Jeremy Stanford
St:# 20486337
ME 765
October 16, 2018
University of Waterloo
Department of Mechanical and Mechatronics Engineering
Feasibility of Small, Home-Scale
Wind Energy Generation
ME 765
Date: December 6, 2018
Prepared for:
Prof. David Johnson
Department of Mechanical and Mechatronics Engineering
University of Waterloo
Prepared by:
Jeremy Stanford 20486337
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Abstract
The purpose of this report is to act as a guide for those interested in the small, home-scale
wind energy generation systems. Explaining the advantages of renewable energy and how to
implement a successful system renewable energy system, as well as discussing the feasibility of
installing a small wind energy system, in order to determine their worth while from both an energy
and economic standpoint. The importance of wind power and other renewable forms of energy will
first be discussed in relation to the current environmental climate, before delving into the details of
how wind energy generation works and how to determine if is suitable for a proposed location.
How to determine the sizing of the system needed as well as the different type of energy systems
(off-grid and grid-tied) their components, uses and specific considerations are then discussed to
help develop a broader understanding of the options available in order to pick the system which
works best for the proposed location. The drawbacks of wind energy generation and main
challenges to the implementation of a successful wind energy system are then discussed before
finally providing recommendations as to how to get the most out of proposed wind energy system,
and what other forms of renewable energy may also be beneficial to consider.
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Table of Contents
Abstract ..................................................................................................................................... Pg. 2
Why Is Wind Power Important? ................................................................................................ Pg. 4
Harnessing the Power of the Wind ............................................................................................ Pg. 5
Determining if Your Property is Suitable.................................................................................. Pg. 6
Sizing Your Turbine .................................................................................................................. Pg. 9
Going Off the Grid .................................................................................................................... Pg. 9
Energy Storage ........................................................................................................................ Pg. 11
Grid Integration ....................................................................................................................... Pg. 12
Economics ............................................................................................................................... Pg. 13
Main Challenges/Drawbacks of Wind Energy ........................................................................ Pg. 16
Conclusion ............................................................................................................................... Pg. 17
References ............................................................................................................................... Pg. 20
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Why Is Wind Power Important?
Arguably the biggest problem facing the world today is climate change. In fact, recent
projections by the United Nation Framework Convention on Climate Change (UNFCCC) suggest
that “average temperatures could increase by another 1.4 to 5.8 °C by 2100“ [1]. A global effort is
in place to try and keep temperatures down, and a 1.5°C increase limit has been placed alongside
legally binding goals to hold global temperatures “well below” the 2°C above pre-industrial levels
danger zone, in the Paris Agreement [1]. However recent research indicates that the opportunity to
remain within these targets have already passed. According to a report released by the Food and
Agriculture Organization (FAO), “Assuming a maximum GHG emission reduction rate of 5
percent per year, the 1.5 °C target is probably already unachievable and the 2 °C target will also be
missed if no action is taken prior to 2027” [2]. The first area to focus on in order to minimize the
drastic climate changes we are going through is energy use and more specifically, our sources of
energy. Although it is evident from statistics that much of the developed world uses and abuses the
seemingly endless supply of energy available on a daily basis, these abuses of energy would not be
as substantially bad if they were derived from cleaner sources than fossil fuels. The combustion of
fossil fuels release harmful chemicals and toxins into the environment as well as an abundance of
greenhouse gases such as carbon dioxide, which is seen as one of the main contributors to climate
change. By reducing dependence on fossil fuels and switching the focus to more sustainable
renewable energy sources, the harmful effects of climate change can help be minimized. Wind
power can help to reach these renewable energy goals and combat the harsh effects of climate
change in a number of ways; it is “environmentally friendly”, it “causes absolutely no pollution”
(to the environment), and aside from the initial installation and occasional maintenance costs,
provides an “essentially free” source of power that will ever cease to exist [3]. As a result,
homeowners who properly take advantage of the wind resources available to them can “have a
ready supply of wind-generated electricity for decades” [3]. A small, properly placed turbine in a
small wind electric system can “significantly lower home electricity bills” [3, small wind], “help
avoid the high costs of having utility power lines extended to a remote location” [4], “help
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uninterruptible power supplies ride through extended utility outages” [4], and can also be used for
various other applications, such as pumping water; similar to setups that have been used on farms
and ranches for decades.
