Yale Environment 360 has a look at the fast growing micro-wind sector - With a Boost from Innovation, Small Wind Is Powering Ahead.

The Solarium, a new 8-story apartment building in New York City, is part of a new wave of green buildings in Gotham. Its exterior is made from 100 percent recycled material. The burnished floors are sustainably farmed bamboo. The apartments lack bathtubs in order to save water. Perhaps the most novel green accoutrement of the Solarium, however, is a small, black windmill perched on a short pole rising from the rooftop. Made by WindTronics, the windmill went live in April — it is one of the early beta units from the Michigan startup.

The company claims a single windmill can supply as much as 30 percent of a household’s annual power needs if winds average roughly 10 miles per hour. That is a brisk steady breeze but even homes averaging lesser amounts (5-9 mph winds) can receive significant electrical outputs of 15 to 30 percent of annual power needs. The Solarium’s wind turbine will power light fixtures in common areas and a rooftop theater for residents. “It has no noise and no vibration,” says Cyrus Claffey, the CEO of Clareo Networks, a real estate technology and design company that researched and planned the project for the Solarium’s developers. “It is bird friendly. And it has a great design. Power kicks in at a much lower windspeed than comparable products.”

This WindTronics windmill represents a new wave of technology innovation sweeping through the small wind industry. This innovation combined with national, regional and local incentives, as well as significant cost reductions in installations and products, is driving fast growth for small windmill makers. In 2009, despite an abysmal economy, the U.S. small wind market (turbines with rated capacities of 100 kilowatts or fewer) grew by 15 percent, according to the American Wind Energy Association (AWEA). That growth included an increase of 20.3 megawatts of new capacity and $82.4 million in sales.

The 2009 tally pushed the total installed capacity of small wind turbines in the United States to 100.2 megawatts. (That’s only equivalent to one-fifth the output of an average coal-fired power plant in the United States. But more than half of that capacity came online in only the last three years, making small wind one of the fastest-growing renewable energy resources around.) This adoption is being driven by government incentives, improved zoning procedures, consumers’ growing affinity for residential clean energy, and emerging financing mechanisms. The 2009 American Recovery and Reinvestment Act expanded available federal investment tax credits for small windmills to 30 percent of the total cost of a wind system, an enormous boost that puts small wind on equal footing with the fast-growing residential solar industry.

“You can add the federal credit on top of state level rebates that can be 20 percent to 25 percent and that pushes the effective price of installing a small residential wind system down to $15,000 on average,” says Ron Stimmel, the legislative affairs manager for AWEA. With such a system, he notes, consumers are effectively pre-paying their electricity bills for decades. According to Stimmel, most windmills have a lifespan of 20 to 30 years.

To date, most of the growth in small wind in the United States has come in rural and semi-rural areas. This has been due to the requirement for many types of small windmills to sit atop poles that rise at least 40 feet above terra firma. Rural areas have long been more permissive of these types of installations. Looser zoning codes in those areas have allowed farmers to put up windmills without having to go through permitting hoops — or angering neighbors who might have to look at the spinning systems. Even in these types of rural regions, however, penetration remains below 5 percent and room for growth is enormous.

Some rural states have embraced wind at a policy level. Vermont, for example, became the first state to implement a feed-in tariff (FIT) for small wind systems. This tariff guarantees that small wind farmers can resell excess power back to the big utilities at above market rates.

According to AWEA, roughly half of all small wind power additions in 2009 were in the U.S., and the country has more than three times as many small wind manufacturing companies as the next closest competitor, Japan. While the U.S. may lead in small wind innovation, the rest of the world is looking to catch up. Japan, Canada, the United Kingdom, China, Germany and Holland all have significant numbers of small wind technology companies.

At present, the United Kingdom and Canada have the most well-developed small wind markets outside of the United States. But 33 countries have put in place FITs for small wind power generated by homeowners and small busineses who wish to sell their power back into the grid. Such tariffs are designed to promote the installation of smaller scale renewable power projects. These countries include most of the developed world and emerging giants such as China and India, but also a number of developing economies including the Philippines and Kenya. International policy and finance bodies are pushing hard to bring small wind systems to isolated rural communities, particularly as a complement to solar installations. The World Bank has undertaken an aggressive program to push small wind to developing nations in South America, Asia and Africa as part of its Renewable Energy in the Rural Market initiative. ...

The arrival of more advanced systems, like the WindTronics device, could herald deeper penetration into urban areas previously considered unusable due to the chaotic nature of the breezes and the long periods of relative low winds. The WindTronics system, which resembles a fancy racing bike wheel, is vibration- and noise-free. Birds readily recognize the windmill, and it can be installed on a rooftop, eliminating the need for tall, unsightly poles. More importantly, according to WindTronics, it begins to generate power at wind speeds as low as two miles per hour, five miles per hour less than more traditional windmill designs, and it can continue to generate power at wind speeds as high as 42 miles per hour, nearly 15 miles per hour higher than standard shut-off speeds for most wind turbines.

Inhabitat has a post on a Nikolai Tesla inspired wind turbine design - Ultra-Efficient Bladeless Wind Turbine Inspired by Nikolai Tesla.

