This dissertation examines the potential impacts of three electricity policies on the economy of Thailand in terms of macroeconomic performance, income distribution, and unemployment rate. The three considered policies feature responses to potential disruption of imported natural gas used in electricity generation, alternative combinations (portfolios) of fuel feedstock for electricity generation, and increases in investment and local electricity consumption. The evaluation employs Computable General Equilibrium (CGE) approach with the extension of electricity generation and transmission module to simulate the counterfactual scenario for each policy. The dissertation consists of five chapters. Chapter one begins with a discussion of Thailand's economic condition and is followed by a discussion of the current state of electricity generation and consumption and current issues in power generation. The security of imported natural gas in power generation is then briefly discussed. The persistence of imported natural gas disruption has always caused trouble to the country, however, the economic consequences of this disruption have not yet been evaluated. The current portfolio of power generation and the concerns it raises are then presented. The current portfolio of power generation is heavily reliant upon natural gas and so needs to be diversified. Lastly, the anticipated increase in investment and electricity consumption as a consequence of regional integration is discussed. Chapter two introduces the CGE model, its background and limitations. Chapter three reviews relevant literature of the CGE method and its application in electricity policies. In addition, the submodule characterizing the network of electricity generation and distribution and the method of its integration with the CGE model are explained. Chapter four presents the findings of the policy simulations. The first simulation illustrates the consequences of responses to disruptions in natural gas imports. The results indicate that the induced response to a complete reduction in natural gas imports would cause RGDP to drop by almost 0.1%. The second set of simulations examines alternative portfolios of power generation. Simulation results indicate that promoting hydro power would be the most economical solution; although the associated mix of power generation would have some adverse effects on RGDP. Consequently, the second best alternative, in which domestic natural gas dominates the portfolio, is recommended. The last simulation suggests that two power plants, South Bangkok and Siam Energy, should be upgraded to cope with an expected 30% spike in power consumption due to an anticipated increase in regional trade and domestic investment. Chapter five concludes the dissertation and suggests possibilities for future research.