Additionally, with the technology “developing quickly”, and “clean energy and special
financing options” available depending on the state/province of residence, wind power is becoming
more practical and accessible to the average homeowner. [3]
Harnessing the Power of the Wind
Wind is an abundant energy resource available worldwide that results from the “unequal
heating of the Earth's surface by the sun” [4]. As a result, wind is an inexhaustible resource that is
capable of supplying energy as long as the sun exists. In order to capture this energy in a form that
can be utilized for work. This is typically accomplished through the use of permanent magnet
alternators coupled directly to the rotor blades, so that when the wind spins the rotor, the turbine
converts the kinetic energy of the wind into a rotary motion. This motion in turn drives the
generator, transmitting electricity down the tower via wires, (typically in the form of three-phase
alternating current) and producing “clean energy” [5, 4]. These wind turbines will continue to
generate electricity “as long as there is relatively constant wind at a reasonable speed” [6]. This
speed is referred to as the turbine’s “Cut-in Wind Speed” and usually falls around the speed of 3.5
- 4.5 m/s [6].
Because the wind speed typically increases with an increase in height, in order to obtain the
most power possible at a given location, small scale wind turbines are typically mounted on top of
tall towers in order to expose them to “more consistent wind with a higher average speed” [6].
Additionally, although wind turbines need fairly high speeds in order to produce the power at all,
they also require not just fast wind, but “nicely flowing, smooth, laminar” wind flows, which
“cannot be found at 30 feet height”; as wind that is close to the ground “is turbulent, and makes a
poor fuel for a small wind turbine” [7]. Consequently, these towers also help to situate the turbine
at a height in which the wind is not being effected by obstacles on the ground such as trees and
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buildings, and can therefore extract the maximum, high-quality power output that the wind can
provide.
There are two basic types of towers
utilized for wind turbines. The self-supporting
(free-standing) tower, which provides the
benefit of minimum ground area
requirements, but are far more expensive and
difficult to install. And the guyed tower,
whose low cost and ease of installation make
it the more common choice for home wind
power systems, provide some additional
difficulties when choosing the right location
for the turbine as they require a guy radius at
Figure 1: Tower Height vs. Power [7]
least ½ to ¾ of the tower height, significantly
increasing the ground area used for each turbine [4]. Guyed towers are also available in tilt-down
versions, that are more expensive, but “offer the consumer an easy way to perform maintenance on
smaller light-weight turbines”, and “can also be lowered to the ground during hazardous weather
such as hurricanes” [4].
Determining if Your Property is Suitable
The overall power output of a wind turbine varies greatly depending on the specific
location, with differences in wind speeds and quality making large variations possible on a site-tosite basis. In order to maximize the wind power production the wind flow source must be steady
and uninterrupted. Nearby obstacles such as structures, forests, and uneven terrain (sharp slopes)
cause significant turbulence, which “results in less effective wind speed, lowers power production
and causes unnecessary wear and tear” on the rotor [8]. Consequently, turbulent winds increase the
frequency and amount of maintenance required and “contributes to machine failure” [8], which is
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why turbines must be located in consistent, laminar flow paths in order to minimize costs and
prevent the failure of the project.
The first step an individual should take when even considering a small wind turbine is to
determine the annual average wind speed for the site being considered. This data can come from a
variety of sources, all with their own level of accuracy, however the more sources considered the
better, as consistency in data will only help to build a better idea of the wind patterns in the area in
question area. Ideally, the best option is to “install a data-logging anemometer (wind meter) at the
same height and location as the proposed wind turbine, and let it run for 3 to 5 years” [7].
Unfortunately, this method is often far too time consuming and expensive for a small scale wind
operation, and the time period is often shortened to a 1 year time frame, which is considered to at
least “give you some idea and is the absolute minimum for worthwhile wind information”,
however is still “too short to be very reliable” [7]. The far cheaper alternative to determine a
ballpark figure for the local average wind speed is by consulting resources such as “a wind atlas
(or wind resource map), meteorological data, airport information and possibly the local vegetation”
[7], as trees in windy spots tend take on “sloped”, or wind-swept shapes known as vegetation
flagging. [9]
If the decision is made to measure the wind at the site itself and an anemometer is installed,
the data collected (over 1 or more years) should be compared with that of the “nearest airport or
meteo-station for that same year” [7] (data must be corrected to hub height, as airport
measurements are often only taken at a height of around 30ft. [9]), in order to determine if the site
is “more or less windy than that airport or meteo-station, and by how much” [7]. This can then be
used to give a better understanding of the overall average wind speed when compared to the longterm wind speed data available from the airport/meteorological site, and will help make the shortterm anemometer data far more useful in understand what to anticipate over the long term. A final
option for determining or confirming your local average wind speed is to “obtain data from a local
small wind system” nearby if the data is available. [9]
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Ultimately, wind turbines are generally only productive as an energy source in more open,
rural areas with few obstructions, and have a very difficult time performing in more denselypacked, urban and suburban settings.