SolarAero recently unveiled a new bladeless wind turbine that offers several advantages over current wind turbines — it emits hardly any noise in operation, has few moving parts, and since it doesn’t use spinning blades it’s much less of a hazard to bats and birds. The whole assembly is inside an enclosed housing, with screened inlets and outlets to keep animals safely out. It also can be installed on sensitive locations such as radar installations or sites under surveillance where the rotating blades cause detrimental effects. Read on to learn what makes it work.

Whether they are vertical axis or horizontal axis, typical wind turbines work by catching moving air with blades, and using that force to rotate the axle, which turns a generator to produce electricity. Instead of pushing on blades, SolarAero’s turbine is based on the Tesla turbine originally developed by Nikolai Tesla. The principle of the Tesla turbine is to set up an array of closely-spaced, very thin, and extremely smooth metal disks. The viscous flow of air moving in parallel to the disks is what propels the turbine, instead of buffeting blades with moving air. This makes for a more compact mechanism with only one moving part: the turbine-driveshaft assembly.

According to the company, this turbine should cost around $1.50 per watt of rated output, and have a lifetime operating cost of about 12 cents per kilowatt-hour — comparable to, or even better than, current retail electrical rates in many parts of the country. This would make the SolarAero turbine about 2/3 the price of a comparable bladed unit, and because of the significantly lower operating costs, lifetime maintenance could be just 1/4 the cost. At this point the project is still under development, and no manufacturer has been lined up as of yet.

Inhabitat reports that micro-wind turbines are starting to be seen on corporate buildings - Adobe Headquarters Installs 20 Vertical Axis Wind Turbines.

Eventually, we’ll be squeezing renewable energy out of every possible source we can – especially from rooftops in urban areas. Adobe Systems is at the forefront of this trend, having just installed building integrated wind turbines atop its headquarters in downtown San Jose, CA. Their 20 new Windspire vertical axis turbines are affixed on the 6th floor of the parking garage of their office complex, which also happens to be LEED certified. The electricity generated from the turbines will eventually power an electric vehicle charging station in the garage below as well as the famous San Jose Semaphore!

Mariah Power is the maker of the Windspire, which weighs about 650 lbs, stands 30 feet tall and has a rating of 1.2 kW. Adobe installed 20 of these turbines around its employee basketball court at the top of its parking garage. Surrounded on either side by two Adobe office towers, a wind tunnel effect is created above the garage and gets average wind speeds of 14 mph. Adobe and Mariah Power expect that each of the turbines will generate about 2,500 kWh annually, totaling up to 50,000 kWh for the whole system.

TreeHugger has a post on micro-wind power devices for the home - Hot Home Wind Turbines You Can Actually Buy, Plus One You Wish You Could.

Though solar panels definitely hog the renewable energy stage when it comes to home installations, a number of new, innovative wind turbines have entered the market in the past couple of months. Not all of these are intended to be mounted on your roof, some you’ll need a bit of a yard (and a dearth of neighbors) to install and they vary in price from affordable to "when am I going to actually pay this off?”, but they all go to show that there’s more than one way to harness the wind to generate electricity. Check 'em out...

Cleantech.com has a report on an unusual looking new small-scale wind turbine from Broadstar Wind Systems, who are claiming it can produce cheap wind power.

A stealth wind turbine company emerges claiming $1 per watt, but a competitor questions its technology.

Dallas, Texas-based BroadStar Wind Energy today emerged from stealth at WINDPOWER 2008 and revealed its AeroCam Turbine, which it claims can be deployed almost anywhere—including urban environments—and to the competition's chagrin, at a cost-effective $1 per watt installed.

Five years in the making, the AreoCam was designed for commercial applications and aims to compete with large solar rooftop installations and looks to be included in existing wind farm installments. According to serial entrepreneur and CEO Steve Else, BroadStar is an attractive alternative to solar where the getting energy from the sun isn’t an option.

What if there’s not enough wind? Else says that’s not a problem. “Our installations are at the concentration of flow at the power pit of a building. We can achieve a 30 per cent increase of the speed of the wind at the line of the power pit,” says Else. “The sun doesn’t shine everywhere, but the wind doesn’t blow everywhere either.”

With the U.S. Department of Energy issuing a report last month stating that the wind industry growth in the U.S. could be more successful with governmental incentives (see Wind power push could depend on incentives), this year's WINDPOWER conference set on proving the industry will charge agressively forward.

To provide the industry further fodder for growth, a wind vendor survey by Germany's Husum WindEnergy suggested the industry expects to grow extensively over the next several years and anticipates 170,000 MW of wind turbines to be installed—up from a reported 20,000 MW in 2007.

While BroadStar is barely entering its pilot stage, Else is convinced that once his turbines are deployed and certified, they’ll have a lot of turbines in places where conventional technology cannot be deployed due to the scale of equipment involved.

Currently BroadStar says it is in final negotiation for pilot programs for two Fortune 100 companies and hopes to have a total of six pilot programs across different industries this year. “The initial pilots are in the 40 KW range,” says Else. ...

Other wind medium-to-small turbine equipment companies include Southwest Windpower, Bergey Windpower, Solar Wind Works and Entegrity Wind Systems, just to name a few.

BroadStar’s AeroCam, which was designed with airplane wings in mind, promises to pick up the wind drafts that hit buildings and then move upward-catching currents as gentle as 4 mph in excess of 80 mph.

BroadStar says these turbines are ideal for both the urban and suburban settings and are ideal for high and low-rise buildings, commercial rooftops and parking structures, warehouses, and shopping malls and elsewhere.