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How Wind Power Works
Time 02:00
How Skystream Works
Time 03:35

Backyard wind power: Skystream 3.7 is the revolutionary new wind generator designed for utility-connected homes. Reduce your electric bills with clean, renewable wind energy.

Eco Tech: Powering Up
Time 07:36

Wind PowerTraditional wind turbines don't work in the Windy City.
DNA shaped turbines do.

Helix Wind Turbine
Time 02:31

Why Helix Works
Inexpensive, reliable, simple, the hallmarks of the Helix system make it the best choice for low wind speed residential and commercial applications. The Savonius turbine based design catches wind from all directions creating smooth powerful torque to spin the electric generator. Mounted up to 35 feet high, in winds as low as 10 mph the Helix system creates electricity to power your home or business.

How it works: As the wind blows the long helical blade scoops catch wind from all directions forcing it through the turbine. The turbine generator is connected directly to your home and as electricity is generated your home is powered. If the wind isn’t blowing your home is powered by the energy grid as usual. If the wind is blowing strongly then your energy produced can exceed your energy consumed and, depending on your local utility, your meter can spin backwards rolling back your energy bill.


PacWind - Delta 2 Silent VAWT
Time 0:17

PacWind's Delta 2 produces an average of 5kw, but if winds of 29mph are present it can produce up to 10kw. I am standing on the roof of our building which overlooks the Torrance Airport, there is a lot of noise pollution during the day from vehicle traffic, helicopters/airplanes and work projects down below. I am proud that our Turbine is completely silent.

A Wind Turbine - Rooftop
Time 1:39

New wind turbine design. Nine News 27th June 2007.
Australia, Perth W

Wind Turbine Vertical
Time 00:41

There are trees nearby and a taller building adjacent. The horizontal anenometer is Wind Turbine
Vertical there are trees nearby and a taller building adjacent. The horizontal anenometer is swivelling
around much faster. Even the horizontal turbine on the tower nearby is unable to hold a good angle


Click Here For Complete Article


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The Power and Potential of the Wind one of the power resources of the future

o How much energy is in the wind and how to get it out Wind is a very complex process which can be described very simply.

The sun heats the earth at different rates depending on whether an area is below clouds, in direct sunlight, or covered with water. The air above the warmer areas heats up, becomes less dense, and rises. The rising air creates a low pressure area. Cooler air from adjacent higher pressure areas moves to the low pressure areas. This air movement is wind.

People have been capturing the energy contained in the wind's movement for hundreds of years. Dutch-style windmills were first used in the 12th Century, and by the 1700s, had become a major source of power in Europe. In North America, farmers adopted windmill technology to pump water about a hundred years ago.

Today, the turning rotors of a wind energy system can still be used to run pumps, and to run a generator to generate electricity.

The wind is a renewable energy source, continuously generated or replenished by the forces of nature. Renewable energy technologies, such as wind energy systems and solar photovoltaic (PV) systems, which use sunlight, convert renewable resources into usable forms of energy that can complement or replace conventional energy sources.

Canada is a large country with a huge wind energy potential. Tapping into this potential will help decrease the amount of greenhouse gases emitted by conventional sources of energy.

Modern large wind energy installations are popping up across the Canadian landscape. These "wind farms" use an array of wind turbines, each generating around 600 kilowatts, and are hooked to the main electrical grid. While this is a promising technology, it would still take 1,500 of these large turbines to match the output of one CANDU reactor. On the other hand, if replacing an oil or coal generator, just one of these turbines could eliminate over 1,000 tonnes of carbon emissions per year.

This guide is aimed at those who are considering a wind energy system to supply energy to their homes, farms, cottages or businesses. In most cases, such small systems have capacities in the 100 watt to 25 kilowatt range.

At the low end of this scale, enough electricity is generated to run a few lights, a communications radio or entertainment equipment. At the higher end, many of the electrical needs of farm operations or institutional buildings could be met. Somewhat larger systems could also supplement municipal needs and supply power to remote communities.

While the tested technology of direct mechanical work, such as pumping water, will be touched upon in this guide, we will focus on electrical generation.

