Archive for January, 2010

Nasa Confirms Liquid Lake on Saturn Moon

NASA scientists have concluded that at least one of the large lakes observed on Saturn’s moon Titan contains liquid hydrocarbons, and have positively identified the presence of ethane. This makes Titan the only body in our solar system beyond Earth known to have liquid on its surface. Scientists made the discovery using data from an instrument aboard the Cassini spacecraft. The instrument identified chemically different materials based on the way they absorb and reflect infrared light. Before Cassini, scientists thought Titan would have global oceans of methane, ethane and other light hydrocarbons. More than 40 close flybys of Titan by Cassini show no such global oceans exist, but hundreds of dark, lake-like features are present. Until now, it was not known whether these features were liquid or simply dark, solid material. “This is the first observation that really pins down that Titan has a surface lake filled with liquid,” said Bob Brown of the University of Arizona, Tucson. Brown is the team leader of Cassini’s visual and mapping instrument. The results will be published in the July 31 issue of the journal Nature. Ethane and several other simple hydrocarbons have been identified in Titan’s atmosphere, which consists of 95 percent nitrogen, with methane making up the other five percent. Ethane and other hydrocarbons are products from atmospheric chemistry caused by the breakdown of methane by sunlight. Some of the hydrocarbons react further and form fine aerosol particles. All of these things in Titan’s atmosphere make detecting and identifying materials on the surface difficult, because these particles form a ubiquitous hydrocarbon haze that hinders the view. Liquid ethane was identified using a technique that removed the interference from the atmospheric hydrocarbons. The visual and mapping instrument observed a lake, Ontario Lacus, in Titan’s south polar region during a close Cassini flyby in December 2007. The lake is roughly 20,000 square kilometers (7,800 square miles) in area, slightly larger than North America’s Lake Ontario. “Detection of liquid ethane confirms a long-held idea that lakes and seas filled with methane and ethane exist on Titan,” said Larry Soderblom, a Cassini interdisciplinary scientist with the U. S. Geological Survey in Flagstaff, Ariz. “The fact we could detect the ethane spectral signatures of the lake even when it was so dimly illuminated, and at a slanted viewing path through Titan’s atmosphere, raises expectations for exciting future lake discoveries by our instrument. “The ethane is in a liquid solution with methane, other hydrocarbons and nitrogen. At Titan’s surface temperatures, approximately 300 degrees Fahrenheit below zero, these substances can exist as both liquid and gas. Titan shows overwhelming evidence of evaporation, rain, and fluid-carved channels draining into what, in this case, is a liquid hydrocarbon lake. Earth has a hydrological cycle based on water and Titan has a cycle based on methane. Scientists ruled out the presence of water ice, ammonia, ammonia hydrate and carbon dioxide in Ontario Lacus. The observations also suggest the lake is evaporating. It is ringed by a dark beach, where the black lake merges with the bright shoreline. Cassini also observed a shelf and beach being exposed as the lake evaporates. “During the next few years, the vast array of lakes and seas on Titan’s north pole mapped with Cassini’s radar instrument will emerge from polar darkness into sunlight, giving the infrared instrument rich opportunities to watch for seasonal changes of Titan’s lakes,” Soderblom said. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Science Mission Directorate, Washington. The Cassini orbiter was designed, developed and assembled at JPL. The Visual and Infrared Mapping Spectrometer team is based at the University of Arizona.

Solar Energy Profile: Straight from the Source

Every day, the Earth receives more energy from the sun than mankind uses in a year. Still, solar energy remains a tiny sliver in the global energy mix. Falling prices and better efficiency could change this, but can it happen fast enough?When it comes to meeting energy needs, humanity has not been able to eliminate the middle man. The energy we use today comes from the sun, but we get it indirectly. Sunrays fed countless generations of plants and organisms millions of years ago, which we now use to burn to produce electricity, heat our homes, and run our cars. Its heat also strikes up the winds that we use to sail ships and run turbines. Despite our dependence on the sun, mankind has still not fully realized the potential of harnessing the sun?s vast energy directly. Worldwide Importance and Future TrendsEven with steady annual growth, the International Energy Agency says solar energy – combined with wind and geothermal power – still only supplies less than one percent of the world?s energy. In Germany, the global solar market leader, solar supplies around 0. 3 percent of national electricity demand; in the United States, it supplies less than 0. 1 percent. The UN?s annual “Global Trends in Sustainable Development” report said that the solar sector attracted 16 percent of the 70 billion U. S. dollars invested in renewable technology in 2006 – behind wind (38 percent) and biofuels (26 percent). According to the World Energy Council, solar water heating market is growing at a rate of around 20 percent a year, and solar PV at 35 percent. If the costs of solar technology continue to drop, it has a chance to compete with other forms of energy production. In places like sunny California, solar has already reached “grid parity,” which means the costs of producing solar power are now competitive with conventional energy production even without government subsidies. Sinking production costs would allow solar power to eventually join or even replace coal, gas, and oil as a primary energy source by the end of the century, which some experts say is possible. Global Resources and ProducersThe amount of solar energy that reaches the Earth?s surface every 20 days exceeds the energy trapped up in all of the planet?s coal, oil, and natural gas reserves. The trick is finding cost-effective and efficient ways of converting this abundant resource into usable energy. Currently, there are two main ways of doing so. Photovoltaic (PV) panels, thin pieces of crystalline silicon, transfer sunlight directly into electricity. Solar thermal collectors, on the other hand, are used to heat water for domestic or industrial use and to run steam power plants. Germany is the world?s leading producer of PV and solar heating technology and energy. In 2006 alone, 968 Megawatts (MW) of PV was installed in Germany. Japan, which added 292 MW last year, is also an important market and exporter of PV technology. China is aggressively adding solar systems to its energy mix. The country already consumes half of all solar-heated water in the world, and aims to increase solar water heater coverage by 50 percent by 2010. China is also emerging as an important producer and consumer of PV cells, which the government is integrating in remote and urban area. Energy OutputThe energy output of photovoltaic and solar heating depends on the size location of the system. Most areas receive ample sunlight, but deserts that seldom get cloud cover are better suited for solar energy production. Standard PV cells have an energy conversion rate of 6 to 8 percent, meaning that 6 to 8 percent of all solar power absorbed is turned into energy. Some prototypes have already achieved conversion rates of more than 40 percent, but are still too expensive for mass-market production. Solar heaters utilize solar collectors that are significantly more efficient. Current collectors turn between 60 to 70 percent of absorbed sunlight into heat. Concentrated solar thermal systems use mirrors to reflect sunlight onto a tower, producing extremely hot temperatures to boil water or other fluids and produce steam to drive a thermal power plant. An 11 MW concentrating solar power plant was completed near Seville, Spain in March 2007. A 154 MW facility is planned in Australia, and a 500 MW system in California?s Mojave Desert. Environmental Impact and DrawbacksManufacturing and installing solar systems requires energy, and as with almost any industrial activity, involves handling hazardous materials, such as arsenic and cadmium. Mass production of PV cells is sometimes marred by shortages of quality silicon. Large-scale solar power plants also take up lots of land. Overall, however, the environmental impacts of switching to solar energy are positive. Solar heaters require significantly less fossil energy input than natural gas and electric systems. PV systems are cleaner energy producers compared to coal and oil. Greenhouse gas emissions of solar PV plant including production and installation are eight times less than that of a coal-fired plant. The initial costs of solar heating and PV systems, however, prevent many homeowners from installing them. But falling costs and subsidies have helped sustain market growth in some countries. Like with wind turbines, another technical problem is effectively storing solar energy to provide power throughout nights and cloudy days.

Germany’S Bid For Solar Excellence Scuppered By Geothermal?

In 1991, a quiet but effective revolution began in Germany. It consisted of 5 paragraphs and didn’t even provide any future promises (or funding), but it gave something to the average citizen that he didn’t have before. . . commercial access to the grid. The law was entitled Stromeinspeisungsgesetz (commonly known in the U. S. as the Energy Feed-in Law). From 1991, all suppliers of electricity, including private citizens, were granted access to the electrical grid and, by law, would be compensated at an unprecedented premium for all energy sent into the network. By far, the highest commissions were paid to the suppliers of solar power, starting a race to go solar in Deutschland. ? The law was revised in 2000 and now called the Renewable Energy Sources Act to include energy supplied by geothermal derivations such as geysers, natural steam, geopressurized reservoirs, etc. Perhaps not something the average person has access to, but certainly of interest on a corporate level. Ironically, most geothermal energy is not very “renewable” as it is mined faster that it can regenerate, but it is clean and efficient. There is no mistaking that this addition was added, in fact, to attract new business to the clean energy market. More importantly, the 2000 version set a time frame for new investors to 20 years. What that achieved was the insurance and reassurance that people needed before such a huge commitment to their individual projects. On the negative side, the 20 years came with decreased tariffs over time. Why decrease the tariffs? Simply put, the government had set a ceiling of 5% total energy production by the methods outlined in the original Stromeinspeisungsgesetz. Solar panels were going up all over Germany faster that you can say “sauerbraten”. Although not funded directly by the government, budget considerations still had to be weighed as the electricity consumer picked up the tab for the subsidies. The tariff reductions simply mitigated the government’s set budget for the project. In addition, the newer law put Germany in line with the EU’s energy regulations requiring frequent review, rates reflective of overall cost, different rates based on type, different rates based on size of facility, and a generally degressively mobile payment structure. The goal of this bill was to reduce carbon emissions by 3% by 2010 and enable green electricity to become 10% of the overall energy supply by the same year. This goal was surpassed in 2007, at which point 12. 5% of total energy was green energy. ? In keeping with the EU’s standard of “frequent performance review,” the law was once again revised in 2004. This time, no great name change. It became the 2004 Renewable Energy Sources Act. Since reaching goals set in 2000 so early, this revision raises to bar to 27% by 2020. These enterprising ambitions and the tools implemented to achieve these agendas have put Germany forward as a renewable energy pioneer in terms of sheer scale. The newer law accounted for up and coming market developments and rewards for innovation in sustainable sources of power. Since the initiation of the Renewable Energy Sources Act, tariffs paid out to suppliers have been more finely tuned, promoting photovoltaic, geothermal, and biomass overall. However, payouts under this bill were dynamic with new developments and technologies. Wind power payments under the 2004 act, for example, were reduced due to a reduction in overall costs secondary to technological advances. By degressing fees paid to suppliers, the government hopes to ignite creative stream-lining innovations, which, based on fluctuating payments, rewards the design model, but saves on the long term. Another aspect of the 2004 legislation is the fixed tariff scheme. Suppliers could “lock in” a rate based on the year of initiation. The rate would be good for 20 years plus the year of commencement. Once again, this is a call to action. The sooner you’re in, the more profit you can extract. Producers of electricity are protected from future changes to the law by this key piece of the legislation. ? As of 2008, amendments in the Energy Act, or EEG (Erneubare Energien Gesetz) lessen the focus on solar production by reducing the tariff for rooftop solar panels by 8% in 2009 and 2010 and then 9% annually after that. Ground level solar parks will suffer a 10% reduction in compensation in 2009 and 2010 (a decrease of 3. 5%). Wind energy promotion is the focus of the latest revisions set forth by the governing body. So, is wind the new King of Renewables? Solar power is perhaps less heavily promoted than in the past, but one must see that as a sign of success of the program. Falling subsidies indicate that the industry is healthy and has less need for gross promotion. Is wind the next “big thing” in Germany? Don’t count out geothermals just yet. Although the “renewability” of geothermal power is in debate, geothermal drilling goes on and was given an early boost in 2000 and further support in 2004. There are currently 150 geothermal plants in the development stage held back at the moment due to the cost of the drilling equipment necessary. Not to be daunted, German manufacturing plants are expanding drill production for the sector. Six geothermal plants are in the process of opening this year (2009) and into 2010. So, what does this mean for the rest of us? Well, look at it this way. A country with relatively moderate sun exposure and no volcanic activity in 7,500 years is actually a leader in producing solar power and geothermal energy. To say that Germany is inspiring is a vast understatement. If the U. S. made a serious attempt to duplicate Germany’s success, the impact on the environment would be staggering. U. S. representative Jay Inslee from Washington state introduced the Renewable Energy Jobs and Security Act in June of 2008, but it stalled. On a brighter note, Gainesville, FL just passed a law (March 2009) to compensate providers of solar electricity at a premium rate through net metering. City officials passed this bill unanimously after studying the success in Germany. Hawaii isn’t far behind and will likely have a similar plan in effect by the end of the year. I think that this is how we are going to achieve results in the U. S. : one state at a time until the job is done. 15-Mar-09 ?

Sources of Alternative Energy – Including Resources, Forms, Stocks and Investment

The Ocean, Nuclear and Solar Power are forms of alternative energy which can be developed.

Ocean Thermal Energy Conversion (OTEC) is a potential alternative energy source that needs to be funded and explored much more than it presently is.

There are three kinds; closed, open and hybrid cycle of OTEC.

?Closed Cycle? uses a low-boiling point liquid such as, for example, propane to act as an intermediate fluid. The OTEC plant pumps the warm sea water into the reaction chamber and boils the intermediate fluid. This results in the intermediate fluid’s vapor pushing the turbine of the engine, which thus generates electricity. The vapor is then cooled down by putting in cold sea water.

?Open Cycle?. The sea water itself is the driver of the turbine engine in this OTEC format. Warm sea water found on the surface of the ocean is turned into a low-pressure vapor under the constraint of a vacuum. The low-pressure vapor is released in a focused area and it has the power to drive the turbine. To cool down the vapor and create desalinated water for human consumption, the deeper ocean’s cold waters are added to the vapor after it has generated sufficient electricity.

?Hybrid Cycle? There are actually two sub-theories to the theory of Hybrid Cycling. The first involves using a closed cycling to generate electricity. This electricity is in turn used to create the vacuum environment needed for open cycling. The second component is the integration of two open cyclings such that twice the amount of desalinated, potable water is created that with just one open cycle.

Developing Nuclear Power as Alternative Energy

Nuclear power plants are very ?clean-burning? and their efficiency is rather staggering. Nuclear power is generated at 80% efficiency, meaning that the energy produced by the fission reactions is almost equal to the energy put into producing the fission reactions in the first place. There is not a lot of waste material generated by nuclear fission?although, due to the fact that there is no such thing as creating energy without also creating some measure of waste, there is some. The concerns of people such as environmentalists with regards to using nuclear power as an alternative energy source center around this waste, which is radioactive gases which have to be contained.

Solar Energy Collecting as an Alternative Energy Source

Solar powered electricity generation is certainly good for the environment, as this alternative form of producing energy gives off absolutely zero emissions into the atmosphere and is merely utilizing one of the most naturally occurring of all things as its driver. Solar collection cells are becoming slowly but surely ever more practical for placing upon the rooftops of people’s homes, and they are not a difficult system to use for heating one’s home, creating hot water, or producing electricity. In the case of using the photovoltaic cells for hot water generation, the system works by having the water encased in the cells, where it is heated and then sent through your pipes.

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