The Alternative Energy blog – green renewable alternative energy

A sycamore seed design may be set to revolutionize the wind power industry.

British engineers have designed a giant wind turbine called the Aerogenerator that would rotate on its axis mimicking the way sycamore seeds fly.

The Aerogenerator has two arms coming out of its base to form a V-shape, with rigid “sails” mounted along their length.  The arms act like aerofoils as the wind passes over, helping to generate lift.

It would measure nearly 900 feet from tip to tip and could generate 20MW or more of power.

Engineering firm Wind Power Limited is developing the Aerogenerator, along with architects at Grimshaw, academics at Cranfield University and Rolls Royce, Arup, BP and Shell.

The first Aerogenerator could be up and running by 2013.

Feargal Brennan, head of offshore engineering at Cranfield University, says “Upsizing conventional onshore wind turbine technology to overcome cost barriers has significant challenges, not least the weight of the blades, which experience a fully reversed fatigue cycle on each rotation.”

“As the blades turn, their weight always pulls downwards, putting a changing stress on the structure, in a cycle that repeats with every rotation – up to 20 times a minute.”

“In order to reduce the fatigue stress, the blade sections and thicknesses are increased which further increases the blade self-weight. These issues continue throughout the device.”

“Drive-train mountings must be stiff enough to support the heavier components inside the nacelle on top of the tower, otherwise the systems can become misaligned and the support structure is also exposed to extremely large dynamic thrust and bending stresses, which are amplified significantly with any increase in water depth.’”

Wind power is now generating 2% of global electricity demand, according to the World Wind Energy Association.

The countries with the highest shares of wind energy generated electricity: Denmark 20%, Portugal 15%, Spain 14%, Germany 9%. Wind power employed 550,000 people in 2009 and is expected to employ 1,000,000 by 2012.

Globally 38,025 MW of capacity were added in 2009, bringing the total to 159,213 MW, a 31% increase. The graph shows the top 10 producers (with the exceptions of Denmark and Portugal) and includes Japan (which is 13th).

From 2005 to 2009 the global installed wind power capacity increased 170% from 59,033 megawatts to 159,213 megawatts.

Over the 4 year period the capacity in the USA increased 284% and in China increased 1,954%. China grew 113% in 2009, the 4th year in a row it more than doubled capacity. In 2007, Europe had for 61% of installed capacity and the USA 18%. At the end of 2009 Europe had 48% of installed capacity, Asia 25% and North America 24%.

Australia:

Small wind-energy companies fear privatisations of power stations and retailers in New South Wales and Queensland could weaken competition in the electricity market, hindering their capacity to contribute to the federal government’s 20 per cent renewable energy target.

Under the renewable energy target, retailers are required to buy or create enough renewable energy certificates (RECs), each representing one megawatt-hour of emissions-free electricity, to meet an annual target.

But because they are generators as well as retailers, AGL Energy and Origin Energy have tended to get the certificates through wind farms they have built themselves, according to The Australian Financial Review.

As a result, independent wind power companies such as Infigen Energy, Pacific Hydro and Canberra-based Windlab, can have difficulty locking in long-term supply contracts for the certificates they produce. Without a long-term contract, banks will not provide finance for a wind project.

“The reality is you need competition in the market place at a retailer level,” Windlab chairman Roger Price said. “I’d rather see four or five major retailers that are looking to purchase RECs rather than just two which are extremely vertically integrated.”.

One of the largest offshore windfarms in the world, is to be built off the coast of Wales in the UK.

The £2bn Gwynt y Mor windfarm will have 160 wind turbines around 10 miles off the north Wales coast near Colwyn Bay and Llandudno.

Gwynt y Mor will be Wales’ largest wind farm, capable of powering around 400,000 homes, and preventing the release of 1.7m tonnes of carbon dioxide every year.

The RWE Innogy-led project is expected to be completed in 2014.

It is claimed some 1,000 jobs could be created in relation to construction and the supply of components.

Welsh Secretary Cheryl Gillan said: “This is excellent news. Gwynt y Mor will be one of the single biggest private investment projects ever seen in Wales, creating up to 1,000 quality jobs and contributing many millions of pounds to the regional economy of north Wales.

“It will also become one of the largest offshore windfarm projects in Europe, able to provide enough clean, green electricity to power the equivalent of around 400,000 homes.

“In Wales we are ideally located to embrace the economic benefits of green technologies.

“Surrounded by wind, wave and tidal resources, we are in a prime position to be able to benefit from investment in the green economy whilst making a significant contribution to the [UK] government’s carbon reduction targets through safe, clean renewable means.”

