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dimanche 9 novembre 2008

Wind and gas

Wind turbines generate electricity very irregularly, because the wind itself is inconsistent. Therefore wind turbines always need backup power from fossil fuels to keep the electricity grid in balance. Gas turbines are the best way to do this. They are able to respond quickly and push power production when wind generators stop suddenly. They can be turned on and off almost instantly, whereas traditional coal-fired plants need to be maintained in a very inefficient standby mode if they are to respond to large fluctuations in power demand.

A proliferation of windmills, then, can become a windfall for gas sellers, as the cases of Spain and Germany, Europe’s leading producers of wind power, show.

By the end of 2007 Spain had 14,700 megawatts (MW) of installed wind capacity, according to Enagás, which manages the national gas network, producing 8.7% of the country’s total power supplies. Most of these wind generators are located in scarcely populated areas, while the power consumption is concentrated in big cities with their many air-conditioned buildings. The peak load of the Spanish power grid is thus in the hot summer months—but this is precisely the time of year when there usually isn’t much wind.

For this reason, more and more gas turbines are being installed near consumers in the suburbs of Spain’s cities. Only last year, Spanish power providers added 6,400 MW of gas-turbine power capacity, taking the total installed capacity of gas turbines to 21,000 MW. Natural gas has become the main source of electricity generation in Spain, and according to Enagás, 99.8% of the gas used in Spain is imported. Most of this comes via pipeline from Algeria, but the import of liquid natural gas (LNG) by ships will increase.

Germany has more than 20,000 wind turbines with a total capacity of 21,400 MW. Wind power’s share of total electricity generation has risen in line with that of natural gas since 1990. Germany’s gas consumption for power generation more than doubled between 1990 and 2007, and now represents 11.7% of the country’s total power generation. The country imported 83% of its natural gas supplies.

Source: WSJ, 11/09/08

Norway's tax on emissions

In 1991, Norway became one of the first countries in the world to impose a stiff tax on harmful greenhouse gas emissions. Since then, the country's emissions have risen by 15%.

By making it more expensive to pollute, carbon taxes should spur companies and individuals to clean up. Norway's sobering experience shows how difficult it is to cut emissions in the real world

Norway gave exemptions to some local industries, such as fishing, because it feared the tax would damage economic growth and hurt employment. On the other hand, it levied on the oil and gas industry a $65 tax per ton of carbon emitted. In contrast, the cost of a permit to emit the equivalent of one ton of carbon in Europe's current cap-and-trade system is $35.

After the tax was passed, domestic oil and gas giant StatoilHydro was forced to rethink nearly every aspect of its drilling cycle.

Around the time the tax was being debated, Statoil was developing a new gas field in the North Sea. At the Sleipner field, the natural gas Statoil extracts from under the sea bed contains 9% carbon dioxide. That's too high for Statoil's customers, whose power plants are designed to burn gas with only 2% carbon dioxide. Before Statoil can sell the gas, it has to separate and discard some of the carbon dioxide. Usually the excess carbon dioxide is spewed directly into the air.

Statoil spent two years and some $200 million on the project, which was launched in 1996. Since then, some 10 million tons of carbon dioxide have been buried, saving Statoil about $60 million on its carbon tax bill every year.

Other industries that were successful in negotiating exceptions for themselves have made little progress. Paper manufacturers were given a low tax rate of between $16 and $18.40 per ton -- less than a third what the oil sector pays. For the country's biggest paper company, Norske Skog, the carbon tax amounted to only about $200,000 a year, it didn't have a major influence on its investments or project decisions

The carbon tax's most glaring failure was in the transportation sector. The tax has also done little to quench Norwegians' thirst for automobiles. The number of registered cars has risen 27% in the past decade. Norwegians are used to paying high prices at the pump: a gallon of gasoline costs around $9 to $10, and about 6% of the price comes from the carbon tax. Yet since two-thirds of Norwegians live in the countryside, they pay up and keep driving.

Europe struggled with a similar dilemma as it set up its "cap-and-trade" system to reduce greenhouse gas emissions by utilities and heavy industry. Regulators cushioned industry in the early years of the system, giving them little incentive to improve. As a result, emissions have crept up 1% a year since 2005.

A few countries have cut emissions without injuring their economies. Sweden and Denmark, both of which introduced a carbon tax, have reduced their greenhouse gas emissions by 14% and 8% respectively since 1990 while maintaining growth. Their emission reductions can't be attributed to the tax alone, economists say. Additional moves to encourage energy efficiency and renewable energy, which are government-subsidized, played a part.

Norway's strong economic growth -- gross domestic product has swelled 70% since 1990 -- has far outstripped its 15% rise in greenhouse-gas emissions, according to the Norwegian government. Since the tax hasn't reduced emissions enough, the country voluntarily joined the bloc's cap-and-trade system earlier this year.

Source: WSJ, 30/09/08

Sanyo's air wash

On the sidelines of the Group of Eight summit, Sanyo Electric Co. displayed a washing machine, dubbed Aqua, that uses high-powered air, or ozone, to wash closes without a single drop of water. The process of ozonation, which disinfects bacteria on contact, can air-wash clothes removing about 80% of biodegradable stains without using any water, according to Sanyo.

The company says a full-cycle of air-wash uses about twice as much electricity as a regular wash but only one-fifth the energy of a comparable full cycle wash and dry in part because the air wash doesn’t need a drying system. The Aqua washer can also purify and recycle water that has been used for a bath use for a regular wash, reducing the amount of fresh water required to a half-bucket.

Source: WSJ, 08/07/08