The various structures and tall buildings
of a crowded city offer many obstacles
to the wind and result in very turbulent
air flows, destroying almost all of the
Figure 2: Disturbed Wind Envelope Around Obstacles [10]
potential for energy generation. This requirement for open flat areas is one of the reasons why
offshore wind farms are becoming more prevalent, and most on-shore wind farms in north
America are located along the shores of the great lakes or in the flat regions of the mid-west, as the
flat, open, and unobstructed space provides a smooth, laminar source of wind as a fuel supply. If
the site in question for the wind turbine meets the requirement of a mostly flat, obstacle free area,
the general rule of thumb in choosing in appropriate location is that the wind turbine should be
situated a minimum of about 150 metres (500ft) from any obstruction and the lowest blade tip
point should be at least 10 metres
(30ft) higher than any obstacles in
the surrounding area [8, 10]. If the
property to be built on is free of
Figure 3: Turbine Height and Clearance Requirements [10]
obstacles, but does not satisfy the
flat land requirement, it may be beneficial to use the land to your advantage and locate the turbine
near the top of a gradual ridge. Big wind farms can be commonly found located “on ridges in
gradually sloping landscapes” [8] as the wind actually tends to increase in wind seed as it
approaches the top of a gradual
ridge due to incompressibility and
flow patterns, potentially even
more power obtainable thanks to
Figure 4: Wind Speed Over a Ridge [10]
the boost in wind speed.
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Sizing Your Turbine
If you live in a rural area that is exposed to strong and consistent wind, and there is no
connection to the electricity network, then it may be cost effective for you to install a small scale
wind turbine. Small wind turbine systems typically used in residential applications “range in size
from 400 watts to 20 kilowatts” [11], depending on the specific energy requirements of the site,
but most households normally “use micro wind turbines that are smaller than 5 kW”, while “small
communities or groups of houses might use turbines up to 20 kW”. [6]
In order to help determine what size turbine is required, the first step is to “establish an
energy budget” [11]. Focusing on energy efficiency and minimizing the actual electricity used at
the site allows the use of a smaller turbine to satisfy the same energy outputs. Considering
additionally, that “energy efficiency is usually less expensive than energy production” [11],
reducing the site’s electricity use prior to selecting a turbine size “will probably be more cost
effective” in the long run [11].
According to the US Department of Energy, “a typical home uses approximately 10,766
kilowatt-hours of electricity per year (about 897 kilowatt-hours per month)” [12]. Therefore,
“depending on the average wind speed in the area, a wind turbine rated in the range of 5–15
kilowatts would be required to make a significant contribution to this demand” [12] . If there is
any difficulty in determining size requirements for a specific site, or other questions regarding
operation, the wind turbine manufacturer, dealer, and/or installer should be consulted, as they be
able to “help you size your system based on your electricity needs and the specifics of your local
wind resource and micro-siting”, as well as provide information regarding “the expected annual
energy output of the turbine as a function of annual average wind speed”, and “the maximum wind
speeds at which the turbine is designed to operate safely” [13].
Going Off the Grid
Depending on the circumstance, such as those in in remote locations or those who live near
the grid and wish to obtain power independence or commit to non-polluting energy sources;
powering homes or small businesses via a small renewable energy system not connected to the
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electricity grid (a stand-alone system) “makes economic sense” and “appeals to environmental
values” [14]. Specifically for the cases of remote locations that are not necessarily close to a
distribution network, these stand-alone systems can offer a “more cost-effective” alternative to
extending the necessary power lines to the electricity grid, “the cost of which can range from
$15,000 to $50,000 per mile” [14].
