I recently had a reader complain about the performance he was seeing out of his PMA (Permanent Magnet Alternator) wind turbines he purchased from Missouri Wind and Solar. He said their units were not producing close to the power that the company claimed and he said he was getting zero support from the company. His videos are below:
And so after doing research, I realized he wasn't the only one having problems with their PMA wind turbines from Missouri Wind and Solar.
After doing a little of looking around on YouTube, I found this hilarious video of a PMA wind turbine and a guy who thinks he is producing a lot of power, but really isn't producing much power at all.
He's excited about 3 Amps, but the voltage is only at 14 V, which means he's producing less than 75 Watts, barely enough to power 1 incandescent light bulb? But this amperage is only instantaneous, and it usually hangs around zero. So maybe over the 3 minute video he has produced enough energy to keep a bulb on for about 10 seconds!!!
Missouri Wind and Solar tries to impress people with a graph of power output vs. RPM, but users don't need to see RPM, they need to see power output vs. wind speed, or at least a table showing how the RPM's vary vs. wind speed?
In the above video, Jeff keeps saying "look at all those Amps" but remember, you don't care about instantaneous Amps, you care about total energy produced, which is Amps multiplied by Volts multiplied by time (for more info on this, check out our post on What is a kWh). In the video, at about 18 mph, there are 3 turbines connected to produce a max of 125 A at about 15 V for a total of 1.875 kW. Since there are 3 turbines connected this comes out to an average of 625 Watts per turbine. But remember, these are just during the wind gusts.
Over the 3 minute period of time that Jeff is looking at his Volt and Amp meters, I would guess that the average Voltage is about 13 V and average Amperage is about 30 Amps (and that is being generous). So if we assume these were the averages, his 3 turbines were producing about 390 Watts, or 130 Watt per turbine.
Maybe it's just me, but this is not that impressive.
This excellent video on YouTube shows why PMA wind turbines just don't live up to their rated claims:
Here's the point: Many of these small wind turbine dealers and promoters will try and impress you by showing you graphs and videos of their turbine's voltage, or amperage when the wind gusts, or how fast they spin, or how many unicorns their turbine can power, but there is only one value you need to be concerned with: Power output vs. Wind Speed. You then need to consider what the average wind speed is in your location and only then can you decide if a wind turbine makes sense.
You don't care about instantaneous amperage output when the wind gusts. You care about total power output of the wind turbine, and as I covered in my post on Solar PV vs. Wind Turbines, wind turbines just don't make sense for almost all locations in the U.S. because the average wind speed just isn't high enough. You don't need gusts of wind, you need steady, strong wind to produce a lot of energy from wind turbines. Don't get suckered in by "fancy" YouTube clips.