Clean solar panels ensure higher output and efficient energy conversion. Energy output from solar panels is determined by factors such as the installation, amount of sun, direction, tilt and the cleanliness of the surface.
Most of the solar panels are self cleaning if the tilt angle allows, however, this does not happen when the tilt is small and the panel is almost horizontal. The horizontally installed solar panel will have dirt settling and building up on the surfaces and drastically reducing its efficiency.
It is important to regularly clean the solar panels in order to get the maximum benefits from the installation. The frequency of cleaning depends on the environment and amount of dirt.
When dirt settles on the surfaces, it reduces the amount and intensity of the sun that reaches the solar cells, hence reducing the power output and efficiency. Losses of up to 25 % or more may be experienced with dirty solar panels.
The most common sources of dirt are
• Bird droppings
• Dust from the atmosphere, wind, construction sites and traffic
• Dead insects
• Oily stains may occur if near an airport or if installation is under a flight path, near a major road frequented by trucks.
Physical inspection and removal of debris and dust and any other dirt should be done regularly based on the manufacturer’s specifications and the environment.
Another way of knowing when to clean is by use of monitoring systems. This will confirm if the system gives its expected output, in some configurations, alerts or system information can be accessed online using a tablet, a Smartphone or a wall mounted device.
Solar panel glass cleaning
Method used for cleaning solar panel surfaces depends on type of dirt, height of the panels, tilt, structure on which they are installed on, budget and much more. In general, warm water and soap are used to clean normal dirt, and isopropyl alcohol for oily stains. An appropriate tool such as a soft brush, plastic blade and cloth covered sponge are then used to clean and squeeze out the water. In other situations, a water hose equipped with a suitable nozzle can also be used.
Solar panel cleaning methods
- Simple cleaning with warm water and soap, this can be performed by the owner if they are within reach and accessible with ease. The other option is to use a cleaning service company and especially if they are roof mounted and risky to reach.
- Using Nano-Cleaning products on the solar panels makes them easy to clean and effective in areas where it rains often. The rain washes down the entire dirt and leaves them clean as new without having to scrub the surfaces. If the area is dry, a garden or air horse is used.
- There are several solar panel glass cleaning robots and these may differ in size, operations, cost, and other features depending on the manufacturer. Some of the leading brands of solar cleaning robots are Kyocera, Sharp, Suntech, Mitsubishi, Serbot, Gekko, Sanyo, Scrobby, Ecoppia, and others.
- Use of automatic systems such as the Heliotex Solar Cleaning Systems. This uses a system with pipes along the panels and soap container and controllers. The automated system can be programmed to do the cleaning at the desired frequency using Smartphone apps or web based applications.
Despite the fact that there are other factors that determine the amount of electricity a solar panel produces, dirt is one of the biggest and probably the easiest to rectify.