Wind power is one of the few viable sources of alternative energy that are available to homeowners today. It’s especially popular in areas that have regular high wind seasons. However, it’s important to consider not just the natural circumstances that are going to affect your wind turbine’s power generating abilities, but also the technical aspects involved.
One of the most important characteristics to look out for in a wind turbine is its power rating. This is usually measured in kilowatts (kW) and is similar to a vehicle’s horsepower. The power rating pretty much tells you how big the turbine is so that you can get an idea of how much energy it can produce. It’s important to note here that the kW rating of a wind turbine is not necessarily an indication of the device’s energy output capacity.
How much electricity does a wind turbine produce?
The simplest way to explain what all this means is to make an analogy. You know how your energy bill is measured in kilowatt-hours (kWh)? This basically represents a combination of the power that’s been used multiplied by the amount of time during which that power was used.
For instance, let’s say you have a 100-watt light bulb in your living room and you happen to leave it switched on for 10 hours straight. During that time period, it would have used something like one kWh. Conversely, industry experts estimate that a 10kW wind turbine energy system has the potential to produce up to 10,000 kWh worth of energy per year. However, this estimation is based on a turbine that’s operating under favorable conditions, which won’t always be possible in real life.
The reality is that there will be days, weeks and even months where there just isn’t enough wind for your turbine to produce this amount of energy. On some days it will only be able to generate a small fraction of its expected energy output. A soft breeze is not enough to power a wind turbine and extreme heat will render it practically useless.
The best way to calculate how much electricity does a wind turbine produce is to multiply the air density with the mechanical efficiency of the turbine. Then, multiply the answer by the length of the rotor blade and the speed of the wind.
Wind speed is one of the most fundamental determining factors to how much power does a wind turbine produce. It’s more important than the turbine’s mechanical construction actually. Although the use of wind turbines has picked up among residential areas all over the U.S., most areas in the country just don’t experience the amount of wind needed to power a turbine consistently. It doesn’t matter which brand or manufacturer you buy your wind turbine from, it won’t generate much power if the weather conditions aren’t favorable.
The U.S. Department of Energy is a great resource to consult on this matter, and it shows the average annual wind speed at 50 meters above ground. If your area has wind speeds that are below the 10 miles per hour threshold then your turbine simply won’t generate the power you need to effectively run your household.
However, if the average wind speed increases marginally to 12 mph then you can expect to experience a significant boost in the amount of energy that’s generated by your wind turbine.
Another factor that contributes to how much power does a wind turbine produce is altitude. The higher you place the turbine the more power it will generate. For example, a wind turbine that’s placed on a 100-foot tower will produce 30% more energy than a wind turbine that’s placed on a 60-foot tower. The numbers will improve even more if you make sure that there are no obstructions around or near the turbine, such as trees or other structures.
A common concern among homeowners wanting to purchase wind turbines is that the rotor blades will fall off and hurt someone during high winds. Luckily, most manufacturers factor this into the production process, as most wind trines shut down automatically whenever wind speeds reach the 25 mph threshold. Needless to say, wind energy is not a viable option for areas that only generate seasonal windstorms while remaining relatively calm most of the time.
When it comes to size, wind turbines with larger rotor blades tend to generate more energy than turbines with smaller blades. While it may not seem like much of a difference, a 10-foot rotor blade can generate 58% more energy than an 8-foot blade.
The thing to keep in mind when looking for a wind turbine is the quality of the components that are used to manufacture the turbine. Avoid manufacturers and brands that boast about power production while providing little to no information about the parts they use.
How Much Energy Does a Windmill Produce
The power rating assigned to a windmill is never set in stone because its performance is determined by the weather conditions that it operates in. We all know that wind conditions change from season to season and from one hour to the other.
A good example of the variability of wind power versus wind rating is the Cape Wind Project. This project involved the installation of 130 wind turbines in Cape Cod. These turbines were expected to generate about 468 megawatts worth of wind power. However, in reality, they will only be able to generate 170 megawatts due to the weather conditions on the site.
Both estimates were produced from examining and observing the annual wind levels of the site on which the turbines were to be installed. It’s important to have this information before installing the wind turbines so that the turbines can be strategically placed to generate the maximum amount of energy. It will also help determine how much energy does a windmill produce.
In order to create electricity from the wind energy that has been harnessed, the turbine uses machinery that’s hidden behind the blades. The turbine also contains a gear system that it uses to accelerate the speed at which the blades rotate. This is to facilitate electricity production by transforming the mechanical movement of the blades into usable power.
How Many Homes Can a Wind Turbine Power
Wind energy experts tend to measure a turbine’s expected output according to the number of homes that it can power. The Energy Information Agency reports that on average, U.S. homes consume about 10,656 kWh worth of energy every year, which translates to 888 kWh per month.
Meanwhile, an average wind turbine that’s working at optimal capacity would be able to generate enough energy to power 332 homes per year.
With that said, it’s important to keep in mind that actual wind power almost never corresponds to projections. That’s because demand and supply almost never match up and the weather conditions don’t always allow for turbines to operate at maximum capacity.
So finding out how many homes can a wind turbine power is a matter of trial and error for the most part, as projections can only go so far.
Also keep in mind that household electricity use only accounts for 1/3 of the total annual electricity consumption.