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Wind Energy energy! A Renewable Energy Project Kit The Pembina Institute

The sun has a lot to do with creating winds. Winds above continents and oceans occur because of temperature differences around the world. Some places, especially those near the Equator, receive far more direct sunlight than those closer to the Earth’s north and south poles. As a result, the air over these areas warms up and then rises. Cooler air from the surrounding area rushes in to fill the space left by the rising air, creating a surface wind.

Air is constantly on the move. In some places, especially along coastlines and in mountains, it provides a highly reliable source of mechanical energy. Humans have invented an amazing array of devices that can harness the energy of the wind and put it to practical use.

Sails One of the oldest uses of wind energy is transportation. The first primitive sails were probably made from woven mats held aloft by wooden poles or human hands. Modern sailboats have very efficient sails and masts constructed from strong, lightweight materials such as Kevlar (the material used in bulletproof vests) and titanium. They work like aircraft wings to generate forces that pull the boat in the desired direction. Pumping and Grinding Long before the invention of electricity, early wind turbines did very useful work.

Windmills were used in many places in Europe over the last several centuries to turn heavy granite disks called millstones. The millstones were used to crush dry grains such as wheat, barley, and corn to make flour or meal.

The Netherlands is famous for its windmills. In truth, most of these structures are not mills at all,but water pumps. The Dutch created new farmland along the coast by building dikes around low-lying estuaries and mudflats and pumping out all the seawater. The “windmills” provided a steady supply of mechanical energy to lift seawater into the canals, allowing the new farmland to dry out. Surface winds occur when sunwarmed air rises, and cooler air rushes in to fi ll the space left behind. Windmills have been in use in Europe for centuries. Capturing Wind Energy

In the past, windmills were common on farmsteads across Canada. They were often used to pump water from wells to watering troughs for cattle and to generate electricity at the farmhouse. When rural areas finally received electricity, many of these windmills fell into disuse and disrepair. Recently however, small windmills are becoming popular once again for bringing water to livestock.

Generating Electricity
One of the most popular uses of wind turbines is to generate electricity. To make electricity, the shaft of the turbine must be connected to an electrical generator. Through gearboxes, the generator converts the mechanical energy of the spinning turbine shaft into electricity. Generators are small and light enough that they can be housed under an aerodynamically designed cover at the top of the pole or tower. Wires running down the tower carry electricity to the grid, batteries or other appliances, where it is stored, and/or used. Electricity is now being generated on a commercial scale at large installations called “wind farms” in severalplaces around the world. Wind farms consist ofrows of towers, sometimes 90 metres high, equipped with giant wind turbines for producing electricity. In Canada, the first commercial wind farm was built in southern Alberta near the town of Cowley, in a region famous for its strong, steady winds. Commercial wind farms have also been established in Germany, Denmark, the United States, Spain and India. Denmark and Germany have pioneered the development of commercial wind power, one of their fastest-growing industries. Wind turbines are gaining popularity with cattle ranchers for watering their livestock.

Some companies are now installing wind farms in shallow waters near coastlines in small countries with little available land area. These “offshore wind farms” are a promising new source of electricity. Toronto Hydro is installing such a turbine offshore on Lake Ontario.

Commercial wind energy is one of the most economical sources of new electricity available today. Wind turbines can be set up quickly and cheaply compared with building new coal-fired generating stations or hydroelectric facilities. Modern wind generating equipment is efficient, highly reliable, and becoming cheaper to purchase. The environmental impact of large wind turbines is negligible compared with an open pit coal mine or a reservoir, and during their operation produce no air pollution. Because of these factors, wind energy is recognized as the world’s fastest-growing new energy source. Small, highly effi cient wind turbines are becoming popular as a source of electricity for rural homes. The cost of installing one comes close to that of putting up poles, overhead power lines and other equipment necessary to connect to the electrical grid. The advantage is that the homeowner owns the generating equipment and is freed from paying monthly electrical bills!


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HelixWind FAQ

How do I get a permit?