A successful stand-alone system tends to utilize a combination of technologies and
strategies to generate reliable power at minimal costs. Typical approaches could include the use of
generators which run off fossil fuels, and/or renewable hybrid systems utilizing a combination of
wind and solar energy supplies. However, regardless of the approach chosen, one of the most
important aspects to focus on in order to implement a successful stand alone system is “reducing
the amount of electricity required to meet your needs” [14]. By first focusing on the efficiency of
the whole system, and eliminating waste, the entire system can then be designed to meet this
reduced load, reducing the additional cost that would come with a larger system. This is especially
critical for off-grid systems, as “the lower efficiency of a turbine tied to batteries, and the losses
involved in charging batteries” [7] already substantially drop the production level compared to that
which is expected, so every extra effort put in to minimize the amount of energy needed to be
generated works towards the most efficient use of the collected power still available.
Furthermore, in order manage a series of intermittent energy sources and back up energy
sources in an off-grid system, an additional investment in "balance-of-system" equipment in order
“to condition and safely transmit the electricity to the load that will use it” [14].
This equipment varies depending on whether the system is grid-connected, stand-alone or hybrid,
but typical off-grid systems include components such as: “Batteries, Charge controller, Power
conditioning equipment, Safety equipment, Meters and instrumentation” [14]. Each of these
components have their own specific function in monitoring and managing the system. For instance,
the charge controller’s principal function is to prevent overcharging of the battery bank. By closely
monitoring the batteries level of charge, the controller can recognize when the bank is fully
charged, and can then dump excessive energy from the battery bank to a diversion load. These
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charge controllers can often be found “built into the same box as the rectifiers” [5] saving the need
to purchase an AC-to-DC converter, however a power inverter will likely be a necessary
investment to convert the stored DC energy back into the typical AC supply found in most
households. It is also required that some form of overcurrent protection (fuses, relays) be present
between the battery and controller/dump load to prevent damage in the case of a current spike, or
short-circuit/fault [5].
Energy Storage
Although wind will never cease to exist, it’s presence in specific locations is never
continuous and provides many difficulties when trying to obtain and steady and continuous power
source. More often then not the wind will not be blowing at sufficient levels to generate the
electricity required at the moment needed. Contrarily, because wind turbines produce electricity
whenever the wind blows above the cut-in speed, at other times the wind will provide a surplus of
power at an interval when very little power is required, such as night time. As a result, off-grid
energy systems require a means of storing the energy generated so that it can be used at a time
when it is needed, not just when it’s available. The most common means of achieving this energy
storage for small wind turbine systems is through the use of battery banks; groups of batteries
wired together, typically sized on a site specific basis, but ideally large enough “to keep household
electricity running for one to three calm days” [5]. Additionally, a battery bank must also “be of
sufficient size to be able to cope with the potentially high current draw of the inverter” [15]. The
size of battery bank varies depending on the
specific site needs, but typical bank sizes
and their accompanying inverter size can be
found summarized in Figure 5.
Figure 5: Inverter Size vs. Battery Bank Size [15]
Lead-acid batteries are the most common choice of battery used in off-grid systems due to
their deep-cycle properties, with flooded lead-acid batteries typically the cheapest choice, but
having a trade off with increased maintenance as opposed to typical lead-acid batteries, requiring
the need to occasionally replenish the water lost during the normal charging process [5]. Although
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lead acid batteries are the most common, there are many options to choose from in order to fit the
specific site or system needs, such as Sealed gel-cell batteries, whose freeze-resistant qualities
offer advantages over temperature sensitive lead-acid batteries in unheated spaces; or Sealed
absorbed glass mat (AGM) batteries, which “are maintenance free and designed for grid-tied
systems where the batteries are typically kept at a full state of charge” [5]. Battery choice is critical
to achieving an effective off-grid wind energy system, so it is recommended to consider the
specific site needs when determining which battery is best, and only use deep-cycle battery types,
as their ability to “discharge and recharge 80% of their capacity hundreds of times” make them the
most effective option for remote renewable energy systems [5, 12].
Grid Integration
A grid-connected small wind energy system allows for homes or small business to be
powered with renewable energy during periods of resource availability (wind, sun, etc…) while
allowing any excess electricity produced to be fed back into the grid and sold for a surplus, or used
to offset the cost of electricity for periods when the renewable energy system cannot meet demand.
