| dc.description.abstract | From the pre-industrial period till now fossil fuel has played an important role for fulfilling the demand of energy for cooking and heating. At present about 40% of global electricity is being produced by burning different quality and type of coal and this is predicted to increase by 5% in 2030. Coal contains a high amount of carbon and emits large quantities of carbon dioxide into the atmosphere during combustion. It is predicted that burning fossil fuel alone for generating electricity is emitting about 25.9% of carbon dioxide into the atmosphere. Atmospheric concentration of carbon dioxide and other greenhouse gases has increased from pre-industrial level, leading to a global temperature increase of 0.7 degree centigrade.
Coal being highly rich in carbon content compared to other fossil fuels such as natural gas and petroleum, emits relatively higher carbon dioxide into the atmosphere. According to IEA, coal and gas comprised of 41.5% and 20.9% of electricity generated worldwide. There are different ways of generating electricity using coal and gas such as converting coal into fine powder or into gaseous form before combustion. In the case of gas fired power plants combined cycle power plant is regarded as a more efficient method of generating electricity as waste heat is also re-utilised to generate electricity. In comparison between coal and gas, gas is regarded as less carbon intensive fuel, emitting 55% less CO2 per MWh of energy produced.
Many non-carbon technologies are already in commercial use to reduce emissions from industries and power plants to atmosphere. One of the alternatives is switching from carbon to non-carbon sources of energy such as solar, wind, hydro and nuclear powers or to less carbon intensive sources of energy. However, switching to non-carbon sources of energy is not easy for all countries globally. Therefore one of the possibilities would be to implement new technology in power plants called Carbon Capture and Storage technology. With Carbon Capture and Storage technology it is possible to capture 80-90% of carbon dioxide from the power plants.
In this thesis, I have compared the cost of Carbon Capture and Storage (CCS) using different fossil fuel power plants for generating the power. Three types of power plants, Pulverized coal (PC), Intergraded gasification combined cycle (IGCC) and Natural gas combined cycle (NGCC), are considered when analysing the cost of electricity with and without the carbon capture facility installed. Cost comparisons between renewable and CCS implemented plant is also discussed.
Using Carbon Capture and Storage Technology reduces the net efficiency of power plants and increases the cost per unit of power production. Analysis and comparison shows that with and without capture technology installed, pulverized coal plant emitted higher carbon dioxide compared to natural gas power plant. Without capture facility installed 78.29 US$/MWh of electricity produced by a PC plant was found to be cheaper compared to 89, 81 US$/ MWh by NGCC power plant. At the same it was also found that with capture facility installed cost of electricity increased by 47.01 US$/MWh for PC plant, 28.04 US$/MWh for IGCC plant and 68.88 US$/MWh for NGCC plant, with capturing efficiency of approximately 90% .
Transportation and storage also play an important role in per unit cost of the power produced. Review of the literature showed that transportation costs for same distances varied with capacity of the power plant, the higher the capacity lower the cost.
Further a simple optimisation model is presented to analyse the optimal path of Carbon Capture and Storage technology compared to plants without carbon capture and renewable energy. Four phases of the model are discussed and the outcome starts in phase I and moves to phase II or starts directly from phase II if tax rates on carbon dioxide are sufficiently high. As a result the outcome will asymptotically approach phase III if s'(v)=0 and phase IV if s'(v)>0.
Cost of fossil fuel power with CCS technology is compared with hydro power, nuclear energy, solar energy and wind energy. The comparison showed that the cost of electricity production is lower for non carbon emitting power plants compared to capture power plants.
Finally, the marginal cost of electricity production is calculated with different levels of tax rates. From the results it can be seen that with substantially high emission penalties CCS technology would become competitive in the market with plants without capture. However, with abundant availability of fossil fuels and large scale deployment of CCS technology a fraction of total carbon dioxide produced during electricity production will still be released back into the atmosphere. | eng |