HAWTs and VAWTs

There are two basic types of wind turbines defined by the orientation if the axis or drive haft that turns the generator – horizontal axis wind turbines (HAWT) and vertical axis wind turbines (VAWT).

Horizontal axis wind turbines are the oldest, most efficient and therefore, the most common of the two types. They consist of two or more vertical blades (three is the most common) attached to a hub which is in turn attached to the horizontal drive shaft and the generator. This whole assembly sits on top of a tower. The blades face into the wind on the windward side of the tower to avoid any disturbance the tower may create. The tower is designed to elevate the blades into the strongest and most consistent wind. Currently, the longest blades are 82 metres long (269 feet) and the tallest towers reach 180 metres or 590 feet.

There are many different vertical axis wind turbine designs, ranging from the Darrius “egg beater” configuration to bladed turbines. Like HAWTs, vanes or blades turn a shaft connected to a generator , although in this case the shaft is vertical and the generator on the ground. There is no tower, and VAWTs  are generally much shorter than HAWTs, The prime advantage of  VAWT configuration is that it faces always faces into the wind, and is therefore better suited to areas where the wind is continually changing direction. Because of their more compact design, VAWTs are commonly used for microgeneration by home, cottage and small business owners and farmers to provide power for their own use or to sell back to grid.

A new development combines a VAWT with solar cells to provide electricity from wind power and solar power at the same time.

Ontario Pours Cold Water on Offshore Wind Farms

Offshore wind farms are viewed as one answer to wind turbine noise, unsightliness, and danger to bats. Makes sense? – put them where no one can hear or see them. As well, offshore winds are far more consistent and reliable than onshore winds. There are more than 40 offshore wind farms in China, Japan and 10 European countries. Their total combined capacity at the end of 2009 was almost 2,000 megawatts. So the question is why aren’t there offshore wind farms in Canada?

The answer is obvious for Alberta and Saskatchewan – neither have an offshore. Sure there are some big lakes but those are well off the grid and the costs of transmission infrastructure and transmission itself would be prohibitive.

British Columbia may soon have an offshore wind farm. On March 17, 2011 NaiKun Wind Energy Group was “granted a federal screening decision, confirming that Canada’s first offshore wind project can be constructed with no significant environmental, social or health effects.”  The project will be located in Hecate Strait Haida Gwaii and Prince Rupert and will comprise up to 110 turbines will a combined installed capacity of 396 megawatts.

Image: Naikun Wind Energy Group

While Ontario doesn’t have a sea coast, it does border on three great lakes: Ontario, Erie and Huron. Until recently four offshore projects were planned, but in February, the Ontario government decided to impose a moratorium “until the necessary scientific research is completed and an adequately informed policy framework can be developed.”  The ministry also said “Offshore wind power development in freshwater lakes is relatively new and presents technical challenges that do not exist in a saltwater environment, such as the need to manage potential impacts to drinking water and the effects of ice build-up on support structures.”

The action be the Ontario government seems to be counter to its previous assertions that wind power will be a more and more important source of electricity as the province’s coal-fired generating stations are phased out.

There is one other example of a wind farm in fresh water, the Vindpark Vänern on Lake Vanern in Sweden. Located 6.5 kilometres off shore and consisting of 10 three-megawatt turbines, the project went on line in May 2010.

While New Brunswick, Prince Edward and Nova Scotia currently do not have offshore wind farms, all three provinces are investigating the possibility.

Wind on a Global Scale

As with pretty much every great discovery, the initial use of wind power was probably accidental. Someone standing on a raft put out their arms, the air current caught their cloak and presto, the wind had been harnessed.

Initially, using the wind was more a case of redirecting it – into sails for transportation, through ducts and pipes for ventilation. Later, some enterprising person figured out how to power machines, like water pumps and grain mills with the wind.

It wasn’t until 1887 that a Scotsman named James Blyth first used wind-generated electricity to light his summer home. Later the same year, Charles F. Brush made a horizontal axis wind turbine that powered his house and laboratory in Cleveland, Ohio.

Left: James Blyth’s vertical axis wind turbine   Right: Charles Brush’s horizontal axis wind turbine.

Wind powered generators grew in popularity, primarily on farms or isolated buildings not connected to the grid. Capacities of these early generators was usually in the range of five to 10 kilowatts.

