Addressing global warming, however, is a highly complex and daunting endeavor. Many climate experts have urged the world to stabilize greenhouse gas concentrations in the atmosphere around 450 to 550 parts per million (ppm)—that is, no more than 450 to 550 units of greenhouse gases for every million units of air in the earth’s atmosphere. This approach, experts say, could keep average global temperatures at no more than 3.6° Fahrenheit (2° Celsius) above preindustrial levels, which could avoid some of the worst, irreversible consequences of climate change. (more…)

Nuclear energy has some distinct advantages in strengthening the external dimension of energy supply security. These include:

• Nuclear power plants produce electricity domestically. Their capital and labor inputs are also provided domestically. With more than 90% of its inputs in terms of value sourced domestically, it can be considered a largely domestic source of energy and electricity.

• Of course, a majority of OECD countries import part or all of their requirements of uranium plutonium. (more…)

Although the focus of many policy studies of climate change is on establishing the causal links between anthropogenic systems, emissions of greenhouse gases climate change, the line of causation also runs the other way. Short-term fluctuations in climate conditions, particularly in the temperate zones on the planet, affect energy consumption. If the popular expectation that the climate will become warmer becomes a reality, we can expect winters and summers that are warmer than those of the past. (more…)

The growth in air transportation volume has important global energy sustainable development
associated with the potential for greenhouse gases sources. On local to regional scales, noise, decreased air quality related primarily to ozone production and particulate levels, and other issues, such as roadway congestion related to airport services and local water quality, are all recognized as important impacts. (more…)

Fuel efficiency gains due to technological and operational change can mitigate the influence of growth on total emissions. Increased demand has historically outpaced these gains, resulting in an overall increase in emissions over the history of commercial aviation. The figure of merit relative to total energy use and emissions in aviation is the energy intensity (EI).

When discussing energy intensity, the most convenient unit of technology is the system represented by a complete aircraft. In this section, trends in energy use and energy intensity are elaborated. In the following section, the discussion focuses on the relation of energy intensity to the technological and operational characteristics of an aircraft.

Reviews of trends in technology and aircraft operations undertaken by Lee et al. and Babikian et al. indicate that continuation of historical precedents would result in a future decline in energy intensity for the large commercial aircraft fleet of 1.2–2.2%/year when averaged over the next 25 years, and perhaps an increase in energy intensity for regional aircraft, because regional jets use larger engines and replace turbo- props in the regional fleet. When compared with trends in traffic growth, expected improvements in aircraft technologies and operational measures alone are not likely to offset more than one-third of total emissions growth. Therefore, effects on the global atmosphere are expected to increase in the future in the absence of additional measures. Industry and government projections, which are based on more sophisticated technology and operations forecasting, are in general agreement with the historical trend.

Compared with the early 1990s, global aviation fuel consumption and subsequent CO2 emissions level could increase three-to sevenfold by 2050, equivalent to a 1.8–3.2% annual rate of change. In addition to the different demand growth projections entailed in such forecasts, variability in projected emissions also originates from different assumptions about aircraft technology, fleet mix, and operational evolution in air traffic management and scheduling.

We shows historical trends in energy intensity for the U.S. large commercial and regional fleets. Year-to-year variations in energy intensity for each aircraft type, due to different operating conditions, such as load factor, flight speed, altitude, and routing, controlled by different operators, can be 730%, as represented by the vertical extent of the data symbols. For large commercial aircraft, a combination of technological and operational improvements led to a reduction in energy intensity of the entire U.S. fleet of more than 60% between 1971 and 1998, averaging about 3.3%/year. In contrast, total RPK has grown by 330%, or 5.5%/year over the same period.

Long- range aircraft are B5% more fuel efficient than are short-range aircraft because they carry more passengers over a flight spent primarily at the cruise condition. Regional aircraft are 40–60% less fuel efficient than are their larger narrow- and wide-body counterparts, and regional jets are 10–60% less fuel efficient compared to turboprops. Importantly, fuel efficiency differences between large and regional aircraft can be explained mostly by differences in aircraft operations, not technology.

Reductions in energy intensity do not always directly imply lower environmental impact. For example, the prevalence of contrails is enhanced by greater engine efficiency. NOx emissions also become increasingly difficult to limit as engine temperatures and pressures are increased—a common method for improving engine efficiency. These conflicting influences make it difficult to translate the expected changes in overall system performance into air quality impacts. Historical trends suggest that feet-averaged NOx emissions per unit thrust during landing and takeoff (LTO) cycles have seen little improvement, and total NOx emissions have slightly increased. However, HC and CO emissions have been reduced drastically since the 1950s.

The question has long been not whether or not to reduce air pollution, but by how much and by what means. Since the extent of the reduced discomfort and illness is not clear—and the measurement of peoples’ willingness-to-pay (WTP) for reduced discomfort and illness is uncertain—it is not easy to know how much the pollution should be reduced. But it has always been clear that reducing automotive air pollution had to be part of the overall strategy. (more…)

The convention aims not only at stabilizing CO2 emissions in developed countries but also at ultimately reducing man-made CO2 emissions globally so as to stabilize the global climate. Environmental degradation cannot be singled out as an independent matter among various global issues. (more…)

Brazil produced about 18.5 million metric tones (20.4 tons) of processed sugar in the 2001/2002 harvest, with approximately 9.45 million metric tones (10.4 tons) used domestically and the rest exported. Brazilian sugar is mostly derived from sugarcane, a drought-tolerant tropical and subtropical crop containing about 12 to 17% sugars (90% sucrose, 10% glucose) and 68 to 72% moisture. Brazil grew about 272 million metric tones (300 million tons) of sugarcane in the 2001/2002 season, making it second to India in world cane production that year. In 1975, Brazil adopted a Pro-Alcool Program to convert sugar to ethanol to reduce dependence on petroleum imports that were damaging the economy. (more…)

The internal combustion engine has dominated the car and light-truck market for over 100 years. Although remarkable improvements have been made over the past 30 years to reduce air pollution problems to nearly zero and to almost double vehicle efficiency, increasing concerns about global warming and energy security are pushing vehicles toward even greater energy efficiency improvements. (more…)

In the beginning, human progress was limited by the amount of work in single day. This is only to feed themselves and their families. At that time, the economy was largely rural as a result. In the early of 19th century, more intelligent human began to looking for energy resources to support their lives. They began to develop coal, oil, and other stored energy to supplement their prime energy source: sunlight. Sunlight energy results in overgrown plant and animal growth over huge and dispersed areas and geologic time periods. There was, and will continue to be, abundant solar energy sources available to get more fossil fuel, to do research on how to exploit these resources more efficiently, and to use them in daily life and changing their cultures. (more…)