Another 2.5 MWp will be added to the existing solar capacity of 4.1 MWp which is expected to be completed by February 2020.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/chennai-metro-rail-limited-increases-its-total-solar-capacity-41-mw
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/new-indian-express-chennai
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/tamil-nadu
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/solar-energy
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/renewable-energy
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/green-buildings
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy