Frequently Asked Questions
What do wind turbines look like?
There are two basic types of wind turbines: horizontal axis and vertical axis, or "egg beater" style. Horizontal-axis wind turbines are by far the most common, representing more than 95 percent of all utility-scale turbines (i.e., capacity of 100 or more kilowatts). From the top of the swept area to the ground, a large, commercial horizontal-axis wind turbine can be about 80 metres tall.
How reliable is wind energy?
Sophisticated monitoring and wind resource analysis allow wind developers to estimate with a high degree of certainty "when" and "how much" wind energy is available, so system planners can forecast wind power deliveries. When the wind blows, it can displace fossil-fueled generation such as oil and gas. Studies have shown that when a utility diversifies its power portfolio with the addition of wind energy, it can meet demands more reliably.
What happens when the wind doesn't blow?
When the wind is calm, the turbine is at rest. However, at the hub height of a utility-scale wind turbine – usually about 80 metres above ground – on a site selected specifically for its good wind resources, it is rare for the wind to be totally still.
What does the computer system inside a wind turbine do?
The elaborate computer system inside a turbine performs thorough self-diagnostic tests and troubleshoots errors before the startup command is given. If the computer detects any problems it cannot auto-correct, the turbine automatically shuts down. In addition, a SCADA (system control and data acquisition) control system allows a remote operator (using a modem from anywhere in the country) to set new operating parameters, perform system checks and ensure turbines are operating at peak performance.
Is wind energy just the latest energy fad?
Not at all. Today, wind energy is the fastest-growing renewable energy resource in the world. Wind energy has always been clean and renewable and, over the past 20 years, the cost of wind energy has dropped about 80 percent.
How safe are wind turbines?
Wind energy is one of the safest energy technologies, with several built-in safety features.
"They also require minimal maintenance, and the reliability of wind turbines, measured in terms of availability to make electricity when the wind is blowing, is better than 98 percent." (Source: Paul Gipe, Wind Power Comes of Age, 1996)
Are wind turbines noisy?
Wind turbines have moving parts, but the sound they make is virtually undetectable from a distance. You would have little difficulty conversing right beneath one.
NextEra Energy Canada takes two primary steps to assure minimal sound impact on neighbours. First, wind turbine manufacturers guarantee that turbine sound levels will fall below set sound level restrictions, minimizing sound reaching adjacent homes. Second, sound from a wind turbine diminishes over distance, so in Ontario for instance, we are careful to meet or exceed the 550 metre separation distance between wind turbines and homes. The Ontario Ministry of Environment's Sound Guidelines for rural areas establish maximum permissible sound levels at residences of 40 decibels, which is consistent with the standards set by the United States Environmental Protection Agency.
Should we be concerned about living close to turbines?
NextEra Energy Resources takes concerns about human health very seriously. Although much has been written about health effects associated with wind turbines, we have found no credible, scientifically peer-reviewed study that demonstrates a link between wind turbines and negative health effects. On the contrary, the study "Wind Turbine Sound and Health Effects: An Expert Panel Review" had the following key conclusions:
- Sound from wind turbines does not pose a risk of hearing loss or any other adverse health effect in humans.
- Subaudible, low frequency sound and infrasound from wind turbines do not present a risk to human health.
- Some people may be annoyed at the presence of sound from wind turbines. Annoyance is not a pathological entity.
- A major cause of concern about wind turbine sound is its fluctuating nature. Some may find this sound annoying, a reaction that depends primarily on personal characteristics as opposed to the intensity of the sound level.
The full report can be found in the Canadian Wind Energy Association's website, www.canwea.ca/pdf/talkwind/Wind_Turbine_Sound_and_Health_Effects.pdf.
In a recent decision on the Kent Breeze Wind project in Chatham-Kent, Ontario the Ontario Ministry of Environment states:
'The Chief Medical Officer of Health agreed to undertake a review of existing information and to consult with the Ontario Agency for Health Protection and Promotion and local medical officers of health on health effects related to wind turbines. The results of the review and consultation were published on May 20, 2010 and released in a report titled "The Potential Health Impacts of Wind Turbines." The review concluded that scientific evidence available to date does not demonstrate a direct causal link between wind turbine noise and adverse health effects. The sound level from wind turbines at common residential setbacks is not sufficient to cause hearing impairment or other direct health effects, and there is no scientific evidence to date that vibration from low frequency wind turbine noise causes adverse health effects.
Regarding shadow flicker, a common concern is its possible relationship to epilepsy. The Chatham-Kent Board of Health reviewed potential impacts in their report dated June 2008 and stated that 'The frequency of wind turbines is well below the current known documented threshold for triggering epilepsy symptoms.'
Additionally, the Province of Ontario has appointed Dr. Siva Sivoththaman at the University of Waterloo as the Ontario Research Chair in Renewable Energy Technologies and Health. This position is dedicated to "actively monitoring and providing the latest in scientific research and data about any possible health impacts of renewable energy."
NextEra Energy Canada's projects have been designed to meet or exceed all the regulations prescribed by the Ministry of Environment. NextEra Energy Canada will have a communication program in place to address any concerns related to the operation of the project, should they arise.
