where is prone to produce salt fog, or near water.

Operation and Maintenance:

In many instances the front subs substrate goes cleaned with the rain, and we can decrease the cleaning frequency. It is recommended to wipe the glass surface with wet sponge or soft cloth. Please do not clean the glass with cleaning agent which contains acid or alkali.

5 HANWHA Solar

• Warranty Document:

Exclusions: Damage caused by extreme environmental sources of impact, including, but not limited to (i) acid rain or snow, (ii) blowing sand, (iii) saline air, (iv) pollution of  any kind in the air, soil or groundwater, (v) unusual oxidation levels, (vi) mold, or (vii) any nearby fire, explosion, smoke or charring;

• Installation Manual: Does not have clear Instructions or Note for cleaning.