It depends on the size of the plant. Usually 1 to 1.5 years is the time for a plant to obtain EC after filing of Application. The following are the time-bound activities according to the EIA Notification: 
1) Issuance of ToR: To be issued within 60 days of Application submission by Project
Proponent. 
2) Conducting of Public Hearing: The Public Hearing Report to be submitted to the MoEF/ SEIAA by the SPCB within 45 days of receiving request for hearing from the Project Proponent. 
3) Issuance of EC: To be issued within 105 days of the Project Proponent submitting the
Final EIA.

CEPI is a number to characterize the environmental quality at a given location. CEPI scores are calculated from time-to-time by the CPCB to identify critically polluted areas and industrial clusters, by monitoring their air, land and water. CEPI Score is an important tool to identify those clusters where industrial development activities have been restricted due to their pollution levels. In 2010, the MoEF imposed a moratorium on the consideration of projects for EC, if they were located in 43 critically polluted areas. It has been reduced to 7 clusters as of September 2013. TPPs cannot be located in those places where the moratorium is imposed.

Situating a plant along the coast provides two important benefits to the Project Proponent:
1) Easy transport of imported coal through ports and captive jetties.
2) Easy availability of seawater for on-site seawater desalination technology for both once-through cooling and for boiler-feed water generation. This reduces fresh water requirement for running the thermal power plant.

The Ministry of Environment & Forests (MoEF) has classified TPPs as one of the 17 Red Category industries. Red Category denotes heavily polluting industry. For obtaining EC:
Category A projects are: 
1) > 500 MW Coal/Lignite/Naphtha & Gas Based Fuel.
2) > 50 MW Petcoke, Diesel and all Other Fuels, including Refinery Residual Oil Waste (excluding Biomass).
3) > 20 MW Biomass Based or Non-Hazardous MSW (Municipal Solid Waste) as Fuel.

Category B projects are -
1) < 500 MW Coal/Lignite/Naphtha & Gas Based Fuel.
2) <50 MW or 3 MW Petcoke, Diesel and all Other Fuels, including Refinery Residual Oil Waste (excluding Biomass).
3) < 20 MW or 15MW Biomass Based or Non-Hazardous MSW (Municipal Solid Waste) as Fuel.

The National Mission for Enhanced Energy Efficiency (NMEEE) is one of the eight missions under the National Action Plan on Climate Change (NAPCC). NMEEE aims to strengthen the market for energy efficiency by creating conducive regulatory and policy regime and has envisaged fostering innovative and sustainable business models to the energy efficiency sector. The Cabinet had approved the NMEEE document, and funding for two years of the 11th Plan period (2010-12) with an outlay of $ 36.23 million. Continuation of NMEEE for the 12th Plan was approved by Cabinet on 6th August, 2014 with a total outlay of $ 119.23. The Mission seeks to upscale the efforts to unlock the market for energy efficiency which is estimated to be around $ 11.385 billion. The activities during the 11th Plan period created the institutional and regulatory infrastructure. The NMEEE spelt out four initiatives to enhance energy efficiency in energy intensive industries which are as follows:
a) Perform, Achieve and Trade Scheme (PAT), a market based mechanism to enhance the cost effectiveness in improving the Energy Efficiency in Energy Intensive industries through certification of energy saving which can be traded.
b) Market Transformation for Energy Efficiency (MTEE), for accelerating the shift to energy efficient appliances in designated sectors through innovative measures to make the products more affordable.
c) Energy Efficiency Financing Platform (EEFP), for creation of mechanisms that would help finance demand side management programmes in all sectors by capturing future energy savings.
d) Framework for Energy Efficient Economic Development (FEEED), for development of fiscal instruments to promote energy efficiency.