Lignocellulosic biomassLignocellulose refers to plant dry matter (biomass), so called lignocellulosic biomass. It is the most abundantly available raw material on the Earth for the production of biofuels. It is composed of two kinds of carbohydrate polymers, cellulose and hemicellulose, and an aromatic-rich polymer called lignin. Any biomass rich in cellulose, hemicelluloses, and lignin are commonly referred to as lignocellulosic biomass. Each component has a distinct chemical behavior.
Fossil fuel subsidiesFossil fuel subsidies are energy subsidies on fossil fuels. They may be tax breaks on consumption, such as a lower sales tax on natural gas for residential heating; or subsidies on production, such as tax breaks on exploration for oil. Or they may be free or cheap negative externalities; such as air pollution or climate change due to burning gasoline, diesel and jet fuel. Some fossil fuel subsidies are via electricity generation, such as subsidies for coal-fired power stations.
TorrefactionTorrefaction of biomass, e.g., wood or grain, is a mild form of pyrolysis at temperatures typically between 200 and 320 °C. Torrefaction changes biomass properties to provide a better fuel quality for combustion and gasification applications. Torrefaction produces a relatively dry product, which reduces or eliminates its potential for organic decomposition. Torrefaction combined with densification creates an energy-dense fuel carrier of 20 to 21 GJ/ton lower heating value (LHV).
Geothermal activityGeothermal activity is a group of natural heat transfer processes, occurring on Earth's surface, caused by the presence of excess heat in the subsurface of the affected area. Geothermal activity can manifest itself in a variety of different phenomena, including, among others, elevated surface temperatures, various forms of hydrothermal activity, and the presence of fumaroles that emit hot volcanic gases. Earth's internal heat budget Geothermal activity mostly appears in volcanic provinces, in some cases it can be caused by underground fires or by large deposits of radioactive elements.
Shared Socioeconomic PathwaysShared Socioeconomic Pathways (SSPs) are scenarios of projected socioeconomic global changes up to 2100. They are used to derive greenhouse gas emissions scenarios with different climate policies. The scenarios are: SSP1: Sustainability (Taking the Green Road) SSP2: Middle of the Road SSP3: Regional Rivalry (A Rocky Road) SSP4: Inequality (A Road divided) SSP5: Fossil-fueled Development (Taking the Highway) They have been used to help produce the IPCC Sixth Assessment Report on climate change, published on 9 August 2021.