TAKE a trip around emerging Asia these days and you won’t just see skyscrapers and coal-fired power plants growing out of places where there were once nothing but fields. Wind turbines, solar energy plants, incinerator manufacturers, water treatment plants and microirrigation developments are just as likely to spring up before your eyes.

There is now recognition in the region that sustainable growth requires tackling the environmental issues such as water scarcity and climate change that have arisen as a result of rapid population growth.

Fund managers looking for strong growth opportunities are increasingly targeting environmental and sustainable industries. Khiem Le, a manager of the Axa WF Framlington Global Environment Fund, says the opportunities in the sector mean it will enjoy plenty of demand from institutional investors, unlike other industries such as auto, media or even finance. Firms across the region such as Chinese smart meter provider Wasion, Indian microirrigation firm Jain Irrigation and Manila Water in the Philippines are benefiting as a result.

While the Axa fund is global, some funds are targeting the Asia-Pacific area specifically. Impax Asset Management launched its Asian Environmental Markets closed-end investment trust last October to do just that and Jupiter followed suit in mid-December with its China Sustainable Growth fund.

The Impax investment trust has a total fund size of £122.6m and its net asset value (NAV) has grown by 10.3 per cent since its launch. The four-month-old Jupiter open-ended fund is gently building up assets under management – it currently has around £19m.

These funds seek long-term returns, making them ideal for pension funds – the second biggest declared shareholder in Impax’s Asian Environmental Markets trust is the London Pension Fund Authority. The biggest shareholder is Invesco Perpetual, which is gaining from Impax’s environmental expertise and network in both the region and the sector. Both funds are looking to get in early and capitalise on emerging Asia’s long-term growth prospects.

Policy is also shifting, says Bruce Jenkyn-Jones, who manages the Impax fund: “We detected a sea-change in the approach of governments in the region to the [environmental] sector and the propensity to launch budgets and policies to support it.” For example, the past few years have seen Chinese wind turbine manufacturers becoming competitive with US producers, thanks in part to government support.

Fund managers looking at growing their exposure to Asian environmental markets should not try to find the perfect company. Philip Ehrmann, manager of the Jupiter China Sustainable Growth fund, says that in an environment which is so young and where there is so much change, you won’t find them. “We are seeking companies which make money as a result of becoming leaders in their fields and contributing towards sustainable growth,” he explains. “As they make progress, so do you and you can increase your exposure.”

Wind energy is both green and fun, so the idea of building one’s own wind turbine is a good one. The following will give you an idea of what is involved.

Wind energy on a large scale is now competitive with other sources of electricity on a commercial scale. However, small domestic-sized wind turbines have not yet reached this point. The wind is free, but small wind turbines are expensive in relation to what they produce, and cannot realistically compete with mains electricity. Building your own machine saves some of the cost, but please do not underestimate the difficulty of the task. If it were easy to save money by using small wind turbines, then they would be a major feature of the landscape by now.

Most residential locations are not suitable for windpower as trees and buildings break the force of the wind, and create turbulent gusts which can be very destructive. Open hilltop sites or coastal situations with unobstructed views may be suitable for siting a wind turbine. A very tall tower is helpful, but these are not always appreciated by your neighbours.

What size of wind turbine do I need?

Wind turbines work with thin air, so they need to be large in relation to the power they produce. To power a modern home on a good site, the blades would need to span about 5 metres from tip to tip. This is known as the rotor diameter. With careful conservation of energy a smaller machine may suffice. A rotor diameter of 2 metres might yield about 500 kWh of electricity per year, compared with an average annual household consumption of roughly 4,500 kWh.

What sort of generator should I use?

Most small wind turbines are used for charging batteries, to provide a reliable stand-alone power source where grid power is not available. The obvious choice of generator for self-build is the car alternator. However this has major drawbacks. It must be driven at a high shaft speed (over 2000 rpm) to give full output, so you will need to gear it up or modify it in some way to drive it with rotor blades, which typically only manage a few hundred rpm. This reduces the efficiency. In low windspeeds there is very little power available in the wind, and you need a highly efficient generator to capture it. Most, if not all of the power in light winds will be used up energising the magnetic field in the alternator, so the results are disappointing. Nearly all small commercial wind turbines use purpose-built permanent magnet generators for this reason. The DIY enthusiast can make one too, but this is not simple to do. Or you can reuse a permanent magnet motor as a generator. The generator is the key to success or failure of the project, and by far the hardest part to get right.

Can I make my own blades?

