Solar system costs have declined by 27 per cent over the past three years.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/rooftop-solar-systems-could-help-reduce-power-bills-study
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/indian-express-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/solar-energy
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/renewable-energy
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/power-transmission
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy-policy
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy