Group items tagged

IN WONKISH circles, energy efficiency used to be known as “the fifth fuel”: it can help to satisfy growing demand for energy just as surely as coal, gas, oil or uranium can. But in these environmentally conscious times it has been climbing the rankings. Whereas the burning of fossil fuels releases greenhouse gases, which contribute to global warming, and nuclear plants generate life-threatening waste, the only by-product of energy efficiency is wealth, in the form of lower fuel bills and less spending on power stations, pipelines and so forth. No wonder that wonks now tend to prefer “negawatts” to megawatts as the best method of slaking the world's growing thirst for energy.

Biofuels, once seen as a useful way of combating climate change, could actually increase greenhouse gas emissions, say two major new studies. And it may take tens or hundreds of years to pay back the "carbon debt" accrued by growing biofuels in the first place, say researchers. The calculations join a growing list of studies questioning whether switching to biofuels really will help combat climate change.

True or false: taking the commuter train across Boston results in lower greenhouse gas emissions than travelling the same distance in a jumbo jet. Perhaps surprisingly, the answer is false. A new study compares the "full life-cycle" emissions generated by 11 different modes of transportation in the US. Unlike previous studies on transport emissions, Mikhail Chester and Arpad Horvath of the University of California, Berkeley, looked beyond what is emitted by different types of car, train, bus or plane while their engines are running and includes emissions from building and maintaining the vehicles and their infrastructure, as well as generating the fuel to run them.

Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 2004–2006, this study presents the life-cycle greenhouse gas emissions, criteria pollutant emissions, and heavy metal emissions from four types of major commercial PV systems: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride. Life-cycle emissions were determined by employing average electricity mixtures in Europe and the United States during the materials and module production for each PV system. Among the current vintage of PV technologies, thin-film cadmium telluride (CdTe) PV emits the least amount of harmful air emissions as it requires the least amount of energy during the module production. However, the differences in the emissions between different PV technologies are very small in comparison to the emissions from conventional energy technologies that PV could displace. As a part of prospective analysis, the effect of PV breeder was investigated. Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.

The island of Barbados is 99% dependent on fossil fuel imports to satisfy its energy needs, which is unsustainable. This study proposes a 10 MW distributed wind energy scheme using micro wind turbines (WT) of horizontal (HAWT) and vertical axis (VAWT) configurations. These units are rated less than 500 W, and the scheme is hereafter referred to as mWT10. mWT10 is compared to the proposed 10 MW medium WT farm by the Barbados Light & Power Company (BL&P). The economic bottom line is the levelized cost of electricity (LCOE). The results highlight the BL&P proposal as the best economic option at BDS$0.19 per kWh, while that of both mWT10 configurations exceeds the conventional cost of BDS$0.25 by two to nine times. This is attributed to significantly higher relative installation and operational costs. However, the financial gap between mWT10 LCOE and the retail price of electricity is much smaller due to a large fuel surcharge passed on to each customer. Annual additional benefits of using wind energy include: greenhouse gas emissions savings of 6–23 kt of carbon dioxide; and anavoided fuel costs of BDS$1.5–5.3 million.

COAL-FIRED power stations should not be privatised but bulldozed over the next 20 years to curb greenhouse gas emissions, one of the state's leading energy academics has told the Iemma Government.

Renewable energy is an essential part of Australia’s low emissions energy mix and is important to Australia’s energy security. It plays a strong role in reducing Australia’s greenhouse gas emissions and helping Australia stay on track to meet its Kyoto target and beyond. Australian Government support for renewable energy assists industry development, reduces barriers to the national electricity market, and provides community access to renewable energy.

All newly built homes to produce more energy than they consume by 2020. Renovate all existing buildings to save energy. Ban incandescent light bulbs by 2010. Reduce greenhouse-gas emission by 20% by 2020. Increase renewable energy from 9% to 20-25% of total energy consumption by 2020. Bring transport emissions back to 1990 levels. Reduce vehicle speed limits by 10 kilometres per hour. Taxes and incentives to favour clean cars. Shift half of haulage by road to rail and water within 15 years. Develop rail and public transport. Reduce air pollutants quantitatively. Create a national network of "green" corridors and nature reserves. Increase organic farming from 2% to 6% of total acreage production by 2010 and to 20% by 2020. Ecological groups to be stakeholders, like trade unions, in government negotiations. Create a body to review planting of genetically modified crops on a case-by-case basis.

Agreement has been reached on the European Union Renewable Energy Directive that could paved the way for the economic bloc to achieve its plans for a 20% renewables contribution to total energy demand and a 20% cut in greenhouse gas emissions by 2020, the so-called 20:20:20 plan. The deal, between the European Parliament, the French Presidency, on behalf of the Council, and the European Commission, means that more than one third of EU electricity must come from renewables by 2020.

This question is generated by an advertising campaign by the railroad industry, which is arguing that a good way to reduce greenhouse gas emissions is to move more freight by rail rather than by truck. An example of the industry's ads can be seen on the Web site www.freightrailworks.org.

Distributed generation (DG) and renewable energy sources (RES) are attracting special attention. Both are seen as important in achieving two key goals:Increasing the security of energy supplies by reducing the dependency on imported fossil fuels such as oil, natural gas and coalReducing the emission of greenhouse gases, specifically carbon dioxide, from the burning of fossil fuels.