The good news is that yes, many beginners have made very useful wind turbine blades, often carved from wood. Or there are sources where you can buy them ready made. If you plan on making your own, it is well worth doing some research and finding out all you can about it in advance. Not only will this save you from ‘reinventing the wheel’ but it will also be safer. Safety is an important issue even with the smallest wind turbines. Never underestimate the destructive power of a runaway windmill rotor in a high wind. Make sure that you have built-in protection against all eventualities. Control systems are as important as any other part of the wind turbine.

Its not easy building your own wind turbine but with skill and dedication it can be very satisfying.

In just over a decade China is expected to become  the world’s largest producer and consumer of alternative energy, according to experts. 

China’s installed wind capacity has doubled in each of the past four years.

In addition, in just a little over four years, a mix of government and foreign investment has transformed the Chinesport city of Tianjin city into the global manufacturing hub of the world’s wind power industry.

The country also has one third of the global solar panel market.

Many experts now seem reasonably optimistic that China could meet its ambitious renewable energy plans to derive at least 15 percent of all energy from renewable sources by 2020. The country also is striving to reduce energy intensity per unit of GDP by 20 percent over a five-year period.

All this in a country  that has some of the worlds most polluted air and water.

Ironically the country is poised to be at once the world’s leader in alternative energy — and its leading emitter of C02. 

Alternative energy as a percentage of the total energy mix is increasing, but it will complement — not replace — growth in coal power. In fact, in a decade coal is expected to supply about 70 percent of China’s energy. Because of the sheer scale, diversity, and complexity of China, it is possible for the country to take some great green leaps forward while at the same time having its rivers remain black and its air quality a health hazard.

China is rushing forward with its wind energy plans with the pace surpassing even the most optimistic projections.

After setting an original goal of 30 gigawatts of installed wind power by 2020, the government recently said that could be raised to 100 gigawatts as installed capacity has doubled each of the last four years.

From almost nothing a few years ago, China had 12.2 gigawatts of installed wind power by the end of 2008 as power companies have rushed to meet government mandates to raise the proportion of energy they produce from renewable sources.

The wind energy industry has vigorously rejected new research from the US suggesting some residents living close to wind farms are susceptible to a collection of health risks dubbed “Wind Turbine Syndrome”.

Dr Nina Pierpont, a New York paediatrician, claimed this week that the noise and vibrations caused by wind turbines could impact the health of nearby residents. But the British Wind Energy Association (BWEA) accused the study of being based on an “unscientific” sample and running counter to wider-ranging research that suggests wind turbines do not pose health risks.

Dr Pierpoint said there was “no doubt” that her research showed that Wind Turbine Syndrome exists and that the infrasonic to ultrasonic noise and vibrations emitted by wind turbines caused about 12 different symptoms, including abnormal heart beats, sleep disturbance, headaches, tinnitus, nausea, visual blurring, panic attacks and general irritability.

However, according to a draft copy of the section of the book intended for non-clinicians that is available on Dr Pierpont’s web site, much of the research appears to be based on interviews with just 10 families living near wind turbines ranging in size from 1.5MW to 3MW, resulting in a sample of 38 people.

A spokesman for the BWEA said that the size of the sample group and the methodology for the study “simply does not stack up scientifically”. “This is research based on the symptoms of 38 unspecified people in a small number of unspecified locations,” he argued, adding that a recent, more extensive study by acousticians at Salford University had concluded that there were no health risks arising from the noise from wind turbines.

A New York paediatrician has warned that living too close to wind turbines can cause heart disease, tinnitus, vertigo, panic attacks, migraines and sleep deprivation in groundbreaking research due to be published later this year.

Following studies of people living near wind turbines in the US, UK, Italy, Ireland and Canada for the past five years, Dr Nina Pierpoint has identified a new health risk called wind turbine syndrome (WTS).

She says the disruption of the inner ear’s vestibular system by low-frequency noise from the turbines is causing problems ranging from internal pulsation and quivering to nervousness, fear, a compulsion to flee, chest tightness and increased heart rate.

To date, wind companies have denied any health risks associated with powerful noise and vibration produced by wind turbines, backed by recent research by acousticians at Salford University, who argue that earlier claims by Dr Pierpont are “imaginary”.

Scientific orthodoxy has been overturned by the discovery that like fish, humans are affected by vibrations through their ear bones, Dr Pierpont claimed.

“It has been gospel among acousticians for years that if a person can’t hear a sound, it’s too weak for it to be detected or registered by any other part of the body. But this is no longer true,” she said.

“Humans can hear through the bones. This is amazing. It would be heretical if it hadn’t been shown in a well-conducted experiment.”