Biofuel

A biofuel is as any fuel whose energy is obtained through a process of biological carbon fixation, this is a process that takes inorganic carbon (such as CO2) and converts it into a organic compound, as plants do with photosynthesis. Proteins, fats, and alcohols are all organic compounds, with molecules that can be used to provide energy, hence they are also fuels.

A biofuel is a hydrocarbon made from a living organism, which in turn used for power or energy, also referred to as drop in hydrocarbon biofuels or renewable / green biofuels. Where as fossil fuels take millions of years to form biofuels can be produced or manufactured in shorter periods of time via gasification, pyrolysis and hydrothermal liquefaction (HTL) but also through refinery in the case of for example vegetable oils. They are less carbon intensive that fossil fuels and can be renewed more quickly replenishing stocks, aswell as make use of waste materials such as cooking oil or wood waste.

Biofuels are renewable in a shorter time frame than fossil fuels, so are a more sustainable option, some argue that there are also environmental benefits in terms of biodiversity improvments through the growth of biofuels. However because biofuels do produce greenhouse gases when they are burnt they might not neccesssarily be considered as green or sustainable as wind or solar power which have zero emmissions in use (though can have significant embodied carbon emission associated with manufacture). The potential area of land-used is also a debated issue regarding large scale biofuel production particularly if it would be other wise used for food crops, unless biofuels are produced from the crops waste products.

Below is a list of the most common biofuels, with the final being biomass which is infact any organic material that can be burnt, of which there are many.

[edit] Ethanol

Ethanol is a Gasoline/Ethane replacement but half the energy per mass, so takes twice as much for the same energy. It burns cleaner than gasoline, producing less carbon monoxide but more ozone and particulates contributing to smog. Car engines can run on ethanol with modification.

[edit] Biodiesel

Biodiesel is a diesel replacement and has only slightly less energy. It burns cleaner than diesel, producing less particulate and fewer sulfur compounds but engines have to be specially designed as it is more corrosive to engines parts.

[edit] Methanol

Methanol is a methane replacement and has less than half the energy, it is liquid whereas methane is a compressed gas.

[edit] Biobutanol

Biobutanol can replace gasoline or butane, it has slightly less energy than gasoline, but can run in any car that uses gasoline without modification.

[edit] Biomass

Biomass as a term refers to any organic matter, dead or living, if it can be burnt then it can be referred to as a biofuel. Many agricultural waste products such as corn kernels, sugar cane stalks, peanut husks etc are forms of biomass as is wood or woody grasses and plants. There are many different ways of increasing the density of these materials to improve their performance as a fuel through for example steam and compression, aswell as thermochemical processes of pyrolisis which converts the materials into more carbon dense charcoal or biochar products suitable as fuels.

[edit] Biofuel generation

AR5 Climate Change 2014: Impacts, Adaptation, and Vulnerability, Glossary, published by the Intergovernmental Panel on Climate Change (IPCC) suggests that:

• First-generation manufactured biofuel is derived from grains, oilseeds, animal fats, and waste vegetable oils with mature conversion technologies.
• Second-generation biofuel uses non-traditional biochemical and thermochemical conversion processes and feedstock mostly derived from the lignocellulosic fractions of, for example, agricultural and forestry residues, municipal solid waste, etc.
• Third-generation biofuel would be derived from feedstocks such as algae and energy crops by advanced processes still under development.

[edit] Related articles on Designing Buildings

• Advanced bioenergy.
• Biochar.
• Biogas.
• Biomass CHP.
• Biomass.
• Biomethane.
• Combined heat and power (CHP).
• District energy.
• Definition of tree for planning purposes.
• Drop-in hydrocarbon fuels
• Energy.
• Environmental impact of biomaterials and biomass (FB 67).
• Forests.
• Feed in tariff.
• Fossil fuel.
• Methane pyrolysis.
• Renewable heat incentive.
• Solid biofuel.
• Solid biomass.
• Stove.
• The benefits of urban trees
• The effect of trees on rights of light.
• The Institution of Civil Engineers.
• The use of timber in construction.
• Timber.
• Tree root subsidence.
• Trees.
• Types of timber.
• Types of boiler.
• Types of fuel.
• Wood pellet mill basics.