PROJECT DETAILS

Brief Description
 

The world is moving towards a solar economy, but cleaning solar panels consumes significant amounts of freshwater, annually between 3 and 5 million liters (3 000 – 5 000 cubic meters) for each megawatt of nominal power. In the beginning of 2026 the world’s combined photovoltaic production was still only 3 terawatts, meaning 3 000 gigawatts or 3 000 000 megawatts, but this is expected to rise to at least 100 terawatts during this century.

Cleaning 100 terawatts of solar panels in the present way would then consume between 300 and 500 cubic kilometers of water, meaning up to 12 per cent of humanity’s current use of freshwater.

The humanity’s direct freshwater consumption at the moment is about 4 300 cubic kilometers of which 2800 km3 is by agriculture, 900 cubic km3 by industry and energy production and 500 km3 by cities, municipalities and households. (If also the evaporation from dams and irrigation canals is counted, the calculated global freshwater consumption rises to 9 100 – 10 300 cubic kilometers.)

Cleaning the photovoltaic panels is important, because in areas with heavy dust, ash and soot fall, the power production of photovoltaic panels can drop, in arelatively short period of time, by more than 50 per cent without reqular cleaning.

The same problem also exists with thermal solar collectors and so called PVT panels, producing both heat and electricity. InSIC has supported a project of Kolkata University that tries to solve the problem with a novel electro-dynamic cleaning system, but it has not started to spread in a large scale, yet.

This InSIC-funded project, implemented by NB Institute for Rural Technology (NBIRT) and led by professor S.P. Gonchaudhuri and Dr Richik Ghosh Thakur, aims at mitigating the problem by developing a system of cleaning and reusing the water used in the cleaning of the solar panels. If the same water can used several times, the pressure on scarce water resources will be much less. It is not necessary to remove soap from the water used in the cleaning, because according to some trials mixing soap in the water well before the cleaning is done is another way of reducing the consumption of water.

 

Project budget: 3500 euros