Hydropower Energy Facts Pros and Cons

hydropower pros and cons
The World Commission on Dams (WCD) was formed in 1998 by a joint initiative of the World Conservation Union (IUCN) and the World Bank (WB) after a historic meeting of leading dam proponents and opponents in Switzerland, with proceedings reported by Dorcey and others. The WCD was asked to discover the truth about the hydropower energy facts, hydropower energy pros and cons, cost, effect, and benefit of large dams and it functioned independently for 2 years at a cost of $10 million. The money was well spent, and at the end of that period the WCD produced a comprehensive report and numerous support documents, and then dissolved itself. The report and support documents remain on the Internet available to all, and they have changed forever the debate about dams. (more…)

Monitor Energy Consumption (LCD and CRT Displays)

Monitor Energy Consumption
Green computing has forced even the largest companies to rethink and refocus to use energy more efficiently. We have low-power processors, motherboards, memory modules, hard drives and technology energy efficiency even higher. But still, there are many devices that need to be look at if they are efficient enough. You still need to look at each individual product like LCD and CRD monitor displays to decide whether their effectiveness in reducing your monthly electricity bills.

Most of the nation’s approximately 61 million monitors are associated with desktop PCs and workstations, whereas some 13 million displays rely on video input (as seen in airports). (more…)

Personal Computers (PC) and Workstations Energy Consumptions

pc energy consumption
After lighting, personal computers (PC) and monitors have the highest energy use in office environments. Studies have shown that the power management of computers and monitors can significantly reduce the energy consumption per capita, saving hundreds or thousands of dollars per year in electricity costs. The energy consumption of computers and monitors will be needed by the amount of energy to work and how they are used is determined.

The installed base of approximately 71 million personal computers and 2.5 million workstations in 2000 consumed 17.4 and 1.8 TWh, respectively. (more…)

Electromagnetic Suspension (EMS): Technology Alternatives For Suspension And Propulsion

Electromagnetic Suspension
Electromagnetic Suspension (EMS) system in which an array of magnets is attracted upwards to a steel rail. It is possible to design the magnets so that there is an upward force produced by magnetic attraction that cancels the downward gravitational force: the magnets are suspended in space! If steel beams were mounted on either side of a “guideway,” then a vehicle with magnets on both sides could move along the guideway and be supported and guided by the steel rails. (more…)

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Hybrid Energy Systems: Introduction And Definitions

Hybrid Energy Systems
The term hybrid energy system refers to those applications in which multiple energy unit conversion devices are used together to supply an energy requirement. These systems are often used in isolated applications and normally include at least one renewable energy source in the configuration. Hybrid energy systems are used an alternative to more conventional systems, which typically are based on a single fossil fuel source. Hybrid energy systems may also be used as part of distributed generation application in conventional electricity grid. (more…)

Solar Dryer: Agriculture and Food Drying Systems

Solar dryers are special structures that enhance the drying power of the sun and protect the agricultural product from dust, dirt, and insects. Table below shows a block diagram of an active solar drying system, consisting of solar air collectors, a drying unit or chamber, and an air handling unit. An active solar drying system can accommodate the use of a backup heat source when there in not enough solar heat available. (more…)

The Growing Scarcity of Fossil Fuels

From prehistory until the Industrial Revolution, most energy sources used by humans were localized (i.e., available within 5–10 miles of end users). Energy sources included draft animals, human slaves, and renewable sources such as biomass (wood and wastes), water mills, and wind power. Following the onset of the Industrial Revolution, with advancements in transportation technology and increased rates of deforestation in many regions, societies increasingly relied on long-distance shipments of coal, wood, and eventually oil, natural gas, and electric power. (more…)

Flex Fuel Vehicles Auto Industry Ford, Chevrolet, Honda, Toyota, and Nissan

Because transportation is such a large contributor to global warming, both globally and in the United States, climate and energy experts say finding clean alternatives to gasoline is also key to replacing fossil fuels and slowing global warming. Just as there is debate and competing research about which type of alternative transportation fuel should be developed to produce electricity, however, there is also competition among possible new transportation fuels. So far, in the United States, significant funding has been put into two transportation technologies—ethanol and hydrogen fuel cells. Many energy commentators say cars powered by electric batteries are the technology closest to mass production capability, however. (more…)

Hydrogen Fuel Cell Technology: Is It Efficient & Emission Free?

