The technology - called supercritical, an advance over the previous generation subcritical - is among the best available for coal-fired power generation and is widely used in the US, Germany, Japan and China. But detailed daily CO2 emissions data are available only for the US and they show that many of them emit more greenhouse gases than its earlier variants, even those going back to the 1970s.
"Empirical evidence of cleaner technology credentials is hard to come by for the supercritical power plants touted by the WBG (World Bank Group)," said a US-based environmental research group CO2Scorecard in a recent report.
"(Forty)-year-old plants frequently outperform their new, highly-promoted counterparts," the report added.
The report has been actively shared since publication.
World Bank Group's International Finance Corporation (IFC) is part funding this project which is wholly owned by Tata Power.
The company will be using coal imported from Indonesia in the initial phases.
India generates 94,653 mw power from coal, and 174,361 mw total.
Tata Power did not respond to an email. The IFC did.
"The greenhouse gas emissions per kilowatt hour of energy generated by the plant were estimated at 0.75 tonnes of carbon dioxide per mw hour (750 grams per KWh), which is significantly less than India's national average of 1.25 tonnes carbon dioxide per MWh for coal-based power plants," said an IFC spokesperson.
In short, it's much better than what India has. And it should feel blessed.
"But India's average for CO2 intensity is abysmal and that's not an acceptable standard for justifying IFC's world class power plant investment," said Kendyl Salcito of the CO2 Scorecard initiative.
Even in the US, power plants using supercritical technology were found by CO2Scorecard generating between 0.87 tonnes of CO2 and 1.12 tonne per MWh.
The newest of them, IATAN U-2, averaged 0.91 tonnes for every MW hour of electricity, more than 20% higher than what IFC has promised for Tata Mundra.
But the research group is not demanding that the plant be junked. "If Tata Mundra and IFC can show that the project generates 0.75 tonnes of CO2 for every MWh of electricity, it will be cleaner than the cleanest coal power plant in the US," said Shakeb Afsah, co-author of the CO2Scorecard report.
If the plant fails to meet IFC's CO2 intensity target of 0.75 tonne per MWh by even 5-10%, it would add an estimated $20-35 million worth of CO2 to the atmosphere annually. The entire project is worth around $4.2 billion.
Source- Hindustan Times