5.2. WTE challenges
Many WTE technologies are designed to handle only a few types of waste (biomass, solid waste, and so forth).
Completely separating different types of waste can be tremendously difficult. Determining the exact composition of a waste
source can be nearly impossible. WTE technologies must either become more versatile or be supplemented by material
handling and sorting systems if they are to be successful. They are many WTE challenges (e.g., waste-gas cleanup,
conversion efficiency, regulatory hurdles, and high capital costs). The gas generated by various processes (e.g., pyrolysis and
thermal gasification) must be cleaned of tars and particulates before clean, efficient fuel can be produced. A number of WTE
pilot plants, particularly those using energy-intensive techniques (e.g., plasma), have functioned with low efficiency. Toxic
materials include both trace metals (e.g., lead, cadmium, and mercury) and trace organics (e.g., dioxins and furans).
Such toxins pose an environmental problem if they are released into the air, dispersed into the soil, allowed to migrate into
ground water supplies, or make their way into the food chain. The control of such toxins and air pollution is a key feature of
environmental regulations governing MSW-fueled electric generation. The regulatory climate for WTE technologies can be
extremely complex. These regulations may prohibit a particular method (typically incineration) due to air-quality concerns.
Although changes in the power industry have allowed small producers to compete with established power utilities in many
areas, the electrical grid is still protected by yet more regulations. These regulations pose as obstacles to would-be wasteenergy
producers. WTE systems are often quite expensive to install. Despite the financial benefits they promise, the high
installation cost is a major hurdle, particularly for new technologies that are not widely established in the market. Fig. 5
illustrates possible fossil fuel and hydrogen prices up to the year 2015. This image suggests that although fossil fuel prices
are predicted to increase, hydrogen prices are predicted to decrease. By 2018 these price will cross each other at the $10 GJ-1
range. However, because hydrogen has a higher utilization efficiency (η¼1.35), hydrogen prices will be competitive with
those of fossil fuels by approximately 2015.