Getting a Building Permit

A wind turbine is a structure that requires a building permit. Zoning regulations often limit the height, placement, and other characteristics of "appurtenant" structures, so a conditional (special) use permit or variance may be necessary. It's usually best to let your neighbors know about your installation. Be prepared to answer questions and clear up common misconceptions with well-documented facts about small wind turbines.
" General Starting Information
" Conditional (Special) Use Permits
" Variance
" Letting Your Neighbors Know: Tips for Public Hearings
" Fees
" Useful Links

General Starting Information: Contact County Planning or Permitting Department

Find out what zoning regulations apply to appurtenant, or non-dwelling, structures on your property. Ask if small wind energy systems are specifically addressed by local ordinance, and if so get a copy of the ordinance. You'll need to know the permitting procedures and find out what documentation is required for your turbine. You may have to submit a structural plan drafted by an engineer, but documents from your turbine manufacturer or dealer may be enough. (A checklist of common permitting issues is available for California residents.)

Conditional (Special) Use Permits

If zoning rules list small or residential wind turbines as an approved "conditional" or "special" use for your property, you need only comply with the relevant conditions -- which usually pertain to minimum lot size, maximum tower height, setbacks, and electrical code compliance. The manufacturer or dealer may be able to help with the documentation.
If small wind turbines are not an allowed use, you may have to apply for a conditional use permit, which could involve public hearings before you local planning board.

Check local land-use codes carefully for special zoning ordinances that authorities may have overlooked. A turbine owner in California avoided turbine tower height restrictions through a forgotten wind energy zoning ordinance that had been passed decades earlier.


A zoning variance is a project-specific exception from existing zoning regulations.
If the zoning code prohibits structures more than 35 feet, tall, for example, a wind turbine will probably need a variance from the rule unless special provisions have already been inserted for wind energy systems. Local county or city planning boards usually have to approve variances.

An application for a variance should cite the specific rule and list reasons why a structure should be excepted. Height restrictions are a common barrier for wind turbine applicants, who often find height limits set at 35 feet because fire trucks could not pump water higher than that when the code was written. These rules
are now obsolete, but residents may nevertheless insist on preserving them because they feel taller structures would negatively alter the neighborhood's appearance. You should be prepared to explain that the impact of your wind turbine will be minimal. Take note of other tall structures neighbors
already accept: water towers, rooftop satellite dishes, cellular
communications towers, etc.

Letting Your Neighbors Know...Tips on Public Hearings

BE PREPARED to answer questions about your project, especially if you have to appear at a public hearing seeking a conditional use permit or variance (Conditional or special use permits do not always require hearings, but a variance will). A hearing may turn out to be a mere formality, but be ready for anything that might come up. Here are some tips:
" Seek the support of your neighbors before the hearing.
See AWEA's "Sample Letters"
" Compile documented factual information to reassure anyone worried about noise, visual impact, possible affects on wildlife, and property values.
See AWEA's "Factsheets."
" Planning and zoning officials may be unfamiliar with small wind energy systems, so be prepared to explain the basics. It's helpful to have photographs of similar installations.
See AWEA's "Success Stories."

About Permitting Fees ...

Permitting requirements, procedures, and fees vary widely among counties. Fees for building permits, use permits, zoning permits, and "plot plans" can range from $400 to $1,600. There may be other fees for public notification, hearings, and environmental impact studies costing from a few hundred to several thousand dollars.
Remember, if a fee seems inappropriate or excessive, you may be able to get it reduced or waived. Find out what you are being charged for and offer to provide documentation or information that makes the fee unnecessary.
Some Useful Links
" Permitting Small Wind Turbines: Learning from the California Experience
" Windmills and Zoning Boards site
" AWEA Zoning FAQ
" Small Wind Fact Sheet

Does Helix qualify for a Federal Tax Credit?

