Recent climatic data now confirms that the world has probably never experienced prolonged periods of climatic stability and we are now entering a period of global warming. Some countries ignore the fact that all fossil fuel resources have a finite life. Various forecasts dating back to the late nineteenth century have suggested that solar energy in its various applications could and should replace these conventional fuels as resource limitations begin to emerge. This paper follows from the author’s analysis presented at Porto in 2002 [1] and places world energy resources and environmental issues in their historical context. It reassesses an assumption that renewable energy sources could supply about 20% of the world energy requirement by 2020, taking into account environmental, technical and economic factors. Other recent future energy projections have been examined using a modified S-curve [logistic] approach linked to the Volterra-Lotka equations. Energy and environmental issues in China were stressed in the 2002 paper. Many of the 10 new EU Accession States hope to follow the path of Ireland’s recent economic success - the “Celtic Tiger” phenomenon. The Chinese Premier, H.E. Mr Wen Jiabao, has made similar comments. But Ireland’s current energy policies are quite unsustainable. A future with the substantially reduced levels of greenhouse gas emissions suggested to the world by the Intergovernmental Panel on Climate Change [IPCC], will very difficult if not impossible to achieve. Problems with inconsistent energy and economic data are noted.