The German solar company has been commissioned as an engineering, procurement and construction contractor by solarcomplex AG to build the park in Bodman-Ludwigshafen.
According to Phoenix, the project will be installed across around 800 metres of land on both sides of the railway tracks from Stockach to Radolfzell. It is expected to be completed by the end of August.
In a statement, the company said: "Since the summer of 2010, only ground-mounted photovoltaic plants on sites already sealed or conversion sites or within a 110-metre corridor along motorways or railway tracks are eligible for promotion under the German Renewable Energies Act."
Overall, more than 58,500 First Solar modules and inverters from SMA will be used in the plants construction. When complete, it should generate around 4.9 million kilowatt hours of energy annually.
Commenting, Ralph Schneider, executive vice president of solar energy investments of Phoenix Solar said that the company will be turning its focus to projects in Germany for the rest of 2011, having worked on projects internationally for the first half of the year.
Phoenix Solar and solarcomplex have been working together since 2005.