Carbon-neutral fuel

Centi G, Perathoner S, Passalacqua R, Ampelli C. Solar production of fuels from water and C02. In Muradov NZ, Veziroglu TN, editors. Carbon-neutral fuels and energy carriers. Boca Raton, FL CRC Press (Taylor Francis Group) 2012. p. 291-323. 

In 2002, a prominent collection of scientists wrote, Biomass plantations can produce carbon-neutral fuels for power plants or transportation, but photosynthesis has too low a power density ( 6 W/m2) for biofuels to contribute significantly to climate stabilization. These researchers find the scale of our growing energy demand so daunting that they conclude that none of today s current options for renewable energy or energy efficiency are up to the... 

Synthetic hydrocarbon fuels from Hgnocellulosic biomass, in Carbon-Neutral Fuels and Energy Carriers (eds N. Muradov and N. Veziroglu), Taylor Francis, CRC Press, New York, to appear. 

Olah, G. A., Goeppert, A., Suiya Prakash, G. K. (2009). Chemical recycling of carbon dioxide to methanol and dimethyl ether from greenhouse gas to renewable, environmentally carbon neutral fuels and synthetic hydrocarbons. Journal of Organic Chemistry, 74, 487—498. http //dx.doi.org/10.1021/jo801260f. 

Even though the alcohols are less energy efficient than hydrocarbon fuels, they still have the advantage that they can be produced from renewable sources. Ethanol can be produced by fermentation, which initially suggested that ethanol was a carbon-neutral fuel. 

Domestic biomass heating can today be found in the increasing popularity of wood stoves. A wide variety of wood-burning appliances are used by households, particularly in rural areas of countries with traditional forest cultures such as Canada, Austria, Finland and Sweden. Since wood fuel was classified as a carbon-neutral fuel under the Kyoto Protocol, most countries that require winter space heating have begun to look again at wood. 

Olah, G. A. Goeppert, A. Surya Prakash, G. K. Chemical Recycling of Carbon Dioxide to Methanol and Dimethyl Ether From Greenhouse Gas to Renewable, Environmentally Carbon Neutral Fuels and Synthetic Hydrocarbons. J. Org. Chem. 2009,74, 487 98. 

CO2 represents an attractive and potentially useful process [90]. Ideally, the conversion should be carried out with electrical energy from a renewable generation system such that carbon-neutral fuels are obtained [134],... 

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)... 

In the case of biomass-derived fuels, the C02 emitted by carbon-containing fuels is absorbed from the atmosphere during the growth of the plants. As a result, the combustion of biomass-derived fuels is assumed to be C02 neutral at a global scale. 

To meet the demand for 10-20 TW of carbon neutral energy, three options are viable (a) fossil fuel use in conjunction with carbon sequestration (b) nuclear power (c) renewable sources. 

Hydrogen can be produced from carbon-free or carbon-neutral energy sources or from fossil fuels with CO capture and storage (sequestration). Thus, the use of hydrogen could eventually eliminate greenhouse gas emissions from the energy sector. 

The concept of this process is shown in Figure 6. The carbon in biomass which is fixed by photosynthesis from atmospheric C02 is converted into i) solid carbon (various kinds of charcoal, carbon and graphite) for use as materials or for storage, which is a stable state of carbon element ii) synthetic fuels such as FT diesel oil, DME or hydrogen, which can replace fossil fuels as carbon neutral alternate fuels (Hori, 2007, 2007a, 2007b). 

Biodiesel to Fuel a Large Power Plant. Researchers at ASU s Center for Bioenergy and Photosynthesis have calculated that a 25 x 25 km field of bioreactors using cyanobacteria to fix carbon could uptake all of the carbon dioxide produced by a 1.6 GW power plant and subsequently provide the biomass as lipid to fuel the power plant. The parameters necessary to achieve this goal are a seven percent power conversion efficiency for photosynthesis, 40 percent conversion efficiency of biomass to fuel, 50 percent conversion efficiency of fuel to electricity, and 80 percent conversion efficiency of land area covered by the bioreactors. This system would then be carbon neutral in operation and produce about 1.6 GW of electrical power. The key to making this feasible is to achieve a seven percent power conversion efficiency for cyanobacteria. Moore noted that the area required to produce a specified amount of energy scales directly with the energy conversion efficiency of the system or device. 

Biomass resources will become more important in the future as alternative chemicals and fuel from fossil resources. Such alternatives can be carbon-neutral and renewable. Therefore, the use of biomass is of benefit for our global environments. The present study has clearly demonstrated a potential of woody biomass resources to be converted into useful chemicals in supercritical water. In addition, the products derived from cellulose and hemicelluloses were effectively separated from lignin-derived products. This raises the possibility of converting whole biomass substrates to alternative chemicals, and provides ample opportunities for human beings to produce useful biomass-based products as chemicals and bio-fuels W ithout using fossil resources... 

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