Technology: Why wave power?

Ocean waves represent our planet's last untapped natural renewable energy resource. Over 70 per cent of the earth's surface is covered with water. The energy contained within waves has the potential to produce up to 80,000TWh of electricity per year - sufficient to meet our global energy demand five times over. The potential to capture energy from the sea offers a vast and endless source of clean sustainable electricity.

Predictable by nature

Ocean waves are generated by wind passing over the surface of the sea - a process which often begins many hundreds or thousands of miles from shore. Because waves originate a long way from shore, computer models of wave propagation allow us to accurately forecast incoming waves up to five days in advance.

In comparison with wind energy, it's easier to accurately predict how much energy can be generated by waves, and when. In addition, the peaks and troughs of wind and wave energy do not always coincide. This means there are times when there is abundant wave energy and little wind. This diversity helps even out the fluctuating nature of some renewable energy sources. When combined with other renewable energy, such as hydro power, it helps provide a more predictable and steady renewable energy mix.

A diverse renewable energy portfolio means a more stable energy system, reduced variability and lower cost. In addition, a strong renewable energy mix means we become less reliant on traditional power sources such as oil and gas. This gives us greater energy security.

Minimal environmental impact

Wave energy is, by its nature, a clean energy resource. Aside from the energy expended in manufacture and installation of wave energy devices, it produces no carbon emissions. Our industry is still very new but studies undertaken to date show the process of capturing wave energy has minimal environmental impact. Our Oyster device, for example, is a simple, slow-moving buoyant flap. This flap moves backwards and forwards in the waves and pumps water ashore. There is no electricity production or fast moving equipment at sea. And as Oyster uses freshwater as its hydraulic fluid it means there are no hydrocarbons in its system. The device sits largely underwater so there is minimal visual impact.

Other applications

There is an obvious link between wave energy and desalination - the process of removing salt from water to produce freshwater. There are a number of island groups, such as the Canary Islands, which receive little rain or have limited means to capture and store rainfall. Instead seawater must be desalinated by a technique known as reverse osmosis. Energy fuelled by diesel generators is used to pump high pressure saltwater over special membranes to produce freshwater.

Our Oyster device offers a cleaner, more cost-effective solution. Oyster could be configured to produce high pressure saltwater direct to a desalination plant, without the need for fossil fuels whatsoever.

Source :
http://www.aquamarinepower.com/technology/why-wave-power/

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Biofuel for the US Air Force

The US Air Force is ready to switch to biofuels to help power its warplanes but the price of alternative fuels remains too high, military officials said.
Anxious to reduce its reliance on oil, the Air Force has approved the use of synthetic fuels for nearly all its aircraft and expects to get the green light for biofuels by the end of 2012, Undersecretary Erin Conaton said.

“The big thing we’re trying to do is to send a clear message to industry that the Air Force wants to be in a position to purchase biofuels and to use that operationally for our fleet,” Conaton said.

“But in order to do that,we need industry to be able to produce in the quantities we need at a cost-competitive price.”

Biofuels cost a prohibitive $35 a gallon (3.8l), about 10 times the price of conventional jet fuel, or JP-8.

Performance

“The biofuels that are available now are just nowhere near the cost of what we can buy JP-8 for,” Conaton said.

With the biofuels industry still in need of more private investment, the US military has joined forces with commercial airlines “to try to send the right message”to the alternative fuels industry, she said.

“We’re ready whenever they’re ready to produce it.”

Tests have shown fighter aircraft and cargo planes can fly on a blend of biofuels and traditional jet fuel with no sacrifice in speed or performance, she said.

Conaton spoke as biofuels industry representatives and military officials gathered for an energy conference on Tuesday in Washington where alternative fuels will feature high on the agenda.

US officials see the country’s dependence on foreign oil as a national security risk and an increasing financial burden.

To promote energy “security”, the Air Force has set a goal to have half of its domestic fuel needs drawn from alternative sources by 2016.

The biofuels tested on military aircraft, known as hydro processed renewable jet fuel, are derived from the camelina plant, animal fat and various waste oils.

The military and commercial airlines are also testing “alcohol-to-jet”fuel produced from cellulosic feedstock,including switch grass,grains and sugar.

Conaton said the Air Force had plans to test the ATJ fuel on A-10 ground attack aircraft.

Following the Air Force’s lead, the Navy and Army are also working to promote the use of alternative fuels in ships, ground vehicles and bases, with Navy Secretary Ray Mabus arguing that the military can help generate enough demand to lower the price of biofuels.

