Hanwha SolarOne has delivered PV modules to a 3 MWp solar park owned by the city of Offenbach, in Hessen, Germany. This large-scale project was constructed on the steep hillside of a former landfill, which presented a series of challenges for developer Rhein-Main Deponienachsorge GmbH (RMN) before connecting to the grid in April 2013.
“Political will and technical competence were crucial in identifying a future-oriented solution for this problematic site. The city of Offenbach and RMN have proven both, and the result is really impressive,” said Anke Johannes, Sales Director, Germany at Hanwha SolarOne GmbH. “We congratulate the Offenbach residents on the new PV park, the area’s largest to date. This is a great example of how public players like municipalities can turn challenging areas into profitable and environmentally-friendly projects. At Hanwha SolarOne, we look forward to contributing to more projects like this in the future.”
Troublesome Past, Bright Future
In the early 1960s, Offenbach ended the activity in the 25 year-old lime rock quarry known as "Schneckenberg". Over the following decades, the former quarry was filled with millions of tons of industrial and household waste, causing serious pollution in the area. Eventually reaching 166 meters above sea level, Schneckenberg became the highest point in Offenbach.
Throughout the extensive 10-year decontamination process, which ended only a few years ago, the ground was sealed through a capillary barrier that stops rainwater from trickling through accumulated waste and into the groundwater. Despite these thorough efforts, the area’s potentially hazardous groundwater and gases must still be monitored for years to come.
After finalizing the site’s transformation, various options for future land use were explored, but mostly not considered feasible. For example, the site could not be used as a recreational park until the completion of the aftercare phase, nor could it be used for a wind park because its soil is only 50 centimeters deep.
When RMN first proposed constructing a solar park on the south side of the hill, Offenbach’s regional council was skeptical; although the area’s capillary barrier is strong, it had not been constructed to hold additional weight. After proving that a solar park would not affect sealing system operations, RMN was awarded approval from the city council.
Remediation company Rhein-Main Deponienachsorge GmbH (RMN) is specialized in the sustainable and safe termination of landfills and currently operates the Offenbach park. Sinusstrom GmbH was responsible for the PV park’s planning and construction.
“We’ve truly benefited from Hanwha SolarOne’s broad experience with large-scale PV installations," said Markus Töpfer, CEO of RMN. “Moreover, the company’s flexibility and timely deliveries largely contributed to the success of this project.”
The solar park, which features 12,832 polycrystalline modules from Hanwha SolarOne, connected to the grid in April 2013. With an estimated annual energy production of 2.8 million kilowatt-hours, the park can cover the electrical demands of about 1,100 German households. The new 3.7 hectare solar installation in Offenbach can be seen when approaching Frankfurt by air.