Conversion Technologies 71
than those of the corresponding conventional ones due to more complex methods of
extraction. Currently known technologies of extracting non-conventional resources
rely on utilisation of significant inputs of energy and water and come with risks of sig-
nificant methane emissions. Especially water is a matter of concern; water is becoming
a scarce resource in numerous locations and its expanded use of non-conventional
fossil resources may additionally worsen current strain on the freshwater resources and
result in the complete destruction of unique ecosystems of Canadian tundra, Orinoko
River Delta and many others. Additionally, many of non-conventional technologies rely
on aggressive methods that can seriously impact ecosystems like strip mining.
To summarise, there are fossil-based alternatives to renewable sources of energy and
carbon, but their large exploitation is likely to aggravate climate change issues more
than those of conventional resources; therefore a sensible path to developing low carbon
alternatives for energy and chemicals is of primary importance. Among many proposed
solutions, biomass is seen as one of the alternatives that could help to supplement the
energy market and most importantly provide renewable platform chemicals and mate-
rials to support economies in the future.
3.3 Biomass
3.3.1 Renewable Energy and Renewable Carbon
In the simplest terms, biomass could be defined as a biological material derived from
living or recently living organisms. These organisms are mainly plants and other pho-
tosynthetic organisms. In principle, all the organisms that utilise chemical energy from
plant biomass indirectly by indigestion or decomposition of plant matter through the
food web can be considered as biomass. Throughout this chapter, however, we focus
predominantly on plants as the most important contributors to biomass production on
earth, and unless stated otherwise biomass will be synonymous with plant matter.
Plants are photosynthetic organisms that produce their cellular structures through
photosynthesis, an unique process that converts the energy of the sun and two simple
inorganic molecules – water and carbon dioxide – into chemical energy stored in plant
biomass (Figure 3.3). Biomass is therefore a form of solar energy that has been captured
and stored in the form of large chemical molecules like carbohydrates, lipids, aromatic
compounds, proteins and others. Once collected, this chemical energy can be stored for
prolonged periods of time and released on demand to yield other forms of usable energy
like heat, work or other useful chemical compounds. There are many compounds that
can be produced from biomass, for example, fuels – transportable form of chemical
energy, but also platform chemicals, biopolymers and other compounds of high utility
totheeconomies.Thisplacesbiomassconversiontechnologiesattheforefrontofmost
important technologies needed for the transition from fossil-based economy to the
low-carbon economy of the future. For the realisation of low-carbon economy, two
aspects are absolutely essential: renewable energy and renewable carbon (renewable
materials). Whereas there exist numerous alternatives to produce renewable energy
such as hydro, wind, solar, geothermal, wave and tidal technologies, there are only
limited array of options to replace fossil-derived platform chemicals such as olefins
(ethylene or propylene), aromatics (benzene, toluene, xylene) or butadiene. These
platform chemicals are currently processed into an array of consumer products that