Current Status: A handful of states provide some incentives for small wind, but the federal government has not provided any assistance since 1985. The federal Production Tax Credit (PTC) covers only large utility-scale wind projects, not individuals who want to install their own wind power systems for on-site power. In 2005, Congress passed an energy bill that included an investment credit for residential solar energy applications, but did not include small wind systems.
This year, identical bills were introduced in the Senate by Sens. Ken Salazar (D-CO) and Gordon Smith (R-OR) (bill number S. 673), and in the House by Reps. Earl Blumenauer (D-OR) and Tom Cole (R-OK) (bill number H.R. 1772), that would provide $1,500 per ½ kilowatt of capacity for small wind systems. This bills would make the credit available for 5 years for all wind systems 100 kilowatts (kW) of capacity and under, and there would be no cap on the amount of the credit granted per system.

In addition to this tax credit, the bill would provide for:
" Carry-over of credit: In the event that using this credit puts the consumer's taxable income below the minimum threshold, this provision would allow the unusable excess credit to be carried over to the next tax year. This would essentially allow a consumer with a low annual income to take full advantage of the credit.
" Accelerated depreciation of three years.
Current Legislation: S. 673 (Senate) and H.R. 1772 (House). The bills would
create a small wind systems tax credit.
Take Action: Ask Congress to support a small wind systems tax credit. You can help us make a difference. Click on the Legislative Action website to send FREE messages to Congress.
Urge your Senators to cosponsor S. 673, and your Representative to co-sponsor H.R. 1772 to create an investment tax credit for small wind systems.

How does Net Metering work?

Q. What is net metering?

A. "Net-metering" is a simplified method of metering the energy consumed and produced at a home or business that has its own renewable energy generator, such as a small wind turbine. Under net metering excess electricity produced by the wind turbine will spin the existing home or business electricity meter backwards, effectively banking the electricity until it is needed by the customer. This provides the customer with full retail value for all the electricity produced. Without net metering the excess production is sold to the utility at a much lower price. Under existing federal law (PURPA, Section 210) utility customers can use the electricity they generate with a wind turbine to supply their own lights and appliances, offsetting electricity they would otherwise have to purchase from the utility at the retail price. But if the customer produces any excess electricity (beyond what is needed to meet the customer's own needs), the utility purchases that excess electricity at the wholesale or 'avoided cost' price, which is much lower than the retail price. The excess energy is metered using an additional meter that must be installed at the customer's expense. Net metering simplifies this arrangement by allowing the customer to use any excess electricity to offset electricity used at other times during the billing period. In other words, the customer is billed only for the net energy consumed during the billing period.

Q. Why is net metering important?

A. There are three reasons net metering is important. First, because wind energy is an intermittent resource, customers may not be using power as it is being generated, and net metering allows them to receive full value for the electricity they produce without installing expensive battery storage systems. This is important because it directly affects the economics and pay-back period for the investment. Second, net-metering reduces the installation costs for the customer by eliminating the need for a second energy meter. Third, net metering provides a simple, inexpensive, and easily-administered mechanism for encouraging the use of small-scale wind energy systems, which provide important local, national, and global benefits to the environment and the economy.

Q. What are the benefits and costs of net metering?

A. Net metering provides a variety of benefits for both utilities and consumers. Utilities benefit by avoiding the administrative and accounting costs of metering and purchasing the small amounts of excess electricity produced by small-scale wind energy facilities. Consumers benefit by getting greater value for some of the electricity they generate and by being able to interconnect with the utility using their existing meter. The only cost associated with net metering is indirect: the customer is buying less electricity from the utility, which means the utility is collecting less revenue from the customer. That's because any excess electricity that would have been sold to the utility at the wholesale or 'avoided cost' price is instead being used to offset electricity the customer would have purchased at the retail price. In most cases, the revenue loss is comparable to having the customer reducing electricity use by investing in energy efficiency measures, such as compact fluorescent lighting, efficient heating and cooling equipment, or other highly-efficient appliances.

The bill savings for the customer (and corresponding revenue loss to the utility) will depend on a variety of factors, particularly the difference between the 'avoided cost' and retail prices and the amount of excess electricity produced. In general, however, the difference will be between $10-40 a month for a 10 kilowatt residential wind energy system. Moreover, any utility revenue losses associated with net metering are at least partially offset by administrative and accounting savings, which are not included in the above figures. These savings can exceed $25 a month because, absent net metering, utilities have to separately process the accounts of customers with wind turbines and issue the monthly checks. In practice, these checks can be for as little as 5 cents.

