In simple terms, wood-fired stoves, barbeques, or wa­ter heaters are a biomass-based renewable energy system. Yet, the growing range of new medium- to large-scale bioenergy technologies include gasifier and pyrolysis power stations coproducing electricity, heat, and a range of biofuels. Nonetheless, all traditional and new technol­ogies convert the complex hydrocarbon molecules in biomass to hydrogen, methane, carbon monoxide, carbon dioxide, and numerous other gasses, including polyaro­matic hydrocarbons and dioxins. Some technologies also produce liquid and soil fuels (such as biochar) from the same biomass. In general, while small-scale and simple technology designs have less control and efficiency, they exhibit lower capital and operating costs, although they are usually more labor intensive per unit production of output (McHenry, 2012b). At the regional scale biomass power plant technology choices often

include gasifiers (which optimize gas production), and slow pyrolysers (which optimize biochar production). A general outline of the variations in biomass renewable energy technologies are shown in Table 26.2. In terms of developing a regional energy/biochar industry, medium-sized biochar production units may address concerns of soil nutrient loss from harvested biomass. Despite the generally high costs of transporting timber trees, transporting returned biochar is relatively efficient on a weight basis, as the biochar mass is 70—80% less than the original dry biomass (Lehmann, 2007). Nonetheless, industrial biochar production and use will require a number of safeguards. Handling risks include flamma­bility concerns, and the dusts can spontaneously combust in enclosed spaces and is comparable to the risk of handling some metals, foods (flour, etc.), coal, plastics, and woods (Joseph, 2007).