Energy production from fossil source
The production of energy from fossil sources is actually and in perspective very important, in account of the large availability of solid, liquid or gaseous fuels, the overall maturity of the technological solutions that can be used, the limited production cost. From the other side, this type of production must be evaluated with the limits of potential fuels exhaustion (or excessive increase of extraction costs and burdens), negative effect on the general problem of climate change, potential local impact.
The geographical distribution of potential energy sources is largely known, and also the conventional and innovative technologies that can be used to extract different types of fuel from natural environment are a fundamental aspect of assessment and verification of potentialities; the choices between gaseous (natural gas), liquid (oil), or solid (carbon) types of energy feedstock is based on original costs, capacity of extraction, but also effects on carbon balance in account of the emission.
The negative aspect of heavy impact of emitted carbon dioxide into the atmosphere, probably the most important environmental problem of today industrialized world, requires a strong attention to technological possibilities (increase in energetic efficiency, right choice of type of fuel, also consideration of perspectives of Carbon Capture and Storage), but also consideration of possibilities in term of financial tools (carbon tax, emission trading, cap and trade solutions).
With reference to technological solutions, the aspects of innovation in atmospheric emissions treatment, secondary destination or utilization of residual ashes, co-generation and increase in energetic efficiency are subject for strong attention from plant producers, and the literature, with a clear indication of Best Available Technologies for large production plants, is a very important source of information for the best choices about the future plants.
Fig. 5 – Example of a BAT solution for carbon energy plant
It is also important to consider the perspective of co-combustion : in fact in many industrialized areas there are important fluxes of residuals and solid wastes that must be properly disposed, and that are characterized by an important residual thermal value, leading to the possibility of energetic valorization. The objective to give a correct final destination to these wastes, and at the same time to substitute expensive external fuels, seems to be a very important possibility, obviously after careful consideration of absence of unacceptable environmental impacts. Besides to use in solid fuels thermo-electric plants, this perspective is very important for a positive adoption in cement kilns, in account of enormous capacity and convenient process conditions.
A last consideration in this type of exploitation is the perspective of urban micro-cogeneration; the possibility to obtain directly for the consumers electric energy and heat for household use, without cost of transport and with the best valorization of the produced energy, can be considered by sure a very interesting possibility; but a careful verification of aspects of environmental impact, in account of the difficulty to scale-down suitable technologies for emission treatment at the scale of very small micro-cogenerators, is for the moment a potential critical aspect.