Greenhouse gases types

A secondary benefit is that efficiency gains in fossil fuel generation also reduce all types of harmful emissions, even carbon dioxide—the greenhouse gas suspected by many as a major culprit of climate change. A 45 percent efficient plant releases approximately 40 percent less COn per megawatt-hours of electricity produced than a 25 percent efficient plant that it might be replacing. 

By using renewable carbon from biomass, an improvement in the CO2 balance can be achieved. However, significant effects beyond the impacts on greenhouse gas emissions are possible, e.g., soil modification, eutrophication, impact on biodiversity, land requirements and water consumption. These aspects depend on different factors like feedstock type, scale of production, cultivation and land-management practices, location and downstream processing routes. The environmental implications of agriculture are sometimes difficult to assess by the LCA methodology and require further research. 

At this moment, the NIST Chemistry WebBook and the Beilstein are the two most useful search tools for molecular structure and property relations. There are many more types of properties available in the research literature of interest only to a smaller set of readers these will not be listed in the general-purpose handbooks, but are to be found in specialized books and journals. Our ability to search for such properties in the research literature on the Internet is increasing rapidly, and students should practice doing such searches. Many of the required properties have not been tabulated in a searchable electronic database for example, flammability, toxicity, ozone hole potential, and greenhouse gas potential. Information on health, safety, and the environment that is publicly available on websites is listed in the references. 

There are many possible formats for auctions of EU ETS allowances which can be divided into two broad types. These are ascending-bid auctions, in which bidders have the opportunity to raise their bids during the auction, and sealed-bid auctions in which bidders submit only their final offers. The preferred choice of format depends on the circumstances. For example, ascending-bid auctions may be easier to understand for inexperienced bidders and have been recommended for auctions of UK greenhouse gas emissions reductions in 2002 (Klemperer, 2004, p. 135) and the New Entrants Reserve (NER) in phase I of the EU ETS in the UK (DTI, 2005).24 However, in the case of EU ETS allowances, as long as Member States do not unnecessarily restrict competition in auctions (e.g. by allowing only one sector to participate in any given auction), there are many potential bidders and sealed-bid auctions should perform well. 

The Kyoto protocol had identified the development of an alternative biofuel from biomass as one of several areas deserving of research support, since this type of renewable fuel could help reduce greenhouse gas emissions. The use of bioethanol as a viable motor fuel to replace or augment gasoline is an attractive component of an integrated strategy to reduce the release of detrimental hydrocarbons, carbon monoxide, nitrogen oxide, sulfur dioxide, and aromatics (2-3). 

In recent years the concept of a fuel cell propulsion system has gained in attention as a result of the need to reduce the fossil fuel consumption and greenhouse gas emissions. Since the fuel cells suitable for vehicle application (polymeric electrolyte membrane fuel cells) are fuelled by hydrogen, and deliver power as long as fuel and air are supplied, they potentially can provide the range capabilities of an internal combustion engine when used in a power system, but with clean and quiet operation. Therefore, the fundamental benefit of this type of propulsion consists in the possibility to adopt pollution-free electric drive-trains, without the drive range limitations typical of traditional electric vehicles. 

The most important greenhouse gas at present is not carbon dioxide but water vapour, simply because there is so much of it in the atmosphere (Box 6.1). Volcanoes emit large amounts of water vapour (c. 1 Ttyr-1 Skelton et al. 2003), but even so this flux is minor compared to evaporation from the oceans and evapotranspiration from plants (c.0.25% see Fig. 3.12). In a warmer world, such as during the Cretaceous, the atmosphere can hold more water vapour. However, the extent of the warming caused by extra atmospheric water vapour is difficult to predict because clouds also exhibit an albedo effect, and the balance between the greenhouse and albedo effects varies with cloud type and altitude (Lovelock Whitfield 1982). 

Directive due to boost EU renewable energy use to 20% by 2020. The latter also aims for a substitution of 10% of transport fuels by biofuels in 2020 as a mandatory target for the Member States. Furthermore, this directive also defines minimum sustainability standards, e.g. a 35% reduction of greenhouse gas emission and a focus on the type of land used for biomass cultivation. 

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