Petronet LNG is one of the safest midcap stock with big potential.  Company has market cap of 5700 Cr and earnings of 450 Cr.  Selling at p/e of 11. Little expensive for LNG company.  Petrochemical companies usually sell of low p/e around 6-7, due to high capital requirement and high debt in balance sheet.

Looking at future Energy and LNG demand will continue to rise.It's Dahej Terminal has capacity of 2 MMTPA while coacin terminal still under construction will be having capacity of 2.5 MMTPA. That should double the revenue and hence profits . Demand for gas will not be an issue.  The biggest risk going forward is getting supplies in spot market.

LNG tieing up gas supply from long term contracts, where it get competitive pricing in range of 4-5$ per BTU compared to 17-18$ in spot market.

Will it be able to maintain margin ? I think so .  In next 5 year I see this company revenue going to 20000 cr from existing 6000 cr.  and earning of Rs25-30 per share. That should give it a price of more than 300 comfortably.

Now on side node, petro is cyclic industry . Company's profitabilty will change according to indystry cycle, that's exactly reason I usually don't like cyclic stocks for more that few years.  If one is looking for 5 years, they should go for FMCG like Marico , Nestle etc.