Rentech, Inc. has proposed a new renewable energy facility, Rialto Renewable Energy Center, at Rialto, California. This facility is scheduled to produce both synthetic fuel and bioelectricity primarily from waste biomass feedstock. Rentech is currently negotiating with local haulers in regards to sourcing primary feedstock in the form of urban waste biomass, such as yard clippings. According to Rentech, the aim is for the plant called to have a near zero carbon footprint.
The facility’s expected output is 600 barrels a day of synthetic fuel and 35 megawatts of renewable electricity, enough to power a staggering 30,000 homes. Rentech has agreements with a handful of organizations such as SilvaGas Corporation for its gasification technology and UOP for the conversion of the synthetic gas into fuel. Besides urban waste, the Rentech facility will also use bio-solids supplied by EnerTech Environmental as part of its total feedstock.
Renewable energy in US
Energy usage in the United States is presently dominated by hydrocarbon sources and will continue to be for decades. In the case of petroleum, US is highly dependent on imported sources. In the case of coal, US has rich domestic sources, but its use for the generation of electricity presents many challenges for minimizing its contribution to air pollution. The desire to reduce both pollution and foreign energy dependence has driven efforts at development of renewable energy sources. Their benefits are well known: in most cases, they produce little or no pollution emissions and because the resources are renewable, they reduce dependance on foreign supplies and more importantly on finite resources of any kind.
Renewable energy trends and current use in US
Renewables currently provide 9 percent of U.S. electricity supply, although this varies greatly by region.
Growth in the renewable energy industry is even more difficult to forecast than for more conventional energy sectors, as it is still a relatively small sector in US; it is largely dependent upon conventional fuel prices, and is increasingly being driven by government mandates.
Figure 1 shows trends in renewable energy consumed by source in the United States, 1949 to 2004, and illustrates that:
• Renewable energy has traditionally been dominated by hydroelectricity and wood, although over the past two decades other renewable sources have begun to appear.
• Through 2030, hydro and wood will continue to dominate, although the other renewable sources will gradually increase in importance.
Figure 1 U.S. renewable energy consumption, by source, 1949-2005.
NOTE: Data for renewables other than hydro and wood N.A. prior to 1980s.
SOURCE: EIA, 2006a.
Figure 2 shows another representation of the sources of renewable energy in the United States in 2005, and illustrates that:
• Hydro accounts for 45 percent of renewable energy, and wood accounts for 31 percent.
• Much smaller shares consist of biomass, alcohol fuels, solar, and wind.
Figure 2 Relative shares of renewable energy consumption in the United States, 2005.
SOURCE: EIA, 2006a.
Figure 3 shows trends in renewable energy consumed in the United States by sector, 1949-2005, and illustrates that:
• Most renewable energy is consumed in the industrial sector, followed by consumption in the residential sector.
• Consumption in the transportation sector (alcohol fuels) was negligible for most of this period, but has increased its share recently.
Figure 3 U.S. renewable energy consumption, by sector, 1949-2005.
NOTE: Data on renewable fuel (ethanol) used in transportation not available prior to 1981.
SOURCE: EIA, 2006a.
A closer look at statistics from 2005 indicates that:
• Approximately 60 percent of renewable energy was used in the industrial sector and 21 percent was used in the residential sector.
• Fourteen percent was used in the transportation sector, and 5 percent was used in the commercial sector (EIA, 2006a).
Figure 4 shows the power capacity of various forms of renewables.
SOURCE: Renewable Energy Policy Network for the 21st Century, Renewables 2007 Global Status Report (www.ren21.net)
The above discussion reveals that though the importance or renewable is being realized, yet it is not being utilized optimally. I hope US comes up with more plans like Rialto Renewable Energy Center to reduce their dependence on fossil fuels.