Because energy is used when needed and supplied when available this type of system off requires
no means of energy storage, “eliminating the expense of electricity storage devices like batteries”
[16]. In the case of a battery-less grid-tie systems, the connection setup and components needed
changes slightly to reflect the electrical requirements and safety needs of the electrical grid. For
instance, there is no more need for a charge controller, since the inverter is pumping whatever
energy is generated by the turbine back into the grid according to whatever agreement has been
finalized with the local power provider [5]. However, some additional equipment will also be
needed in order to provide quality energy to the grid, such as voltage regulators and specific gridtied inverters capable of converting the wind energy supply to an AC current and synchronizing
the electricity produced with the grid’s “utility grade” AC electricity, allowing the system to feed
wind electricity to the grid at the quality expected by the utility [5]. It is also critical that the proper
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safety devices and disconnects are in place in to allow for
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these systems to be disconnected and isolated from the grid
in case of maintenance or local faults, as well as adequate
power conditioning equipment to ensure that the power
produced “exactly matches the voltage and frequency of
the electricity flowing through the grid” [16] and to
prevent the power supplied by the generating source from
effecting the balance of the entire electrical grid.
Typical equipment used and various connection
Figure 6: Small Wind Turbine Configurations [17]
setups can be found summarized in Figure 6.
Though the ultimate success of the system will still be based on the proper installation and
operation of the turbine itself, deciding on a grid-connected system can make the most sense if [18]:

Local electrical prices are high (10 to 15 cents per kilowatt-hour).

Requirements for connecting to the grid are not prohibitively expensive

Good incentives are available for the sale of excess electricity/purchase of wind turbines.
Additionally, grid-tied systems are capable of being designed to operate with or without
batteries. Allowing for the ability to supply back up power in case the grid goes down for period of
time, or utilize the energy available from the gird when convenient and renewable resources are
scarce. Although this allows the benefit of being able to recognize advantages from both types of
systems, the trade-off is that the balance of system, power-conditioning, and safety equipment of
both systems are required for effective operation, increasing the initial costs of the system, and
increasing the complexity of the setup.
Economics
The initial investment in a small wind energy system can be a costly one depending on its
desired purpose, required sizing, and which incentives are available, however according to the US
department of energy, “the average cost of small wind projects installed in 2017 was
$10,117/kilowatt” [12, 19]. When then considering that wind turbine would need to be rated in the
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range of 5–15 kilowatts to make a significant contribution to the average annual household energy
demand [12, 19], it is likely that initial costs for a small wind turbine system will be upwards of
$50,000 at the very low end.
Another cost which must be taken into account is the ongoing maintenance costs required
to keep the turbine operating properly. Due to the many moving parts and highly variant forces
being applied to the turbine on a daily basis, the reliability of small wind turbines is problematic,
and often require frequent maintenance or part replacement to ensure the turbine is functioning at
full capacity. These annuals costs are typically estimated at around 1% of the initial cost of the
installation, but can increase drastically depending on the circumstances [17]. Unfortunately,
because of the characteristic nature of the turbine needing to be mounted as high as possible,
getting at the turbine to actually perform maintenance can be a problem. The costs of crane fees, or
“having turbine installers hang off the top of a tower for long periods of time” [7] are not small
ones, and will quickly eat into the systems maintenance budget, sky-rocketing the overall costs,
and making an economically feasible small wind energy system difficult to achieve. In order to
avoid these costs, and make the feasibility of a small wind energy system far easier to realize, it is
recommend to mount your turbine on a tilt-up tower, as opposed to a fixed one. Tilt-up towers
work by allowing the system owner to tilt the tower over and lower the turbine towards the ground
in order to perform the required maintenance from the ground, making maintenance and repairs
much safer and cheaper [7]. Another way to save money on maintenance costs is to develop a good
knowledge of the system as an owner. Understanding how the system works, how to safely stop
the turbine, and how to perform routine maintenance/trouble-shooting can help to eliminate
unnecessary and costly technician visits and keep the system economically feasible.
Small ‘off-grid’ wind energy systems tend to make the most sense if the site currently has
no grid-connection, as the cost for connecting to the electrical network can run as high as around
“$25,000 per km” [6], making the cost of connecting a remote system to the grid too high for the
system to be feasible. If the site already has a grid-connection available, it is likely most
economically feasible to implement a grid-tied system. Although battery prices are falling,
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purchasing a large enough battery bank to store the energy required to meet demand for the
average house “won’t make economic sense for most households that are already grid-connected”
[6].
