POWER SECTOR – GREENHOUSE GAS EMISSIONS

Power Sector is the single biggest contributor to greenhouse gas inventory (GHGI), which is primarily responsible for Global Warming. Total contribution to GHGI from each of the electricity generating technology - emissions from the production of raw materials (like steel, aluminum, etc) to the various process stages of generation of electricity, including management of waste and transmission of the power, need to be taken into account to get the Full Energy Chain Greenhouse Gas Emission Factor (FENCH-GHG) in the units of carbon dioxide equivalent per kilowatt hour electric, for the purpose of comparison. The results of one such Japanese study is given below:


More effective (than CO2) GHG methane emitted from the decaying water-submerged vegetation is not taken into account in the above calculations for hydropower sector. Hence, probably the factor is low. As could be seen nuclear power is the environmentally cleaner power option. Then what is stopping?

GREENHOUSE EMISSION FACTORS FOR SOME MATERIALS

For Full-Energy-Chain (FENCH) analysis is required for comparison of different energy options in power sector with respect to greenhouse gas emissions to facilitate energy planning and taking policy decisions. The greenhouse gas emission factors (GHEFs) of the raw materials flowing into the different energy sources at different stages such as construction (steel &cement) and selection of materials for the equipments (steel, aluminum, copper), are also important to calculate the overall greenhouse gas emissions, including non-CO2 emissions such as CF4, N2O, etc). The GHEFs (IAEA data) in the units of gm CO2 equivalent per gm of some of the greenhouse gas intensive materials are given here:

Cement : 0.76
Concrete : 1.95
Steel : 2.2
Aluminum : 34.2
Copper : 3.5
Silicon : 181
Glass : 1.2
Nitric acid : 1.4
Plastics : 7.9

As could be seen, silicon and glass (used in solar energy system) are highly GHG intensive material. Similarly, aluminum is extensively used in nuclear energy. GHG emissions control should start right from Cradle to Grave, i.e., Full Energy Chain.