ABSTRACT
Biomass refers to material from living or recently living organisms, especially from plants, which is usually employed as an energy source, either burned to produce heat or converted to biofuel. Numerous plants are capable of generating considerable biomass, and C. sativa is one of them (Poiša et al. 2010; Figure 10.1). Concern over rising prices and ecological damage associated with the use of petrochemicals has led to attempts to reduce fossil fuel use by substituting biomass plants to produce energy. Most biomass is currently derived from wood, but as discussed in Chapter 16, dealing with sustainability, trees are a diminishing resource, and crops are being considered as new sources of biomass. Hempseed-based biodiesel is discussed in Chapter 8. Biodiesel is usually produced from edible oilseed crops (such as rapeseed) and bioethanol is usually manufactured from edible carbohydrate crops (such as maize and sugar cane). This is controversial, since using cropland to produce biomass instead of food can reduce the availability and increase the cost of food, especially in low-income nations. It has been argued that using crops that produce only inedible “lignocellulosic biomass” (such as fiber hemp) avoids the ethical problem, but it does not, since the land could be used for food production (including oilseed hemp). Rehman et al. (2013) explored the possibility of using harvested wild-growing hemp in Pakistan as a source of biomass, which certainly would be an ethical strategy. As discussed in Chapter 16, C. sativa is an especially sustainable, environmentally friendly plant, and so when grown as a crop for whatever purpose, possibly including biomass production, it is relatively benign to the planet and to people. Compared to other crops grown for energy, hemp is considered to be a reasonably efficient source (Finnan and Styles 2013).