Q. Can I really use my existing meter to take advantage of net metering?

A. The standard kilowatt-hour meter used for most residential and small commercial customers accurately registers the flow of electricity in either direction. This means the 'netting' process associated with net metering happens automatically - the meter spins forward (in the normal direction) when the customer needs more electricity than is being produced, and spins backward when the customer is producing more electricity than is needed in the home or building. The meter registers the net amount of energy produced or consumed during the billing period.

Q. What is the current status of net metering?

A. Currently, 28 states require at least some utilities to offer net metering for small wind systems, althoughthe requirements vary from state to state. Most state net metering rules were enacted by state utility regulators, and these rules apply only to utilities whose rates and services are regulated at the state level. In recent years many states have enacted net metering laws legislatively, including California, Connecticut, Massachusetts, Montana, Nevada, New Hampshire, New Jersey, Oregon, Vermont, Virginia, and Washington.
In most of the states with net metering statutes, all utilities are required to offer net metering for small wind systems. To find out whether net metering is available in your location, contact the American Wind Energy Association at the address below, or go to the policy area of the AWEA web site, <> and follow the links regarding net metering.
source: Kathy Belyeu, American Wind Energy Association, (202) 383-2504,

How much does electricity cost?

The cost of electricity depends on where you live, how much you use, and possibly when you use it. There are also fixed charges that you pay every month no matter how much electricity you use. For example, I pay $6/mo. for the privilege of being a customer of the electric company, no matter how much energy I use.
Check your utility bill for the rates in your area. If it's not on your bill then look it up on the utility's website.

The electric company measures how much electricity you use in kilowatt-hours, abbreviated kWh. Your bill might have multiple charges per kWh (e.g., one for the "base rate", another for "fuel") and you have to add them all up to get the total cost per kWh.
Most utility companies charge a higher rate when you use more than a certain amount of energy, and they also charge more during summer months when electric use is higher. As an example, here are the residential electric rates for Austin, Texas (as of 11-03):

First 500 kilowatts 5.8¢ per kilowatt hour (kWh)
Additional kilowatts (May-Oct.) 10¢ per kilowatt hour
Additonal kilowatts (Nov.-Apr.) 8.3¢ per kilowatt hour
These figures include a fuel charge of 2.265¢ per kWh.
The average cost of residential electricity was 9.86¢/kWh in the U.S. in March 2006. The average household used 888 kWh/mo. in 2001 and would pay $87.56 for it based on the March 2006 average rate. (Dept. of Energy)
The cost of electricity varies by region. In 2003 the price ranged from 5.81¢ in Tennessee to 12¢ in California, 14.314¢ in New York, and 16.734¢ in Hawaii. In Summer 2001, electricity was a whopping 20¢/kWh in parts of California.
Source: Michael Bluejay

What is kilowatt hour?

The rate of electrical use at any moment is measured in watts. For example:
" A 100-watt light bulb uses 100 watts.
" A typical desktop computer uses 65 watts.
" A central air conditioner uses about 3500 watts.
If your device lists amps instead of watts, then just multiply the amps times the voltage to get the watts. For example:
2.5 amps x 120 volts = 300 watts

To know how much energy you're using you have to consider how long you run your appliances. When you run a 1-watt appliance for an hour, that's a watt-hour. It's abbreviated Wh. For example:
" One 100-watt light bulb on for an hour is 100 watt-hours (100 Wh)
" One 100-watt light bulb on for five hours is 500 Wh
" Five 100-watt light bulbs on for an hour is 500 Wh

1,000 watt-hours is a kilowatt-hour (kWh). For example.
" One 100-watt light bulb on for an hour, is 0.1 kWh (100/1000)
" One 100-watt light bulb on for ten hours is 1 kWh (1 bulbs x 100W x 10h= 1000Wh = 1 kWh)
" Ten 100-watt light bulbs on for an hour, is 1 kWh (10 bulbs x 100W x 1h= 1000Wh = 1 kWh)
" Ten 50-watt light bulbs on for an hour, is 0.5 kWh
" Ten 100-watt light bulbs on for 1/2 an hour, is 0.5 kWh
" Running a 3500-watt air conditioner for an hour is 3.5 kWh.