Will the turbines affect agriculture and/or livestock?
Wind turbines occupy only a small fraction of the land they are sited on and work in harmony with its established uses. Farming and grazing continue undisturbed. In general, a turbine in a typical wind farm including foundation and access roads will use 1.0 – 1.5% of a typical 40 hectare farm parcel.
NextEra Energy Resources operates over 85 wind farms amidst a variety of agricultural uses and livestock operations. It has not been the experience of NextEra Energy Resources that wind turbine operations have any negative impact on livestock or crops. Quite the opposite in fact, many landowners find that the guaranteed income from hosting a wind turbine helps to stabilize the economics of their operations.
Will the turbines affect local wildlife?
When properly sited, wind turbines present less of a danger to birds than other structures such as buildings or roads. The location of turbines, as well as numerous other decisions associated with developing our wind farms, are carefully designed to minimize these effects. As part Ontario's REA process, NextEra Energy Canada is working with experts to assess the potential effects on local wildlife, including birds and bats.
Our work plans and results are reviewed by Environment Canada, the Canadian Wildlife Service and the Ontario Ministry of Natural Resources as part of the approval of our REA application.
How does the cost of wind energy compare to other energy sources?
The cost of wind power generation is competitive with that of many other newly-installed power sources. Once turbines are installed, the cost of generating wind power will remain steady for decades – the fuel (wind) is free. By contrast, electricity prices have risen steadily across Canada over time. Potential regulations to make polluters pay for their emissions will mean that the cost of power from fossil fuels will continue to rise, on top of normal market fluctuations. Under the terms of our contract with the Ontario Power Authority, any economic benefits from future pollution regulation will flow to them.
Comparing the cost of new generation, such as wind, to the cost of power from existing and legacy generation, such as coal and hydro, is an unfair comparison. The comparison should be between the cost of different types of generation if they were to be built today. The majority of Ontario's current energy mix and resulting spot price is a result of old assets, whose capital costs were financed and accounted for years ago. Therefore, their operating costs are much lower. Additionally, power prices in Ontario are still heavily regulated and do not reflect the true cost of power in the market.
The Government of Ontario's Long Term Energy Plan is to displace coal-fired generation with renewable energy. Other forms of electricity have hidden costs related to health. A 2005 study prepared for the government found that the average annual health-related damages due to coal could top $3 billion.
Will the wind farm impact future economic development in the area?
We have universally found that our wind farms have a positive impact on the future economic development of an area, increasing the economic base of the community through additional tax revenue, new construction jobs and full-time permanent jobs once the plant is operational. Income to local businesses, including motels, caterers, office supply companies, construction firms, rental companies and others, also add to the economic development of the local area. Furthermore, wind farms increase the economic return on agricultural operations in the area, preserving traditional land use.
What involvement does the community have in a wind energy project?
Building a strong partnership with the community is critical to the success of every one of our projects. With community dialogue a vital component of our strategy, we start speaking with residents early in the project development process to introduce the project and solicit early feedback on our proposal. Our goals are to:
- Establish a cooperative relationship with the community
- Listen to our neighbors
- Share information
- Ensure that our proposal fits the interests and priorities of the community
We also meet with elected and appointed officials, civic associations, environmental groups and other community organizations. We periodically share new information, as it becomes available, to provide project updates to the community.
Should I be concerned about the value to my property?
There is no evidence to show a decline in property values from the siting of a wind farm.
Excerpt from the Chatham-Kent property value study 2010:
"In the study area, where wind farms were clearly visible, there was no empirical evidence to indicate that rural residential properties realized lower sale prices than similar residential properties within the same area that were outside of the viewshed of a wind turbine. No statistical inference to demonstrate that wind farms negatively affect rural residential market values in Chatham-Kent was apparent in this analysis."
Excerpt from the Berkeley Lab property value study 2009:
"Specifically, neither the view of the wind facilities nor the distance of the home to those facilities is found to have any consistent, measurable, and statistically significant effect on home sale prices. Wind facilities have had no widespread and statistically identifiable impact on residential property values."
How much land does a wind farm require?
A wind farm in open, flat terrain generally requires about 40 acres per megawatt of installed capacity. As little as 1 percent of that total acreage is needed for turbines and access roads, meaning as much as 99 percent remains free for other uses, such as farming or ranching. A wind plant on a ridgeline in hilly terrain will require much less space – as little as two acres per megawatt.
How much income can a wind turbine generate for a landowner?
Commercial terms and lease agreements can vary widely, based on a number of factors, such as the:
- Available wind resources
- Accessibility to transmission lines
- Per kilowatt price that utility customers are willing to pay for wind power
Providing leases on small portions of the overall acreage for siting wind turbines can subsidize poor crop conditions and help landowners hold on to family farms and ranches.
What does a lease cover?
The easement will most likely cover:
- Payment terms
- Length of lease
- Other uses of the property
- The location and type of access roads and other support facilities
- The condition of the land after wind operations cease
What impact does a wind farm have on surrounding land?
