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Water Distilled by the Power of the Sun Azuma Solar Co., Ltd. IP

Website: Azuma Solar Co., Ltd.external link
Category: Machinery

Azuma Solar is using more than 50 years of expertise with solar heaters to create clean drinking water

In developed countries, clean drinking water is hardly a concern. Yet amidst burgeoning populations and poor infrastructure, emerging countries struggle to ensure access to potable water. Azuma Solar Co., Ltd. has developed an efficient solar water heater that can also produce drinkable water.

Azuma Solar, in Kyushu’s Kumamoto Prefecture, started working with solar heaters in 1962 and now counts more than 50 years of experience. “We are serious about manufacturing good products," says President Seishi Higashi. "That is probably why we have lasted so long. In addition to the technology behind our hardware, the correct installation and handling of our systems is very important to us. Therefore, we are trying to do as much installation on our own and avoid OEM arrangements."


Azuma Solar Co., Ltd. President Seishi Higashi presenting his company’s innovative solar heating systems at their Kumamoto plant

The company has already proven itself in the field of manufacturing solar powered water heaters and solar floor heating. Unlike competitors that use high density polyethylene hot water storage tanks, Azuma Solar is the only manufacturer that opts for more durable stainless steel tanks. Up-front costs are higher, but Higashi points out that this saves money in the long term as high density polyethylene not only degrades over time due to UV radiation and extremes in temperature differences, but can release chemicals into the water – something undesirable for a solar water heating system.


Azuma Solar's system generates hot water as well as drinkable water

A Solar Heater that Distills Drinkable Water

That last point is key as Azuma Solar leveraged its years of experience in solar-powered water heaters to take their technology one step further – pioneering development of what they call a “potable water, simultaneous recovery solar water heating system.” This new system retains the basic principle of using solar power to heat water, but takes a simple yet clever approach to producing distilled, drinkable water simultaneously.

The system involves typical outdoor (and usually roof-mounted) heat collection panels, yet while a standard water heater just has one hot water tank, Azuma Solar’s solar water system has two. The first tank has two layers with cooling water in the outside layer. Hot water from the inner layer of the tank evaporates and condenses, running down the sides of the walls and pooling below in the evaporation catch. The energy generated from this process is used to heat the water in the upper hot water storage tank.

The distillation process kills off bacteria and provides safe, clean drinking water. “In an emergency, you could use water from a swimming pool or river,” adds Kenji Furukawa, PhD, a technical advisor to the company who is also a Professor Emeritus at Kumamoto University. Azuma Solar says their standard two-panel DSW-II unit can store 142 liters of hot water and has a distilled water capacity of 42 liters.

Patented Technology to Meet the World’s Water Needs

Azuma’s technology has already received patents in Japan, Germany, South Korea, China, Australia, Hong Kong and Israel, and is patent-pending in India, Indonesia, Thailand and Malaysia. Yet the company is focusing most on China, where, by Higashi’s estimate, nearly 1/3 of the world’s demand for clean drinking water can be found.

In the short term, the company plans to ship products from Japan to China, but Higashi says the import taxes, in addition to the shipping expenses, can end up doubling the cost. His goal is to partner with a manufacturer in China to produce these advanced solar water heating systems locally.

Azuma Solar believes their solar water system can not only bring clean water to developing countries but do it in a way that protects the environment as well.

Based on interview in February 2016


Azuma Solar’s solar water system creates distilled water that evaporates and cools, collecting in an evaporation catch, courtesy of Azuma Solar Co., Ltd.