Take a moment to understand the difference between kilowatts and kilowatt-hours. The former is the rate of power at any instant. The latter is the amount of energy used A light bulb doesn't use 60 watts in an hour, it uses 60 watt-hours in an hour.
The "-hours" part is important. Without it we'd have no idea what period of time we were talking about. If you ever see a reference without the amount of time specified, it's almost certainly per hour.

Vertical versus Horizontal Turbines

Advantages of vertical wind turbines

" Easier to maintain because most of their moving parts are located near the ground. This is due to the vertical wind turbine's shape. The airfoils or rotor blades are connected by arms to a shaft that sits on a bearing and drives a generator below, usually by first connecting to a gearbox.
" As the rotor blades are vertical, a yaw device is not needed, reducing the need for this bearing and its cost.
" Vertical wind turbines have a higher airfoil pitch angle, giving improved aerodynamics while decreasing drag at low and high pressures.
" Mesas, hilltops, ridgelines and passes can have higher and more powerful winds near the ground than up high because of the speed up effect of winds moving up a slope or funneling into a pass combining with the winds moving directly into the site. In these places, VAWTs placed close to the ground can produce more power than HAWTs placed higher up.
" Low height useful where laws do not permit structures to be placed high.
" Smaller VAWTs can be much easier to transport and install.
" May not need a free standing tower so is much less expensive and stronger in high winds that are close to the ground.
" Usually have a lower Tip-Speed ratio so less likely to break in high winds

Disadvantages of vertical wind turbines

" Most VAWTs produce energy at only 50% of the efficiency of HAWTs in large part because of the additional drag that they have as their blades rotate into the wind. This can be overcome by using structures to funnel more and align the wind into the rotor (e.g. "stators") or the "vortex" effect of placing straight bladed VAWTs closely together.
" There may be a height limitation to how tall a vertical wind turbine can be built and how much sweep area it can have.
" A VAWT that uses guyed wires to hold it in place puts stress on the bottom bearing as all the weight of the rotor is on the bearing. Guyed wires attached to the top bearing increase downward thrust in wind gusts. Solving this problem requires a superstructure to hold a top bearing in place to eliminate the downward thrusts of gust events in guyed wired models.

Advantages of horizontal wind turbines

" Blades are to the side of the turbine's center of gravity, helping stability.
" Ability to wing warp, which gives the turbine blades the best angle of attack. Allowing the angle of attack to be remotely adjusted gives greater control, so the turbine collects the maximum amount of wind energy for the time of day and season.
" Ability to pitch the rotor blades in a storm, to minimize damage.
" Tall tower allows access to stronger wind in sites with wind shear. In some wind shear sites, every ten meters up, the wind speed can increase by 20% and the power output by 34%.
" Can be sited in forests above the treeline.
" May be self-starting.

Disadvantages of horizontal wind turbines

" HAWTs have difficulty operating in near ground, turbulent winds because their yaw and blade bearing need smoother, more laminar wind flows.
" The tall towers and long blades (up to 180 feet long) are difficult to transport on the sea and on land. Transportation can now cost 20% of equipment costs.
" Tall HAWTs are difficult to install, needing very tall and expensive cranes and skilled operators.
" Supply of HAWTs is less than demand and between 2004 and 2006, turbine prices increased up to 60%. At the end of 2006, all major manufacturers were booked up with orders through 2008.
" The FAA has raised concerns about tall HAWTs effects on radar in proximity to air force bases.
" Their height can create local opposition based on impacts to viewsheds.
" Offshore towers can be a navigation problem and must be installed in shallow seas. HAWTs can't be floated on barges.
" Downwind variants suffer from fatigue and structural failure caused by turbulence.

What are the dimensions?

