Solar power plant

Section 80 IA of the Income Tax Act exempts solar energy companies from tax on 100% profits for the first ten assessment years. This perhaps applies only to plants commissioned before 31st March 2017.

     Why this exemption was limited to plants commissioned only before 31-3-2017? Why was that also repealed? Were any changes made to the Act which could provide equivalent exemptions? Is there any way I could get full exemption?

  My enterprise is registered under MSME. What tax exemptions can I avail?