For a large 1000 MW solar plant, manual cleaning is highly labor-intensive and inefficient for the entire array size, but specific equipment designs have been developed to make labor-assisted cleaning more feasible and effective

 For a large 1000 MW solar plant, manual cleaning is highly labor-intensive and inefficient for the entire array size, but specific equipment designs have been developed to make labor-assisted cleaning more feasible and effective. These designs often involve using specialized tools with long reach and integrated water systems to improve efficiency and safety. 

The primary manual and labor-assisted module cleaning equipment designs used in large-scale solar plants are:

Telescopic Water-Fed Poles with Soft Brushes: This is one of the most common methods.

Design: These systems use lightweight, extendable poles (made of fiberglass or carbon composite, up to 14 meters long) with soft nylon or microfiber brushes at the end. A hose runs inside or alongside the pole, delivering purified water directly to the brush head.

Operation: Laborers can often clean panels from the ground or safe access points, reducing the safety risks associated with working at height. The water flow helps to lift the dirt, while the soft brush gently scrubs the surface.

Effectiveness: Effective for removing light to moderate dust and grime, and the use of deionized or purified water helps prevent mineral deposits/streaks.

Motorized Rotating Brush Systems (Manual/Semi-Automatic): This design incorporates a mechanical aid to boost labor efficiency.

Design: A brush head (often dual, counter-rotating discs to balance forces) is powered by a small electric motor or the water pressure itself. This assembly is attached to an extendable pole.

Operation: A laborer guides the motorized brush across the panels, while the motor provides the scrubbing action, reducing physical effort. These systems are often used with a water supply via a high-pressure cleaner or a portable water unit.

Effectiveness: Highly efficient for removing stubborn dirt, bird droppings, and industrial pollutants, achieving a high level of cleanliness with less manual exertion compared to simple static brushes.

Portable Water Sprayer Systems / Pipe and Nozzle Systems: This method relies more on water infrastructure than elaborate tools.

Design: Includes a network of pipes with tap assemblies and nozzles laid out across the solar farm, connected to a water source and booster pumps.

Operation: Laborers manually operate valves to spray water onto the panels. This is a basic form of manual cleaning that requires significant water volume and manual oversight to ensure even coverage and avoid water spots (requiring deionized water).

Effectiveness: Best for light dust in areas where water is readily available and not restricted. It is generally a less efficient method for heavy grime compared to brush-based systems.

Basic Manual Tools: For spot cleaning or very small-scale work within the large plant.

Design: Microfiber cloths, soft sponges, and plastic squeegees.

Operation: Requires direct human contact with the panel surface, which is labor-intensive and poses a safety risk on large, elevated arrays.

Effectiveness: Suitable for minor touch-ups, but not practical for the systematic cleaning of a 1000 MW plant. 

For a massive 1000 MW solar plant, efficiency dictates the use of more automated or semi-automated systems; however, for tasks specifically assigned to labor, motorized rotating brushes with water-fed, extendable poles offer the best balance of manual control, cleaning effectiveness, and efficiency.