With ethanol’s future uncertain, many commentators see the transportation debate evolving into a war between two other technologies—hydrogen-powered fuel cells and battery powered electric vehicles. Some alternative fuel advocates are putting their support behind hydrogen, the most abundant element on Earth. Water, for example, is composed of hydrogen and oxygen molecules. Hydrogen can be produced from water by electrolysis, which separates the oxygen from the hydrogen. It can be used to power hydrogen fuel cells for vehicles (or to provide heat and electricity for buildings). Hydrogen fuel cells work by recombining hydrogen and oxygen—a process that produces electricity, heat, and water. Hydrogen-powered cars, therefore, could be an ideal transportation solution—nonpolluting, zero-emission vehicles that release only water, a natural and completely safe waste product. Also, fuel cells are highly efficient and powerful, and unlike typical batteries, fuel cells will never lose their charge as long as hydrogen fuel is supplied.

Hydrogen fuel cell technologies, however, must overcome many stubborn challenges before they can become a practical source of energy. Perhaps the biggest obstacle is cost; it currently takes more energy to make hydrogen than is produced, and production relies on expensive catalysts made from platinum, a scarce metal. And like biofuels, hydrogen is currently made using fossil fuels, so it is not emissions-free. In addition, liquid hydrogen fuel is highly flammable and must be stored at very low temperatures or under very high pressure, making transport and storage difficult. Switching vehicles to hydrogen fuel cell power also would require building a whole new infrastructure similar to the chain of gas stations that currently dot the landscape. Researchers are hoping to find answers to these problems by searching for other types of catalysts, studying other ways to improve production, and developing better hydrogen storage options.

Hydrogen researchers, however, have been promising breakthroughs since the 1990s with little progress to show for their efforts. Many observers are thus coming to the conclusion that the hydrogen fuel cell is a technology that will not be perfected in the near future. As physicist and climate expert Joe Romm explains, “Neither government policy nor business investment should be based on the assumption that these technologies will have a significant impact in the near or medium-term.” The Obama administration apparently agrees; it submitted a budget for 2010 that sharply cut back on government support for hydrogen projects. U.S. Energy Secretary Steven Chu explained the administration’s problems with hydrogen technology:

Right now, the way we get hydrogen primarily is from reforming [natural] gas. That’s not an ideal source of hydrogen. . . . The other problem is, if it’s for transportation, we don’t have a good storage mechanism yet. Compressed hydrogen is the best mechanism [but it requires] a large volume. We haven’t figured out how to store it with high density. What else? The fuel cells aren’t there yet, and the distribution infrastructure isn’t there yet. So . . . to get significant deployment, you need four significant technological breakthroughs. That makes it unlikely

Congress promptly reversed President Obama’s decision, however, restoring more than $200 million to 190 hydrogen projects around the country.

Wireless Power Transmission and Solar Power Satellites

Approximately 40% of Earth’s population is ‘‘off the grid,’’ mainly in developing countries. Wireless power transmission envisioned by Nikola Tesla a century ago is feasible today. Microwave beams can propagate power efficiently along lines-of-sight over long distances. Orbiting microwave reflectors could form the basis of a global electric grid.

An advanced technology path to electrification is the solar power satellite (SPS) proposed by Peter Glaser. Solar flux is about 10 times higher in space outside Earth’s shadow cone than the long- term average at the surface of spinning, cloudy Earth, and power from space can be beamed by microwave efficiently through cloudy skies to the surface where it is needed. (more…)

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