Environmental Engineering Reference
In-Depth Information
technologies, for ethanol to garner a significant share of the U.S. gasoline market,
ethanol producers need to deploy cost-competitive technologies for processing
agricultural residues and other biomass materials; it is unclear whether ethanol
from corn alone can achieve this result. Widespread deployment of ethanol also
faces infrastructure challenges—in particular, transporting and storing ethanol and
retrofitting gasoline station pumps. Barriers to electricity generation from
renewable sources—primarily wind and solar—include the difficulty of efficiently
converting renewable energy into electricity, high up-front capital costs, including
connection to the electric power transmission grid; the intermittent nature of wind
and solar energy; and the higher financial risks associated with gaps in the
renewal of the production tax credit. In addition, renewable energy technologies
must compete with traditional fossil energy sources whose greater environmental
costs are not reflected in the price paid by consumers, and renewable energy R
and D budgets have been subject to growing congressional earmarks in recent
years. For advanced fossil technologies, the primary challenge continues to be
controlling emissions of mercury and carbon dioxide generated by conventional
coal-fired plants. However, reducing these emissions requires plants to use new
coal gasification technologies, which cost about 20 percent more to construct than
conventional coal-fired plants and carry higher perceived investment risk as new
technologies. Furthermore, DOE and industry have not demonstrated the
technological feasibility of the long-term storage of carbon dioxide captured by a
large-scale, coal-based power plant. For advanced nuclear technologies, investors
face uncertainties about whether NRC's revised review process for new reactors
will effectively reduce regulatory delays and minimize added costs to address
safety concerns. While public opposition previously was a primary barrier, the
nuclear industry reports that public opinion, particularly in the southeast United
States, is more favorable reflecting the increased demand for electricity, perceived
advances in safety, and growing concerns about global warming. Investors also
face higher financial risk because of nuclear reactors' high capital costs and long
construction time frames, as well as environmental and nonproliferation concerns
about spent nuclear fuel.
While federal R and D has declined and the government has relied on the
market to determine whether to deploy advanced energy technologies, many states
have assumed higher profile roles by enacting standards, mandates, and financial
incentives primarily to stimulate renewable energy technologies that address their
growing energy needs and environmental concerns. In particular, 22 states have
established renewable portfolio standards requiring or encouraging that a fixed
percentage of the state's electricity be generated from renewable sources; 39
states have established rules for electric power companies to connect renewable
