A look at freshwater usage in solar manufacturing

With solar power becoming more economical, quick to deploy and zero-emissions, it’s quickly emerged as a winner in the energy transition. As a result, countries all over the world are moving to boost their solar supply chains, including attracting manufacturers with subsidies and other incentives. Yet, as the race for solar domination intensifies, manufacturers are increasingly coming face-to-face with a new problem — the need to efficiently manage and conserve freshwater resources to protect local communities, the environment and their bottom line.

It’s an issue that’s gaining mainstream prominence, and as the world’s freshwater resources continue to dwindle, water-intensive industries like solar PV manufacturing are undergoing greater scrutiny. Much to their benefit, however, manufacturers now have access to the up- and downstream water management processes and technologies needed to integrate water conservation directly into their facilities, giving them a way to reduce environmental impacts, lower operational costs and future-proof operations from potential uptake limitations.

Solar manufacturing and water scarcity intensify

The story of solar PV manufacturing is one of remarkable success and abundance, with annual manufacturing capacity on track to hit more than 1,000 GW in 2024. Currently, over 80% of all polysilicon, wafer, cell and module development occurs in China, although the market is rapidly diversifying into Western Europe, North America, South Asia, Africa and the Middle East. While many countries are undergoing an industrial renaissance thanks to solar PV manufacturing, they’re also facing an imminent water crisis.

By 2030, the demand for fresh water is expected to outstrip supply by nearly 40%, with misplaced subsidies and industrial growth being two of the leading causes. At the same time, 2023 was just named the hottest year on record, putting further pressure on freshwater availability — a trend that is only expected to worsen. Solar manufacturers require fresh water specifically as it contains little dissolved minerals, which reduces the risk of mineral deposits or corrosion that could affect the efficiency and manufacturing yield of their products. Yet, only half of 1% of the world’s water supply is accessible as fresh water, underscoring the importance of preserving it.

The importance of water conservation

Embracing water conservation simply makes sense, as industrial consumption is usually first to be curtailed when water shortages strike. For solar manufacturers that are bound by inefficient water uptake and treatment processes, forced downtime could be financially devastating, making proactivity important.

Manufacturers rely on water for a range of purposes, including cleaning, cooling, etching and processing crystalline and thin-film solar panels. Large gigafactories can use millions of gallons every day, and at the same time, produce substantial volumes of wastewater. Cleaning and etching solar PV systems, which are key to enhancing solar cell efficiency, generate reverse osmosis ion exchange regeneration concentrate wastes. Producing solar PV electrical contacts and wiring also creates wastewater, as significant amounts of purifying solvents like nitric or hydrochloric acid need to be used. The resulting wastewater is highly toxic and requires treatment before it can be reused or released safely back into the environment, making water recycling and purification for secondary and tertiary purposes critical. Not only does conservation significantly reduce overall water intake — thereby protecting local communities and the environment — but it also saves manufacturers money in the process.

As one of the critical necessities for life on Earth, fresh water demands careful management, especially by heavy industrial users like solar manufacturers. Maximizing water conservation and reducing necessary discharges will ultimately benefit companies, allowing them to avoid regulatory restrictions and ensure reliable production that can meet the demands of today’s ambitious developers.

Having the right equipment and systems in place to manage water effectively can make a world of difference to manufacturers’ resilience, profitability and corporate sustainability. The time is now for the solar sector to embrace water conservation.