How to Reduce Carbon Dioxide Emissions from Power Plants

As per the Kyoto protocol, developed nations, the largest producers of Green House Gases (GHG), agreed to reduce GHG emissions by 5.2% of 1990 levels by the year 2010. This in effect is an almost 29% reduction in GHG considering capacity additions and developments till 2010.

The very essence of energy release from fossil fuels is the exothermic chemical reaction of Carbon and Oxygen to form Carbon dioxide. CO₂ is an inevitable outcome of the process. So if we have to reduce CO₂ we have to either stop burning Carbon or burn Carbon more efficiently.

• The immediate recourse is to operate power plants at the best efficiency to reduce fuel input per unit of energy.
• The next is to invest in technologies that improve the level of efficiency in coal fired thermal power plants from the current 35% level to the 50% level. Use of the combined cycle in coal fired power plants by coal gasification is one technology that is promising to improve power plant efficiencies.
• Converting gas turbines in the open cycle mode to the combined cycle mode increases plant efficiency.
• The real reduction in emissions can come only by drastically changing the energy generation mix. From the predominantly fossil fuelled energy mix today we have to go to a nuclear and renewable energy mix. More of wind and solar powered plants together with nuclear plants are the only reasonable and cheaper solutions for energy with reduced emissions.

Considerable investments in plant and technology together with social and political will are essential for this changeover.

One method is to capture the CO₂ before it reaches the atmosphere. This is easier said than done. The method involves the separation of CO₂ from the flue gases, piping and storing them in underground or under sea cavities. Many pilot projects of this Carbon Capture and Storage Systems (CCS) are on the anvil.

This is the reverse of what we are doing today. In this system we store the CO₂ deep under earth from where we took the fossil fuels.

This Carbon sequestration is a costly process, and we have to wait and see how much society will be willing to pay extra for it.

The other method is to offset higher CO₂ emission with lower CO₂ emissions in other projects locally or in other countries. This is piggy back riding on those producing less CO₂.

The method tries to take into account the global concentration of CO₂ instead of individual or localized emission concentrations. The Clean Development Mechanism of the Kyoto Protocol allows countries with an emission-reduction or emission-limitation commitment to implement emission reduction projects in developing countries. These projects should have additional reductions in CO₂ emissions than would have been normally possible.

The Certified Emission reductions from these projects are saleable as Carbon Credits. These Carbon credits are used to offset the increased emissions of CO₂ and other greenhouse gases produced in the developed countries.

Buying and selling of Carbon credits have evolved as a billion dollar market.

By these and other methods we hope to see much reduced CO2 emissions by the year 2012 and beyond.