Danish shoe producer ECCO runs the largest solar thermal installation in Thailand: 1,890 m² of vacuum tube collectors provide the company’s factory in Ayutthaya with up to 80 tons of hot water per day. Planned and installed by German engineering company Aschoff Solar, the process heat installation supplies the different tanning processes with water at temperatures between 35 and 70°C. The photo shows the three stackable containers, including the ready-to-use tanks, pump groups and heat exchangers prefabricated in Germany. The system offers a solar controller with graphical display and online remote control.
The installation is based on a closed-looped non-pressurised solar circuit filled with water, as is common for plants by Aschoff Solar. “The collector field is our design. Clamping the vacuum tube collectors and the support system together eliminates the need for holes on the roof,” explains Carsten Aschoff, Managing Director of Aschoff Solar. The engineer estimates a solar yield of 900 kWh/m² based on the results of the tannery installation at the Sadesa leather factory in the neighbouring town of Sena. Aschoff installed the 540 m² system in 2011.
1,890 m² of vacuum tube collectors on the roof of the ECCO tannery in Ayutthaya, Thailand
Photo: Aschoff Solar
The Department of Alternative Energy Development and Efficiency (DEDE) has subsidised one fourth of the total cost of the ECCO plant. DEDE projects are limited to 2,000 m², so the shoe producer plans to extend the installation to 2,500 m² during Phase 2 of DEDE’s support programme next year. With the extension, the solar installation will provide 70 % of the tannery’s total energy demand. A gas boiler serves as the backup source.
Two years of marketing and sales activities of Aschoff Solar have led to the new successful showcase at ECCO. “We exhibited at Lineapelle over the last two years, the leather fair in Bologna, Italy, and we are member of the Leather Working Group, a network of tanneries aiming to implement a common eco label,” says Aschoff. ECCO plans to also equip its other tanneries in China, Indonesia and the Netherlands with solar thermal technology.
According to Aschoff, solar thermal still faces a number of challenges in Thailand, such as high competition of biomass, a lack of trust in the technology and a low level of environmental awareness. His recommendation: prefabricate most parts, install a monitoring system and thoroughly check any installation. Technicians in Thailand had fairly little skills in setting up solar technology and their working morale was rather low.
The text was written by solar thermal specialist Yaping Zhang, solrico partner in China.