In the late 1970s, capacities increased to 20 to 30 kilowatts and the market expanded, especially in Europe. In 1980, the first wind farm was built in New Hampshire and comprised 20 30-kilowatt turbines. However, the project failed because of design errors. Never the less, it paved the way for successful projects soon after. The largest on shore wind farm in the world is the Bigelow Canyon Wind Farm in Oregon. The project consists of 217 wind turbines with a combined installed capacity of 450 megawatts. The site covers 100 square kilometres.

The first offshore wind farm was constructed at Vindeby, Denmark. It consists of 11 450-kilowatt turbines with a combined installed capacity of 4.95 megawatts. The largest offshore wind farm is Thanet, off the southeast coast of England. Covering 35 square kilometres, it comprises 100 three-megawatt turbines with a combined installed capacity of 300 megawatts.

Thanet Offshore Wind Farm Image: Vattenfall

The total global installed capacity is more than 200,000 megawatts, and individual turbine capacity has risen to seven megawatts. The top five producers are the United States (28.3 per cent), Germany (14.4 per cent), Spain (13.9 per cent), China (10.0 per cent) and India (6.1 per cent). Canada ranks 13 overall with 1.4 per cent.

In Denmark, wind generation accounts for 18.7 per cent of total electricity generation. Portugal ranks second with 15.5 per cent and Spain ranks third with 12.6 per cent. In Canada, wind power contributes less than one per cent of total electricity generation.

“The answer is blowin’ in the wind”

Could the final words of Bob Dylan’s 1963 classic Blowin’ in the Wind, become a mantra for Natural Resources Minister Lisa Raitt? It certainly came across that way in her opening remarks to the 25th annual Canadian Wind Energy Association conference and trade show in September. By year’s end, wind generation capacity in Canada will top 3,000 megawatts and Raitt evidently sees this burgeoning industry as a key to enhanced energy security as it boosts the economy and creates jobs. It’s the output of nearly 100 commercial wind farms already in place. Contrast that with the mid-1980s ago when there were none.

“I can’t think of very many industries that can show that kind of growth,” Raitt said. “Wind will be . . . lighting up hundreds-of-thousands of Canadian homes and doing it without generating a single kilogram of greenhouse gas emissions. . . . It’s good to be able to look back on how far the wind industry has come in this country — and it’s also a good time to look at where it’s going.”

This year will see British Columbia and Newfoundland & Labrador commemorating the opening of their first commercial wind farms and the minister said Canada’s fundamental vastness presents tremendous opportunities, not only for wind power but also other forms of energy.

“We have the opportunity to become a living laboratory for the rest of the world,” she said. “Every province has access to wind power and this is integral for us moving forward. . . . Wind energy continues to be a priority for the Government of Canada. It has to be; we’ve made a commitment to having 90 per cent of Canada’s electricity come from clean and renewable sources by 2020.”

Out of its $1.5-billion ecoENERGY for Renewable Power program, Ottawa has invested in 75 “and counting” projects. Two-thirds are for wind power. Raitt said this is being complemented by research and development at the Wind Energy Institute of Canada and other initiatives, including accelerated capital cost allowances for machinery and equipment, elimination of tariffs on imports of machinery and equipment, improved credit facilities, and the Green Infrastructure and Clean Energy funds.

The application deadline for another federal initiative, the $200 million Fund for Renewable & Clean Energy System Demonstrations, closed in mid-September and the government now is assessing 175 proposals for projects with a total installed value of some $3.5 billion. Eighteen are for both wind and electrical storage projects and Raitt said the government hopes to begin financing discussions with a short list of project backers shortly.

“The sooner we can get these projects running, putting shovels in the grounds and using this new technology, the closer we are to reducing our emissions and achieving our 2020 targets.”

Wanted: super batteries – mere mortals need not apply

Solar and wind power are fantastic energy alternatives to non-renewable fossil fuels. But as everyone knows, they only work when the sun is shining or the wind is blowing. So far, wind and solar count for only 3 percent of the energy needs in the United States. But with plans to increase wind power supplies to 25 percent by 2025, a reliable and stable back-up is essential.

Enter Plan B. Plan Battery, that is.

A small wind farm in Luverne, Minnesota is leading the charge with the nation’s first wind-to-battery setup. It uses the wind to charge batteries that in turn release the wind power onto the grid.

These aren’t your typical double-A batteries. They are super-batteries the size a double-decker bus, complete with mask, cape and superpowers. Though they can’t leap tall buildings in a single bound, they certainly can power them.

A Super Battery can soak up 7.2 megawatt hours of power with help from his trusty sidekicks: Wind Turbines. The superhero team belongs to MinWind, a Minnesota wind-power developer.

