From EGP Innovation: The Robot that “Cleans” the Sun
Imagine having to remove dirt from a surface that spreads out for several square kilometres. The mere idea is daunting. But that’s what Enel Green Power has to do in countries like Chile or South Africa, where some of our largest photovoltaic fields are located.
Sand, debris, and simple dirt represent a serious problem for the functioning of panels and for the efficiency of entire plants. The more a solar farm is spread out or exposed to extreme conditions – like in deserts – the more its cleaning is a real daily challenge.
This is why, in Enel Green Power’s Solar Lab in Catania (Italy), where many of our innovations take shape, they thought of using “PV cleaning robots able to clean solar panels in a completely self-contained way, to be managed remotely”, explains Paola Pugliatti, innovative solutions specialist in the Solar Innovation Business Opportunities (IBO) of EGP.
Where did the idea of using these robots come from?
In complex places like Chile, we determined that traditional cleaning methods were not able to achieve the desired results, especially because of high levels of “dirtiness”. These are isolated, desert areas, where sand and dust are likely not only to decrease efficiency, but could also cause irreversible damage to the photovoltaic panels.
Why is sand so dangerous?
Because of the so-called soiling impact. Because of the dirt, solar radiation is not detected by the panel, which then fails to generate the right amount of energy. Plus, the partial shadow of some areas for long periods of time can cause breakdowns and malfunctions. Each geographic area presents different issues, and many depend on the weather and microclimate conditions of the environment where the plant is located. So coming to a completely automated solution for the cleaning of modules offers numerous advantages.
First of all, considerable recovery of energy produced by the panel, but also a precise programmability for O&M operations in the plants, as well as remote management that allows us to use the robots at any time and in any weather condition. Because they are programmable, the robots allow for a reduction of soiling impact by near to 90-100%. Furthermore, in addition to being very flexible, these machines are set up directly on the panel arrays: this prevents them from obstructing the spaces of the plant itself, like a worker or a cleaning vehicle would. Remember that every robot is completely stand-alone.
What does that mean?
That it functions completely independently. The robots are self-powered by batteries and photovoltaic panels, but above all, they don’t require water. This is crucial in desert areas, where water is scarce and where local governments apply severe restrictions on it.
Are further developments expected for the improvement of photovoltaic plan efficiency?
The robots’ constant work on the plants will allow us to gather very useful data, not only for improving their efficiency but also for broadening their activities. We imagine implementing sensors for more simplified monitoring operations. And in the future, we could have robots that clean panels while at the same time carrying out a “scan” to check the plant’s health status.
How are the initial experiments going?
We are working on pilot projects at our photovoltaic plain in Adrano, province of Catania, the historical site where Enel built the first concentrating solar plant in the world in 1981. In the Passo Martino Solar Lab, we are proceeding with more innovation tests. By March, we expect to have machines already in operation.