Some of the frequently asked questions on wind turbines include; do wind turbines work without wind?
Why don’t certain wind turbines spin despite the windy conditions? Can they be harmed by too much wind?
A wind turbine is a tool used to harness the strength of the wind and utilize it to create electricity. Due to their similar appearance and fundamental operation, they are frequently confused with windmills.
All of these gadgets share the potential to harness and transform wind energy for practical purposes. For different uses, there are different sizes of wind turbines.
How Wind Turbines Work
Kinetic energy can be found in the blowing wind. A wind turbine’s blades “catch” the wind when they are perpendicular to its direction of flow, turning it- similar to how sailboats propel themselves forward using the wind.
The blade is designed to revolve when pushed against by the wind, which tries to push it out of the way.
Blades And The Rotor
Most wind turbines have two or three blades. The wind will cause the blades to turn more quickly if it applies the same force in the same direction to all of them.
The rotor connected to the blade rotates along with it. The rotor of the generator is turned by this motion being transmitted through several cogs in a gearbox.
Gearbox
Before being transmitted to the generator, the gearbox is intended to magnify the rotations of the wind turbine blades. The electricity produced could be distributed through power plants or consumed on the property itself.
The Effect of Wind’s Direction on Wind Turbines
Though prevailing winds can be forecast for a certain place, the direction the wind will blow is not always predictable.
The wind direction can change due to unforeseen atmospheric low- and high-pressure developments.
The wind must be perpendicular to the turbine blades for them to “catch” it. If not, the wind will pass by the turbine blades instead of rotating them.
Or the blades might not be able to fully harness the wind’s energy. Less energy will be produced because of decreased blade rotation.
So, how do we resolve this?
Utility-scale wind turbines include built-in wind detection systems that can sense the wind’s direction and move their faces to position the blades to capture the wind’s full energy.
Anemometer and Wind Vane
A wind vane and anemometer are placed on top of the nacelle to measure the direction and force of the wind. This data is processed by the built-in controller to determine where the blades should be placed.
It starts the motors that will eventually turn the nacelle and the blades linked to it in the desired direction. We call this a yaw.
Yaw System
The yaw system controls how the wind turbine’s rotor and blades are oriented to the wind.
How Much Wind Does It Take for The Blades to Turn?
The wind turbine’s construction eliminates all wind resistance. The blade will turn even in the presence of a light breeze.
However, the amount of electricity produced is inversely related to wind speed. The wind’s strength determines how quickly the blades turn and how much electricity is produced.
This means that at slow wind speeds, the wind turbine might not be profitable and efficient enough to produce enough power. According to experts in wind energy, wind turbines require a certain minimum wind speed to operate well.
A place must have a minimum yearly wind speed of 9 mph.
On the other side, greater wind speeds are required for a wind turbine to be viable. Only when the location’s yearly average wind speed exceeds 25 mph can the installation of a wind turbine be profitable.
Does a Wind Turbine Operate in The Absence of Wind?
If there is no wind, a wind turbine cannot produce any electricity.
Wind turbines cannot function in the absence of wind.
But most of the time if there’s not enough wind, the wind turbine will be so slow. The wind is dynamic; it can blow more forcefully at times, blow softly at others, or even appear to be completely calm.
So, what happens to the turbines during these situations?
In truth, the challenge (due to wind fluctuation) is how to calculate the viability and economics of erecting a wind turbine while considering the “variable” feature of wind.
Standalone/Independent Wind Turbine
If there are no plans for energy storage or backup in the case of a freestanding wind turbine, there may be issues with the power supply.
This problem can be solved by using a net-metering connection to a grid. Strong winds will force the wind turbine to produce more electricity than is required.
And this extra energy will be exported to the grid. On the other side, you can always use the grid to make up the difference when the wind is weak.
And the wind turbine isn’t producing enough energy. A battery is an additional option for storing extra energy produced while the wind is stronger – to be utilized later when the wind is weaker.
Utility-Scale Wind Turbines
Utility-scale power distribution networks don’t rely only on the wind as the energy source.
Typically, coal-fired thermal power would form the foundation of a power distribution network. Hydroelectric, solar, and nuclear energy may also be used as inputs.
Through the net-metering system, inputs from individual users are added to the grid in addition to the inputs from wind farms, solar farms, and power plants.
In general, the increased energy output from another location may make up for any downtime experienced by the wind turbines in one location. For instance, offshore wind turbines might be operating harder to make up for onshore wind turbines that aren’t producing electricity.
To solve this problem, install wind turbines scattered over various locations. In this manner, a constant total wind capacity from all locations can be ensured.
Even though it might surprise a layperson to learn this, wind in a certain area can be predicted fairly accurately several days in advance. Regardless of whether it will be windier or less windy, this offers power planners adequate time to modify alternative power sources to satisfy the power demand.
Final Thoughts
The bottom line is wind turbines are designed to function in the presence of moderate to strong wind flowing in a favorable direction. So, technically, wind turbines cannot work without wind.
However, in a utility-scale network, solar batteries can be tethered to wind turbines.
References
- https://www.1energysystems.com/how-do-wind-turbines-work-when-it-is-not-windy/
- https://www.portablesolarexpert.com/how-to-connect-wind-turbines-and-solar-panels/