Helix wind turbines currently come in two sizes, the Helix 1 kw home for residential applications, which stands 9' feet tall by 4' feet in diameter (2.74m x 1.21m). The commercial turbine, the Helix 2 kw measures 12' feet in height by 4' feet in diameter, (3.6m x 1.21m).

How tall is the mounting pole?

The overall height includes the mounting pole and turbine. The poles come in 5 foot increments which attach together plus 9 feet for the 1 kw turbine and generator. Pole length is determined by local zoning regulations and site characteristics.

What are rotor startup/shutdown speeds?

The low speed Helix Wind turbine will start generating power at a little over 1 m/s (3.5 mph). It is self-starting and requires no power or input to spin up. It does not need over speed control because of its design and will continue to output power as wind increases up to 35mph. The unit will continue to spin with no damage to the system in winds as high as 80 mph (this is a sustained speed, it can withstand gusts up to 125 mph), however no additional electricity will be generated above maximum output at 35 mph due to restrictions on the inverter.

Is it safe for Birds and Bats?

Helix Wind turbines are completely safe for wildlife because they spin at much lower speeds than horizontal turbines and appear as a solid mass rather than a sharp blurring blade that a bird or bat cannot see or detect.

Does the turbine make noise?

The Helix Wind turbines are nearly silent because they operate with tip speeds close to the wind velocity. This dynamic is similar to the wind blowing around any stationary object such as a tree or house. Conventional (horizontal) wind turbines spin at up to 10 times the wind speed which causes the whistling sound that can be heard around them.

What are the mass & loadings?

The Savonious 1.8 weighs approximately 250lb not including the pole structure. Each 5 feet of tower pole weighs approximately 140 lbs.

How close can these turbines be mounted to each other?

The distance between turbines depends on each individual site. Some locations with strong, consistent prevailing winds can have adjacent turbines 6 feet apart. Other settings might require them to be 30 feet apart to minimize shadowing and a reduction in power output. The optimal layout places consecutive turbines in a line perpendicular to the prevailing wind.

Can I sell electricity to the grid ?

The laws/regulations vary quite a bit between jurisdictions, and there is a physics component to be careful of. There is a concept called "net metering" where customers connected to the Distribution system (as opposed to High Voltage customers) can net off the electricity they produce but not below zero. In other words, customers cannot actually sell surplus to the grid from home generation. The regulations that require electric utilities to buy tend to apply to customers directly connected to the high voltage. Most radial systems (i.e., distribution grids) are not designed to have injections of power at the lowest transformer levels. If the surplus power cannot be taken up by the other homes / businesses connected to the same transformer, then the transformer has to be replaced with a two way one, in order to step up power back to the voltage that runs inter-transformer. So there is a physics reason for this prohibition, not just utility policy.

What safety features are there?

The Helix Wind is constructed of high strength aluminum and stainless steel for a lifetime of use in extreme environments. The interlocking blade structure provides redundant load paths making a highly damage tolerant unit. The unit has an emergency brake for user initiated shutdown. Under normal expected conditions there is no need to stop the turbine, it will safely operate in 55 mph winds.

Does it have accreditation?

The Grid-Tie Inverter has CE marking and is currently undergoing evaluation for UL and cUL listing. The turbine and generator assembly is currently be tested for UL listing. With UL listing the Helix Wind is eligible for rebates under all state Renewable Energy Programs.

How do I calculate my Helix investment payback ?

Unfortunately, accurately calculating the payback on your wind turbine investment is not as simple as it might seem. Wind turbine performance depends on a variety of factors including wind speed, tower height, wind shear, turbulence, local tree and building placement and air density. We're happy to perform a custom analysis and estimate of the payback on your investment, just click here to simply fill out the fields and one of our Performance Analysts will contact you with your results.

What are the economics of Small Wind?

Although small wind systems involve a significant initial investment, they can be competitive with conventional energy sources when you account for a lifetime of reduced or altogether avoided utility costs, especially considering escalating fuel costs.