Once a wind farm is operational, there should be virtually no disruption to the surrounding land. Wind turbines and access roads (which are constructed along property lines whenever possible so as not to disrupt access to crops and stock) usually account for approximately 1 percent of overall acreage. Farm animals can graze immediately below a wind turbine, because even at the bottom of its swing, the rotor blade is generally more than 100 feet above the ground.
Is construction planned around harvest / planting seasons?
No. However, landowners are compensated for loss of crops during construction and loss of yield in future years due to soil compaction from construction equipment. Determining when construction begins depends more upon the completion of lease agreements and permitting, as well as having the wind farm operational before peak wind seasons arrive, which varies by region.
Is there construction traffic?
Yes. During construction there will be additional traffic, although the construction of wind turbines is relatively quick when compared to other types of power plants. Some can be brought online in a matter of months, versus natural gas power plants, for example, which can take two years or more to build.
Although construction is temporary, it will require heavy equipment, including bulldozers, graders, trenching machines, concrete trucks, flatbed trucks and large cranes.
The process involves:
- Land clearing, grading, laying out access roads, turbine sites and cable routes
- Excavating and pouring concrete foundations
- Digging trenches for underground electrical cables
- Laying electrical and communication cables
- Building overhead collection system, substation and transmission lines to the utility system (if required)
- Assembling and erecting wind turbine towers
- Mounting nacelles on top of towers
- Attaching rotors
- Making electrical connections between towers and the power collection system
- Testing the system
What is the shadowing effect?
A wind turbine, like almost any other tall structure, will cast a shadow when the sun is shining. The rotor blades may chop the sunlight, causing a flickering or blinking effect while the rotor is in motion. Because shadow flicker is diffuse and limited to predictable, brief time periods just before sundown or after sunup, it is an aesthetic rather than a safety issue. Yet, because some residents are still concerned, if NextEra Energy Canada receives a verified complaint about shadow flicker at any home involved in the project, we at NextEra Energy Canada are committed to utilizing the best source to mitigate the problem, including but not limited to, planting trees in the line of sight or by installing window treatments or awnings.
What happens when wind turbines are removed?
The siting of wind turbines is governed by long-term agreements that can cover periods of up to 20 to 30 years, depending upon the expected life span of the turbine. When turbines are removed, the land is returned to virtually its original condition. Typically, tower foundations and other structures are removed to a specified below-ground depth.
Is an environmental review performed?
An environmental review is performed for every project. NextEra Energy Canada works to preserve cultural and environmental resources. Wind projects are sited in areas where there is good wind, the ability to transmit the energy, a market for the energy, and land use is compatible with a wind farm.
What is involved in the permitting process in Ontario?
The Green Energy Act in Ontario requires renewable energy projects to undertake a Renewable Energy Approval (REA) process. Under this approval process, we are assessing whether our proposed projects will have impacts on cultural and heritage resources and the natural environment (e.g. significant habitat, areas of natural scientific interest).
The Ontario Ministry of Natural Resources (MNR) and the Ontario Ministry of the Environment (MOE) will review the results of our impact assessment when we submit our REA application. The flow-chart provides an overview of the approval process and highlights formal opportunities for public input throughout the process. We welcome feedback and questions about our projects at any time.
If potential impacts are found, we will determine how changes to our design can reduce, eliminate or mitigate the potential effects. Setbacks (the distance between a proposed turbine location and a specific feature) have been established under the Green Energy Act for people's homes, roads, wetlands, watercourses, woodlots, parks and conservation areas, and a variety of other landscape features. These setbacks ensure that wind projects take into account the well-being of people and the natural environment. It is our responsibility during the REA process to ensure that we have a complete understanding of the local environment and of the human landscape – the locations of homes, businesses, schools and heritage resources. Throughout the REA process, we will communicate and consult with the communities near our proposed projects to ensure we hear their comments and address any concerns or questions.
How long does the entire development process take, i.e., from submitting permits to producing electricity?
The length of time will vary from project to project, but wind farms can be brought on-stream faster than most other types of power-generating facilities. For example, natural gas power plants can take two to three years or more to develop. The permitting process for wind is less complex because wind energy does not have the same environmental impact as fossil-fueled power generators. Wind energy produces no emissions and no solid waste by-products. The length of construction will depend primarily upon the number of turbines to be erected, the terrain and prevailing weather conditions. In some cases, this can all be accomplished within six to nine months.
What affect do wind turbines have on the transmission grid?
Wind turbines can provide a unity power factor and help in stabilizing voltage. Newer wind generators have switched capacitors that are applied as generation and VAR demand increases, keeping power factor above 99 percent. One turbine now on the market uses power electronics and a variable speed rotor to automatically maintain the desired grid voltage or reactive power flow to the utility. This design feature is particularly beneficial to weaker grids.
How difficult is it to integrate wind turbines with utilities?
A study of system interface and operational issues by Robert Putnam of Electrotek Concepts found no insurmountable challenges. He noted, "Any issues that have developed, such as intermittency and voltage regulation, can be addressed by accepted power system procedures and practices." (Source: American Wind Energy Association in Wind Energy Weekly, #680, 15 January 1996)