Grid-tied energy systems on the other hand can offer several advantages to off-grid systems
from an economic standpoint. If the grid connection is already available and connecting to the
network does not incur substantially expensive fees, then a grid-tied system offers a number of
options in reducing electrical bills and achieving a reasonable payback for the system. Connection
to the grid requires the entering of an agreement between the owner and the grid provider. The
agreements are variable depending on the location and provider, but are typically broken down into
two main payment schemes. A net purchase and sale arrangement consists of “two uni-directional
meters” being installed: one of which registers electricity drawn from the grid, while the other
monitors the electricity generated at the site and fed into the grid [16]. The downside to this
arrangement is that the cost of electricity supplied to the site by the grid is at the typical retail rate,
while prices received for generation of electricity supplied to the grid are at a wholesale rate. It is
possible and even common for there to be a significant difference between these rates, leaving the
small wind energy generator with the short end of the stick, paying a reduced price for the
electricity used, as opposed to directly recognizing the full benefit of the generated energy itself. A
far more advantageous arrangement for the system owner is to enter into a net metering
arrangement, which consists of a “single, bi-directional meter” that monitors both the electricity
drawn in from the grid as well as the electricity generated by the system that is fed back into the
grid [16]. The difference between the amounts of energy consumed and generated at the site are
then determined at the end of the pay period (typically monthly) in order to determine the bill.
Excess energy consumed by at the site is charged at the typical retail prices, while net surpluses of
energy provided to the system are paid for at the wholesale rate similar to the net purchase and sale
agreement.
The advantage of the net metering setup stems from the fact “that the power provider
essentially pays you retail price for the electricity you feed back into the grid” [16], however these
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arrangements are not available in all localities and available options should be investigated in the
analysis stage prior to installation in order to gain a true understanding of the economic feasibility
of the proposed system.
Main Challenges/Drawbacks of Wind Energy
The biggest drawback for wind power is characteristically intermittent nature of the
resource. Even if the proper research is done prior to installation and the best location for the
turbine is chosen, the wind is highly variable and will never blow at a steady speed continuously.
Consequently, small wind turbines systems are not often the used as the sole energy supplier to a
site, and usually require being combined with other methods of energy generation. This could take
place via the system being “connected to the main power grid in a net metering arrangement” [3],
or in the form of a hybridized off-grid power system combining various forms of energy
generation such as solar, hydro, fossil fuel generators, etc. This highly fluctuating wind input is
one reason why a large percentage of small wind turbines underperform significantly, frequently
achieving energy productions around half of that which was expected, with numerous studies
showing the turbine efficiency often even falling short of that [7, 8, 20, 21, 22]. This poor
operational outcome is also commonly caused by the selected site not having a wide enough
clearance envelope, creating a more turbulent air supply than expected [8], increasing the stresses
on the blade and upping the losses experienced by system. This can have a huge effect on the
production of the system for the relationship between wind speed and power output is that of a
cubic nature, mean a reduction in wind speed by half reduces the actual power produced to oneeighth of its original output. Consequently, “lost wind speed through poor siting or tower height” is
a costly error for the owner [8]. Although average wind speed should be able to be determined
using various resources as discussed previously, the turbulence of the air flow is often a difficult
factor to predict and is another reason why a successful wind energy system is not achievable for
all individuals, specifically without carrying out detailed analysis prior to installation.
Additionally, if the chosen system has been designed to be connected to the grid, it will
likely necessitate the signing of an interconnection agreement with the local power provider that
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may require the owner to carry liability insurance to “protect the power provider in the event of
accidents resulting from the operation of your system”, as well as potentially “indemnify them for
any potential damage, loss, or injury caused by your system”, while other fees and charges may
also be included in this agreement such as “permitting fees, engineering/inspection fees and
metering charges (if a second meter is installed)” [16]; potentially making the convenience of a
grid tied system quite costly.
Other drawbacks to wind energy can include the increased number harm/death of birds and
bats, as well as adverse health effects from excessive noise and phenomena such as “shadow
flicker” [23], including, sleep disturbance, headache/migraines, stress, hearing problems, tinnitus,
heart palpitations, anxiety, and depression. All of which potentially contribute to an altered quality
of life [24]. Many of these factors contribute to the large “minimum distance” standards for large
wind turbines from populated areas (550m [25]). However, the actual legitimacy of these effects
are still questionable as the results of most studies investigating these effects are often are often
conducted in the manner of a self-reporting survey, meaning they are “subject to bias”, and often
“tend to correlate with negative political or personal attitudes toward wind turbines” leaving the
results inconclusive [26]. Fortunately, these types of issues are more characteristic of large,
industrial sized turbines and tend to have very little effect on the small wind turbines discussed in
the scope of this paper.
