Energy and Electricity - Introduction to Carbon Capture and Sequestration - page 24

Table 1.4.1 CO 2 concentration in flue gasses and air

Gas CO 2 Concentrations

Air 380-580 ppm

Natural Gas 5-8%

Coal 10-15%

happening throughout the USA, owing to the glut of natural gas obtained
from hydraulic fracturing and drilling technologies.
One expects, therefore, that phasing out coal-fired power plants and
replacing them with natural gas-fired power plants will be an important
contribution to the reduction of greenhouse gasses .
Such schemes confront an economic reality. The average lifetime of
a coal-fired power plant can be as much as 50 years and the investment
outlay is on the order of $2 billion for a new 600 MW coal-fired power
plant [1.13]. Electricity companies will be very reluctant to write off such
an investment, so we most likely have to accept that it is only economi-
cally feasible to replace the very old and inefficient coal-fired power
plants with natural gas plants (see Section 1.2).