Our objective is to foster the understanding of the economic impact on environment. We apply SD modelling methodology and conduct our simulation. We investigate major trends of global threats: deteriorating environment and depletion of non-renewable resources. We list the important and causal relationships among the levels and trace the feedback loop structures. In describing an economic and environmental model we focus on the relationship among income, pollution, and non-renewable. This paper yields insight into the possibilities for replacing non- renewable fossil fuels with more renewable ones. Next, we present the simulation runs of the model, conducted with the help of existing system dynamics modelling tools.