Tuesday, 2 July 2013

More accurate wind power average calculations.

Been trying to get this trough to Wolfram Alpha, but their forum doesn't really get used and the FB page, like all pages now, is pretty much set up for ineffectual broadcast only. I'll put it out here to see if any of yall has input.

Basically there's a problem with how most people figure out the viability of home wind power in their area, which is that they'll take the average windspeed (let's say 15 km/h), figure a turbine's power output at that speed, and thereby see how much the turbine will put out per week/month/year.
And if the wind's blowing at a constant 15 km/h then that will be accurate. Let's say about 12 watts for a typical meter diameter turbine.
But, if the wind's actually not blowing at all half the time (0 watts), and at 30 km/h the other half (98 watts) then the actual average power output is gong to be 49 w, not 12. If it's 60 km/h a quarter the time it'd be 195 w.
It's because wind power goes up by the cube function of its speed. A little more wind makes a lot more power, and just taking the average (mean) speed doesn't at all accommodate this, so people are making the decision on whether to invest in a turbine based on erroneous information.

So what I'd like to see is a calculation in Wolfram whereby the windspeed data for an area is graphed for a given period, the area under the graph, ie the total wind power, is calculated, and a windspeed average given such that that's how fast the wind would have to be constantly blowing to give you that much power.
People can then multiply that by the output of their turbine and see if it's going to be a viable investment for them.