Mabus told NPR earlier this month that “if we establish the market, the price is going to begin to come down”.

The Air Force’s consumption of fuel is equivalent to a major commercial airline, or about 10 billion litres a year.

Source : http://www.eco-h2o.co.za/2011/07/20/biofuel-for-the-us-air-force/

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What is wind energy?

Introduction
In just a few short decades wind energy has matured dramatically, making wind one of the fastest growing sources of electricity in the world today. Due to technological advancements, policy initiatives, and economic drivers, wind energy is now able to make a cost-competitive contribution to our growing energy needs.

Wind Turbine Technology
Turbines today are sleek and slender machines, a far cry from their wooden ancestors. Around the world, wind turbines of all sizes have become a familiar sight; ranging from home or farm-scale machines of 1 kilowatt (kW), all the way up to arrays of large 7 megawatt (MW) machines for off-shore use.

Modern wind turbines are up to the task of producing serious amounts of electricity. A popular sized machine in the U.S. today is a state-of-the-art 2 MW turbine that stands as tall as a 30-story building and costs roughly $2 million to $5 million installed. With a good wind resource, this size turbine can produce 5 million kWh of electricity each year, or enough energy to run 500 average American households.

Wind Energy Around the Globe
Turbines are sprouting up around the globe in record numbers. By the end of 2010, there were over 197,000 MW of wind installed around the world, which is more than three-times the 59,000 MW installed in 2005. The pace of growth is now greatest in China, where installed wind energy capacity grew by 18,928 MW in 2010, over half of their total 25,805 MW installed capacity. Yet the United States leads the world in total installation, with 35,086 MWby year end 2010. The growth in the Chinese market put China second in total installed wind capacity with 25,805 MW edging out Germany (25,777 MW).

China's recent boom can be attributed to the passage of a Renewable Energy Standard in 2007 and the introduction in 2009 of requirements for grid owners to buy electricity from renewables, as well as a 20-year feed-in-tariff for wind projects. While nearly half of the world's new installed capacity in 2010 came from China, other countries are also growing their wind resources. (Source: Global Energy Council's Global Wind Report 2010).

Spain continues to be a leader in wind power, with India, France, Italy and the UK rising in the market. The recent boom in renewable energy investment, including wind energy generation, is being aided through progressive policies and widespread public support. Legislation such as the UK's Renewables Obligation, the 29 US states and 2 territories with Renewable Portfolio Standards, and the EU's target for 20% renewable energy by 2020 is aiding the development of wind energy across the globe.

Wind Energy in the United States
Total wind capacity in the United States reached 46,919 MW by the end of 2011, with commercial-scale wind turbines operating in 38 states. Wind power accounted for 35% of the country's new power-production capacity from 2007 to 2011, second only to natural gas. According to the American Wind Energy Association (AWEA), Texas leads the country as the state with the most installed wind power with 10,135 MW. Iowa remains a leader in wind generation with 3,675 MW installed; while California and Minnesota continue to harvest significant amounts of wind with 3,179 MW and 2,432 MW respectively.

Although this is significant growth for wind energy, it still only accounts for a small percentage of the U.S. electricity supply. The U.S. Department of Energy recently released a report that laid out a plan to reach 20% wind energy power by 2030 to fuel the U.S. electricity grid. This would provide a major increase in jobs, benefits to rural landowners, and lead the Country to increased energy independence. Factors pushing for growth in U.S. wind energy include the high cost of fossil fuels and concern over national energy security. As a result, policy makers are actively considering a wide range of legislation that would support and enhance wind energy growth.

Progressive public policy has usually been a key ingredient both for encouraging wind energy expansion and helping to determine what forms that growth will take. Future growth will likely come from commercial-scale wind farms, which are typically vast arrays of turbines owned and operated by large corporations. Yet experience in Minnesota has shown that, with an encouraging policy environment, small clusters of turbines or even single turbines can make significant contirbutions, operated by local landowners, small businesses, and community wind projects.

The Future of Wind Energy
Technological advancements and supportive policy measures have the ability to dramatically increase the future of wind energy development in our nation and our world. Wind power has the unique ability to provide even greater sources of distributed energy production, which means less risk and a stronger energy portfolio. America’s ingenuity and drive for independence are well suited to increased wind energy development in the future. Stay tuned to advancements at industry and policy levels as wind energy continues to grow.

Source : http://www.windustry.org/wind-basics/introduction

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