Watts Whatt?
Having trouble figuring out the technical specs of your appliances and how and what to expect from a portable wind turbine? You're not alone!
It's one of the questions we're most frequently asked, and it has a multitude of answers, so we've assembled a little guide, to help you understand the difference between Watts (W) and Watt hours (Wh). One is power, the other is energy, but which is which and what does it mean? Hopefully, this article will shed some light on the matter!
Let's start with a look at The Wind Catcher
The Wind Catcher is a compact wind turbine capable of generating 200W at 6 m/s or 4800Wh within 24 hours.
But what does that mean?
Assuming that the turbine is spinning at a perfectly steady pace in 6 m/s winds, the display would read 200W. Watt is the power we are extracting at this very moment! If we let the turbine run for one hour, we've produced 200Wh of electricity. Let it run for another hour, and we've produced 400Wh. If we keep it going for 24 hours, we get 4800Wh.
(200W x 24h = 4800 Wh).
Watt hours is a term used to describe how much energy has been produced or used in one hour, that we can then multiply with the hours using or producing, and the result is the total amount of energy in the given amount of hours.
However it is unlikely that the wind blows steadily at 6 m/s for 24 hours. The direction of the wind shifts, slows down and picks up again, and so on! On the display of the Windcatcher, we're more likely to read; 175W, then 214W, 153W, 199W, and so on, which makes it hard to tell how much energy is actually produced.
Luckily, looking back we can see how much energy we've produced. Say we've had our Wind Catcher spinning for 24 hours with a reading of 4800Wh, we simply divide Wh with the time spent, to end up with an average of 200W.
(4800Wh / 24h = 200W)
In the graphic below we see the correlation between the wind speed and the Wattage output in one hour:
Notice how the power (Watt) flattens even though the wind picks up, beyond 5.5 m/s. At a glance it might seem like potential energy goes un-utilized, but in fact it is a measure set in place to ensure steady and reliable energy, especially in low winds.
...but we promise to keep it short!
We need to introduce you to Volts and Amps. Afterwards we'll stick with Watts and Watt hours, in order to keep it as simple as possible.
Ampere
Amps, short for amperes, measure the current or the rate of flow of electricity. It's analogous to the volume of water flowing through a pipe each second. Higher amps indicate a greater number of electrons flowing through the circuit at a given time. Think of it as the width of the opening in the pipe; a wider opening allows more water (electrons) to flow through each second.
For larger storage devices it is the norm to use Watt hours to describe capacity. Many battery devices such as power banks or phones the capacity is usually defined by Ampere hours (Ah) or mili-Ampere hours (mAh) and technically is defining capacity but depending on the voltage the Wattage changes.
Volts
Imagine voltage as the pressure. It's the electrical force that pushes electrons through a wire. Think of it like water pressure in a pipe. Higher voltage signifies a stronger push, causing electrons to flow faster and with more force. Household outlets in North America typically provide 120 volts, while car batteries have around 12 volts.
Furthermore Voltage differs around the world and depending on where you live, the appliances will usually be rated for 120V or 220V. These appliances are meant to be plugged into the outlets at home.
Most car batteries will have a 12V output, but some trucks and buses have 24V or even 48V.
There's so much more to unwrap, when talking about electricity, but let's hold off with the advanced physics lesson, and get back to the matter at hand;
Watts and Watt hours!
In order to put our energy to use, we use a battery. These come in many shapes and sizes, but most common are lithium-ion or lead-acid batteries like the ones you find in most cars or a portable power station.
For our example, we'll be using a portable power station, with a capacity of 1000 Wh. Running our Windcatcher as we did before, we can calculate that it will take us 5 hours to fully charge it.
(1000Wh / 200W = 5 h)
If the winds are slower and we're only averaging 150W, it will take us 6 hours and 40 min.
(1000Wh / 150W = 6.66 h)
...so for the sake of simplicity, we'll be using the 12V output on our power station from here-on out!
We've charged our power station and we're ready to use the sustainable energy that we've produced.
We're going to plug in a mobile cooler rated at 47W using the 12V output.
(1000Wh / 47W = 21.28 h)
With continuous usage we will have depleted the power station in a little over 21 hours.
Now let's plug in something a little more power hungry, like a microwave oven rated at 700W.
(1000Wh / 700W = 1.42 h)
This tells us that the microwave can run continuously for a little under one hour and 30 mins.
It is important to note, that microwave ovens are notorious for using a lot of power, but then again - when was the last time you ran a microwave for an hour and a half!?
As mentioned, the wind doesn't blow with a perfect 6 m/s anywhere! Not outside a wind tunnel at least.
The Wind Catcher produces 200W at 5.5 m/s, and it will continue to produce 200W even when the wind picks up. This is due to its pitch mechanism that turns the blades to ensure longevity as well as safety.
Instead of a perfect 6 m/s, we prefer to use an average of 6 m/s. This means that if the wind drops below 5.5 m/s, the power output will be lower than 200W, and if it goes above 5.5 m/s, the power output will remain at a steady 200W. So in the course of 24 hours the overall output will be less than 4800Wh.
Years of data from vigorous testing shows that an average wind of 6 m/s in 24 hours will produce 4500Wh. Still enough to keep our 47W cooler running for almost 96 hours!
And don't forget; The Wind Catcher will continue to top up the batteries as you're cooling your beverages!
The
Wind Catcher
What makes
The Wind Catcher
stand out?
:: A KiteX explainer ::
Birds
vs.
Wind turbines
:: A KiteX explainer ::