The cost of buying and installing a small wind energy system typically ranges from about $3,000-5,000 per kilowatt for a grid-connected installation, less than half the cost of a similar solar electric system. The length of the payback period (or, the time it takes to "break even") depends on the system you choose, the wind resource at your site, your power provider's electricity rates, and financing and incentives available. Small wind owners with strong average wind speeds who can take advantage of rebate programs can usually recoup their investments within fifteen years.

Many states have rebate or tax credit programs in place to encourage small wind and other renewable energy applications. AWEA's state-by-state1 pages provide information specific to buying and installing a small wind turbine in each of several U.S. states, including the availability of net metering2, local or state incentive programs, and utility incentives.

The cost of a wind system has two components: initial installation costs and operating expenses. Installation costs include the purchase price of the complete system (including tower, wiring, utility interconnection or battery storage equipment, power conditioning unit, etc.) plus delivery and permitting costs, installation charges, professional fees and taxes.

A Good Investment for Windy Landowners with High Bills

A 10-kW grid-connected residential-scale system generally costs $35-40,000 to install. The best candidates for these systems are rural homes and businesses with at least an acre of property, a Class 2 or better wind resource3, and utility bills averaging $150 per month or more. If a net metering arrangement4 is available from the utility, most of the power generated by a grid-connected system can be valued at the retail rate of electricity, reducing the amount of time it takes for a system to pay for itself.

In California, where net metering and the nation's highest electric rates are combined with a substantial rebate program and a state tax credit, small wind system owners with strong wind resources can recoup their initial investment in under 10 years, and enjoy essentially free electricity for the remainder of the system's 30-year useful life. Such a wind energy system can be an excellent, low-risk investment. It can provide a return of up to 15-20%, depending on electric usage and the wind resource.

Smaller Systems Can Offset Electricity Costs, Provide Independence
Smaller wind energy systems also can be used to offset electricity costs, or to independently power specific applications such as water pumps or recreational vehicle lights and appliances.

A 3 kW turbine, including 60-80 foot tower, utility-tie inverter, batteries for back-up system, utility switch box, battery system box, hardware and installation components, costs about $15,000. A homeowner using $60-100 per month of electricity can save 10-20% off the electric bill with a 1 kW turbine, given strong wind resources. The same homeowner could expect to save 30-60% off that electric bill using a 3 kW turbine. (Savings depend on average annual wind speed, tower height, electrical cost and average electric bill.)

Systems smaller than 1 kW are more typically used in stand-alone applications, or as part of a hybrid system with solar PV cells. A 400-watt system can be installed for $1,500.

Remote systems may require operating battery storage. Individual batteries cost from $150 to $300 for a heavy-duty, 12 volt, 220 amp-hour, deep-cycle type. Larger capacity batteries, those with higher amp-hour ratings, cost more. A 110-volt, 220 amp-hour battery storage system, which includes a charge controller, costs at least $2,000.

Off-Grid Systems Can Be the Least-Cost Option for Electricity
The cost of extending the utility grid to a new home location can be significant, sometimes as high as $20,000-$30,000 for a distance of only one-quarter of a mile. For the same initial investment, a utility-independent renewable energy system can be installed that will meet the electricity needs of an energy-efficient home. Such a system will typically include a combination of a wind turbine, photovoltaics, batteries, an inverter, and a back-up generator. These systems can be cost-effective on a first-cost basis alone, not to mention the avoidance of monthly utility bills for years to come.

The Electric Power Research Institute has gone so far as to suggest that in some cases it may make more economic sense to remove under-used transmission lines in the United States and serve the loads with hybrid stand-alone power systems rather than continuing line maintenance. More information on the economics of small wind systems can be found in the U.S. Department of Energy's Consumer Guide to Renewable Energy for Your Home or Energy5 and the Iowa Energy Center's Wind Energy Manual.6See AWEA's online Small Wind Toolbox7 for descriptions and links to numerous financial incentives including:

Investment Tax Credits
Investment Incentives (grants/rebates)
Revolving Loan Funds
Sales Tax Reductions
Property Tax Reductions

Other Fact Sheets Available on Small Wind Energy
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