Fuels, renewable

The quality of gasoline is also improved by the addition of ethanol, which has an octane rating of 120. The use of ethanol helps to reduce the demand for petroleum. Unlike petroleum, ethanol is a renewable fuel that can be regenerated every year (see Box 6.2). 

EPA (2009b). EPA Lifecycle Analysis of Greenhouse Gas Emissions from Renewable Fuels. http //www.epa.gov/otaq/fuels/renewablefuels/index.htm (accessed 25.10.10). 

Table 3. GHG emissions per kilometer travelled using renewable fuels and fossil fuels [28]...

That is why, since 1969, the global C02 emissions from energy use grew at the fastest rate [1], Therefore, renewable fuels (including biofuels) have been grown fast which are expected to grow at 8.2% p.a. from 2010 to 2030 [2]. One of the new energy sources is fuel from waste. 

Develop methods to use biomass as a renewable fuel source. 

Bridgwater, A. V., Renewable fuels and chemicals by thermal processing of biomass. Chemical Engineering Journal 2003,19, 87-102. 

Biofuels Carbon neutral Higher biodiversity Local source of energy Mitigate climate change Renewable fuels Ceotto (2009) Lai (2009d, e) Hill (2009) Miah and Hussein (2009) Scholz et aL (2009)... 

If H2 is made from renewable fuels such as biomass, or nuclear energy, or fossil fuel resources with C02 capture and sequestration, it would be possible to generate emission-free electricity in the future. 

Fig. 4 Major ethanol producing countries in the world in 2004 (F. O. Licht, cited in Renewable Fuel Association, Homegrown for the Homeland Industry Outlook 2005, (Washington, D.C 2005), p. 14.

The nation s first E85 (85% ethanol) fueling station opened in La Habra, CA in 1990, operated by the California Renewable Fuels Council. 

The U.S. Environmental Protection Agency (EPA) has established the Renewable Fuel Standard (RFS). The RFS was mandated by the Energy Policy Act of 2005. It requires that by 2012, at least 7.5 billion gallons of renewable fuel be blended into motor vehicle fuel sold in the U.S. 

The program is based on a credit trading system that provides a flexible way to comply with the annual standard by allowing renewable fuels to be used where they are most economical. By 2012, the program may cut petroleum use by almost 4 billion gallons and reduce annual greenhouse gas emissions by 13 million metric tons. This would be the equivalent of removing about 2.4 million cars from the road. 

By 2007, about 4% of all the fuel sold or dispensed to U.S. motorists came from renewable sources, which is almost 5 billion gallons of renewable fuels. New and expanded plants now under construction are expected to push the annual production of ethanol well above this level. 

Shell has spent about 1 billion on renewable fuels since 2000. Shell has invested largely in next generation cellulosic biofuel which is a longterm commitment. 

Cogeneration systems can also use renewable fuel sources such as wood, waste products, wood gas or methane from sewage and garbage. The Sun-Diamond plant in Stockton, California used waste walnut shells into electricity for the plant and nearby homes. The walnut shells were used as fuel to produce steam to drive a turbine generator. The low-pressure steam output was then used for heat as well as to refrigerate the plant. The Sun-Diamond cogeneration system produced about 32 million KWH of electricity per year. It only used 12 million and sold the surplus power to Pacific Gas and Electric Company. 

Figure 7.2. Supply paths for renewable fuels (FVS, 2003 Specht et al., 2001).

Lower efficiencies as a future renewable fuel from sources other than (fairly limited) biomass. 

In 2005, a Renewable Fuel Standard (RFS) was enacted in the United States, which requires the annual volume of biofuels to be blended into gasoline to increase to 7.5 billion gallons (28 billion litres) by 2012. The mandatory Alternative Fuel Standard (AFS) from 2007 further requires 35 billion gallons (132 billion litres) of renewable and alternative fuels in 2017. 

Both in the USA and the EU, the introduction of renewable fuels standards is likely to increase considerably the consumption of bioethanol. Lignocelluloses from agricultural and forest industry residues and/or the carbohydrate fraction of municipal solid waste (MSW) will be the future source of biomass, but starch-rich sources such as corn grain (the major raw material for ethanol in USA) and sugar cane (in Brazil) are currently used. Although land devoted to fuel could reduce land available for food production, this is at present not a serious problem, but could become progressively more important with increasing use of bioethanol. For this reason, it is important to utilize other crops that could be cultivated in unused land (an important social factor to preserve rural populations) and, especially, start to use cellulose-based feedstocks and waste materials as raw material. 

There has been a recent revival in interest in the use of ethanol-diesel fuel blends (E-diesel) in heavy-duty vehicles as a means to reduce petroleum dependency, increase renewable fuels use, and reduce vehicle emissions [27]. E-diesel blends containing 10-15% ethanol could be prepared via the use of additives. However, several fuel properties that are essential to the proper operation of a diesel engine are affected by the addition of ethanol to diesel fuel - in particular, blend stability, viscosity and lubricity, energy content and cetane number (increasing concentrations of ethanol in diesel lower the cetane number proportionately) [28]. Materials compatibility and corrosiveness are also important factors that need to be considered. 

Efficient technology could also be developed based on catalytic biomass pyrolysis for the conversion of biomass into clean and renewable liquid bio-oil. This would facilitate its introduction into the energy market as a renewable fuel or as source of high value chemicals. It is possible to produce stable liquid biofuels from biomass flash pyrolysis, in a single stage catalytic process, although further developments are necessary. 

One of the biggest geopolitical problems associated with oil is that besides being a non-renewable fuel, is its unevenly distributed around the globe. 

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