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The new renewables
1st October, 2008
Fonte: http://www.biofuels-news.com/articles/v10_a6.html. Adaptado. The term biofuel refers to more than just biodiesel and bioethanol. Although other renewables, such as biomethanol, biomethane and DME, may still only be in the early stages of development, several small scale projects are beginning to show large potential.

Oil is still the fuel of choice for 98% of motorised transportation today, the International Energy Agency (IEA) states in a report released in 2008. That means that less than 2% of total transport liquid fuel supply is derived from biofuels, although several government initiatives are attempting to change this figure.

However, just using biofuels is no longer enough. These renewable fuels must come from sustainable, ideally second generation sources. This technology will not be viable for the better half of a decade, so in the meantime other alternatives are in development.

From rubbish to renewable energy
The US government is considering what to do with the waste piling up on national landfill sites. One solution is to collect the methane gas and use it as a renewable energy source for the production of biofuel. Landfill gas is the natural by-product of aerobic decomposition of municipal solid waste (MSW).

Landfill gas is used in biofuels production in two ways. It can provide fuel to power conventional ethanol or biodiesel production, or it can function as a raw material in a number of biodiesel applications. These include: compressed natural gas to fuel buses and fleet vehicles, liquefied natural gas (LNG) in rubbish trucks, the manufacture of synthetic diesel, creation of methanol, and production of biodiesel.

Fonte: http://www.biofuels-news.com/articles/v10_a6.html. Adaptado.

No trecho do primeiro parágrafo -- Although other renewables, such as biomethanol, biomethane and DME, may still only be in the early stages of development, -- a expressão such as indica