Overseeing the entire super battery project is Xcel Energy, a Minneapolis-based utility, which bought the batteries from NGK Insulators, a Japanese battery supplier. The reason? A year ago, their wind capacity was at 2,700 megawatts compared with about 3,000 megawatts today, an amount it hopes to double by 2020.

Research is being done to see how much power the sodium-sulfur battery system can absorb, how quickly, at what cost – and then deliver it to the grid.

It’s a bird, it’s a plane. No – it’s Super-battery!

Image: XCel Energy

Energy in your backyard

Renewable energy is the talk of the town, but how do you go about transforming talk into action? Sometimes it’s difficult to create change on a mass scale, but the more individuals think, talk and act according to increased awareness about the environment, the closer we all get to a more sustainable future. If you’re thinking about doing your part, two energy resources you should learn more about are solar and wind.

Catch some rays

Solar power can be used to heat water in your home or business and generate electricity for lighting and appliances. In addition to saving you money on your energy bill, power produced from the sun can provide an energy source in remote locations and increase security from power outages.

Think solar energy is a bright idea? The Canadian Solar Industries Association (CSIA) works with individuals and organizations to develop and implement programs that encourage the widespread use of solar energy in Canada. They offer a searchable member directory that is your best source for a full range of solar products (including solar panels and heat pumps) and services in your region.

They also provide information to help you learn to design and install solar photovoltaic systems and hot water systems and sponsor Clean Energy Classrooms where you’ll find additional employment and career information.

Have some questions or just need more information to get started?

NRCan’s ecoENERGY Renewable Heat program offers incentives to business to install active energy-efficient solar air and/or water heating systems. And on the home front there are government programs to help you pay for retrofits and renovations. These programs run to March 31, 2011. First Look helps you estimate annual solar radiation in your area. And Off the Grid seminars help you learn how to reduce your energy bill without changing your lifestyle. 

Got wind?

Wind power is a clean, sustainable source of energy. It is compatible to use with your regular power supply and is an excellent source of energy for rural areas. Ideal for less sunny regions, wind can generate energy day and night and is an inexpensive source of alternative energy.

Want to join the winds of change? Canadian Wind Association (CanWEA) represents the wind energy community in Canada — organizations and individuals who are directly involved in the development and application of wind energy technology, products and services.

CanWEA provides information on small wind energy systems. Their Small Wind Purchase Guide (472KB PDF) gives homeowners, ranchers and farmers helpful tips on buying wind turbines, assessing a site, permitting, installing and maintaining equipment and connecting to the grid. They also provide an easy step-by-step planning exercise and a cost calculator. If you’re looking at the bigger picture and want to learn more about wind farms and wind energy CanWEA can provide you with what you need.  

Have some questions or just need more information to get started?

First Look helps you estimate annual wind speed in your area. NRCan’s Clean Energy Project Analysis Software helps you evaluate energy production and savings, costs, emission reductions, financial visibility and risk for various types of renewable energy and energy efficient technologies. The Wind Energy Institute of Canada is advancing the development of wind energy in Canada through research, testing, innovation and collaboration. They have initiated a testing program for small wind turbines that includes power performance and quality, acoustic noise emissions, duration and safety. And Mariah Power is taking a new approach with a vertical wind turbine that supplies low cost energy and easy maintenance for your home or small business.

Bird-proof wind turbines under development

The debate on how best to maximize green energy and protect wildlife continues to be the source of turbulent debate, at least when it comes to wind power and the deadly interactions with birds and bats.

Relatively speaking, wind turbines are a negligible threat to birds and bats, compared to say, cats. But bird groups advocate for better-sited wind farms in order to lessen the impact on wildlife, prompting scientists to seek ways to essentially bird-proof turbines.

Location, location, location…

The problem with wind farms is that the locations are chosen for the same reason that birds and bats choose their migratory flight paths: the wind. Birds follow the winds because it creates less turbulence than hilly, or tree- and city- covered land, which results in an easier, faster and smoother flight…which puts them right in the path of the wind farms.

Wind turbines have come a long way in the last 25 years. The former ‘lattice’ design of towers used back then provided perches which actually attracted birds to the blades. The wind turbine blade configuration and size, and reduced speed of new designs have had the effect of lowering mortality rates. Though not as effective as the horizontal design, the vertical spires may be a good compromise.

Today scientists, wind companies, and environmentalists are working together to bird-proof the turbines. There are already bird-safe home wind turbines. And for the past several years, wildlife biologists have been observing and measuring the interactions of migratory birds and lake-anchored wind turbines.