Conclusion
The generation of renewable energy as opposed to the use of fossil fuels is critical
component in the battle against climate change, and as a result it can appear as if any means of
renewable energy is superior to conventional methods. However the intermittent nature and
inability to control these wind as a source of energy means that the likelihood of the feasibility and
ultimate success of a small wind turbine system depends on a number of factors. The most
important of those factors is the location and geography of the proposed site. Without a sufficient
wind resource to supply the system with an energy input, the project will never be feasible
regardless of how efficient or well-maintained the system may be. The easiest ways to determine
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the magnitude of the wind energy resource in your area is to consult online wind energy maps,
local wind data measurements and the installation of a wind monitoring device at the site in
question to confirm the figures between these various resources.
If after analysis have been completed, it is decided to proceed with a small wind energy
system installation, it is highly recommended to consult a professional or contact an expert. There
are many minor details that go into a wind energy system installation that can be easily overlooked
without prior experience. Connecting a small wind turbine to the electrical grid, requires prior
approval, so it is necessary to contact the local lines company and electricity retailer before
beginning installation [6]. Having a knowledgeable expert at hand to spearhead the installation can
ensure that these sorts of steps aren’t passed over in the implementation of the system, causing
costly issues and delays down the line.
Additionally, it is critical when planning a wind energy system to invest in a quality turbine
and mount it on the tallest tower possible. This will undoubtedly raise the initial costs, but the
improved durability and high quality energy production will pay off in the long term. Attempting
to save on initial costs by investing in cheap equipment or smaller towers will only serve to
substantially increase maintenance and part replacement costs while simultaneously providing
significantly lower energy production for the turbines useful life, making a worthwhile system
difficult to achieve. Although a quality turbine will reduce the amount of maintenance required
over its lifespan, the constant rotational motion and varying forces applied to the blades and the
tower on a day-to-day basis will take their toll on the turbines operational health. Therefore, it is
very important to leave room in the budget for maintenance costs, as regardless of the quality of
the turbine, some sort of upkeep will be necessary in order to help keep the system running at peak
effectiveness. [6]
The utilization of a small wind turbine system can make good sense if there are rebates or
other incentives available in your area. It is recommend to do thorough research on this subject
prior to installation so as to help get a better idea of exactly how far the planned budget can go.
Often federal incentive plans can be found online, but it is also recommended to contact the local
power provider or municipal government to see if there what may be available at the local level.
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These sorts of offers can be found from a nationwide, to a highly localized basis depending on the
site’s location and can help make small wind turbine systems more affordable and feasible.
Overall, although the implementation of a small wind energy system can be an effective form of
energy generation, however the ability to achieve a successful, worthwhile system can be difficult
to attain, and tends to be a particular dependant on the specific site. If proper analysis of wind
resources are done prior to installation, and a suitable location is chosen with a sufficient wind
available to meet energy demands, a small wind energy system can be a reliable way of generating
energy for the purpose of an off-grid system, or to minimize electrical costs and offer supplemental
energy in case of a black-out as part of a grid-tie system. However, for the general case, small
wind energy systems can be fairly expensive, often significantly underperform from their expected
outputs, and require relatively frequent maintenance in order to maintain their operational
effectiveness.
It is likely that a far simpler and cheaper [27] way of producing reliable, renewable
electricity would instead to be to invest in solar-electric modules [5]. These sorts of solar-electric
modules offer the advantages of no moving parts, making them essentially maintenance-free, and
the ability to generate energy at almost any location, as long as they are positioned in the sunlight.
Additionally, there is also the option to combine the best of both of these renewable
resources in a type of hybrid systems. These sorts of systems utilize solar, wind, and often a
combination of other energy sources (i.e. conventional fossil fuel generator) in the same sort of
system described previously in this paper, in order to provide reliable and effective power
regardless of which resource is available, all while utilizing whatever resource is most convenient
and abundant when it is available [28].
Consequently, it is highly recommended to explore all renewable energy options available
before deciding on a solely on a small wind energy system.
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