We’ve gotten numerous questions regarding our two wind turbines since the second one (#2) was installed recently. The most recent wind turbine (#2) was installed to supplement electricity consumed by the Water Treatment Plant to reduce the monthly electrical bill. Before Wind Turbine #2, the average Water Treatment Plant electric bill averaged $3,000.00 to $4,000.00 monthly and sometimes higher in dry weather. Wind Turbine #2 is just now coming fully online and we won’t know the actual estimated, averaged savings until after a few months of billing.
Number 2 Wind Turbine came on line in the early part of October 2014. However there was an electrical problem with the electrical generator causing a failure within the first week. This generator is inside the top nacelle behind the blades. This repair was completed November 17th which is the reason it was not seen running for most of October through middle of November.
During this time it was also discovered there was an electrical configuration mismatch with the incoming power at the Water Treatment Plant on the AEP side. This was corrected by AEP the same week the generator was replaced in Wind Turbine #2. To answer that question: Yes, the replacement generator was a warranty replacement. Since November 17th Wind Turbine #2 has been in operation but with periods of not operating primarily because of fine tuning needed in the software to better fit the environmental conditions of our area dealing with sudden wind direction changes that are common this time of year. By now you should notice it is getting more running time due to those software tuning for tracking the changing wind directions. It’s not perfected yet, but getting much better during this initial run-in time.
Number 1 Wind Turbine was installed at the Waste Water Treatment Plant to supplement electricity consumption by the Waste Water Treatment Plant to reduce the monthly electrical bill. Before Wind Turbine #1, the average Waste Water Treatment Plant electric bill averaged $2,500.00 to $3,000.00 monthly and sometimes higher in wet weather. Since Wind Turbine #1 came online in February 2012 the average electric bill has been $1,000.00 to $1,800.00 monthly. During high winds, this turbine sometimes produces more electricity than the Waste Water Treatment Plant requires and it is returned to the electrical grid and the City gets this as a reimbursement credit on the quarterly electric billing. This quarterly credit averages around $500.00. Selling this back to the grid is not automatic and required application with the Retail Provider. The reimbursement rate is about two cents to four cents per kilowatt hour. We are in process of obtaining a similar arrangement for Wind Turbine #2 should it produce more than the Water Treatment Plant needs.
Like Wind Turbine #2, #1 (in 2012) experienced issues with optimum, continuous operation (software) during about the first four months as well as other equipment malfunctions resulting in very similar questions because it wasn’t turning.
The most common question we’ve been asked about Wind Turbine #2 is something like: “Why is it (Wind Turbine #2) stopped while the other one (Wind Turbine #1) is turning?” Other than the software fine-tuning required to optimize operation during this initial running phase which caused stoppages, there are inherent operational differences between the two in the way they operate versus wind speed – wind speed is the key to the answer for this question.
For both Wind Turbines it is a given that the higher the wind speed the more power produced and the lower the wind speed the less power is produced. Most of the questions about #2 not running versus #1 running usually come at a time when wind speeds are very low. I hope the below information provides the basic answer to this question and how they are different, especially in low wind speeds.
Wind Turbine #2: When wind speeds are low – around 6mph to 7mph – #2 turns itself off because it is producing ZERO kilowatts and won’t re-start until winds are about 10mph to 11mph.
Wind Turbine #1: When wind speeds are low – around 6 to 7mph – #1 keeps leisurely rotating, BUT it also is producing ZERO kilowatts even though it is turning. It will turn itself off when winds get below 3mph to 4mph and won’t re-start until winds reach about 6mph to 7mph.
The bottom line is this: Whether turning or not, with winds below 9mph (yes this is more than that 6-7mph), each wind turbine’s production is so small and unmeasurable for all practical purposes production is ZERO kilowatts.
Another question usually revolves around “How much are they producing”? Both wind turbines will produce near 90% to 100% peak power – both are rated at 100kw – at the very highest, steady winds above 28mph to 31mph. Likewise, they will automatically shut themselves off when wind speeds exceed pre-determined design limits – each is different. As to the power produced: Number 2 had a peak kilowatt output of 90kw between the January 7 – 9 period – but too early to collect trending and average data over such a short time. Number 1 had a peak kilowatt output of 95kw for the same period of January 7 – 9. This was a time when wind speeds had steady peaks of 30mph and higher during that same period.
Wind Turbine #1 has produced a total of 480,000kwh since February 2012. Time will tell us how well #2 will do over the next 6 – 12 months and we should be able to have more useful data on which to make valid estimates rather than our initial guesstimates.
If anyone has other unanswered questions or wants more details, they are free to come visit me at City Hall when I am in.
