Modelling the Evolutionary Paths of Multiple Carbon-Free Energy Technologies with Policy Incentives

In this paper, we establish an economy-energy-environment integrated model by introducing a new technical mechanism, that is, the revised logistic model, to be the technical core of the energy module. This gives the conventional top-down modes more bottom-up features and allows us to model the evolutionary pathways of multiple non-carbon technologies. The model's simulations indicate that the mixed policy of both carbon tax and subsidy plays a significant part in promoting the development of new energy technologies. The shares in total primary energy usage for PV solar, geothermal power and wind energy, for example, will have increased to 24.9, 9.7 and 6.12 %, respectively. Meanwhile, technological progress can be significantly enhanced by introducing research and development (R&D) investment. As a result, the percentages of usage of the above three technologies are likely to increase to 26.2, 12.1 and 7.2 %, respectively, in that case. Besides, energy supply market will be locked up by non-fossil energy as early as 2035, or thereabouts, under the current R&D investment regime. Thus, the expansion of R&D may significantly improve the carbon-reducing potential of the mixed policy and perform well in easing the tax burden on businesses and consumers in the long run.