We are a Net Meter system now. That means more data to record and I'll have to walk out to the meter pole every morning to retrieve the net results. Got array 3 up and running just in time! I feel we have entered a new chapter with connection to grid yesterday. I want to thank the people from Black River Electric for always being positive and helpful throughout "OUR" first grid tie experience. I will report net meter readings in the morning, after night time consumption. The wind turbine has failing main bearings, half way to normal replacement, and must be taken down again for repair.
AUGUST TOTALS; Total grid feed 947.36 KWh, 174 KWh more than we used. Total tracker production 545.14 KWh. Total fixed array 385.71 KWh. Total grid feed from turbine 16.51 KWh. Now lets create a production factor for each watt in our system.
Tracker production = 545.14KWh/3120w = 0.175 KWh/watt/August 09.
Fixed array production = 385.71KWh/2970w = 0.123 KWh/watt/August 09.
Do the math and we get 35% greater generation from tracker mounted wattage. I might as well calculate the turbine generation factor as well...
Turbine grid feed production 16 KWh/3200w = 0.005 KWh/watt/August. Granted, this has been one of the poorest turbine generation months on our record. We will compare this to a future winter month soon.
With the Solar Production Factor you can calculate how much solar PV wattage you need to install to offset your electric usage. If you need 650 KWh, then for the month of September in SE Missouri, you would need 650/0.101(fixed array)= 6.435 KW solar PV fixed array. September 09 was a poor generation month compared to August 09. This data will be better after a full year of collection. For August 09 650/0.123= 5.285 KW solar PV fixed array. After a couple more months of data I will dedicate a page to the data set spread sheet.
8/1 Net this morning is 00000. The battery has been maintained at my preset voltage of 51.6 VDC all night. When I reconfigured my system for grid tie I had intuition I should drop my battery charge parameters dramatically, and so far that seems very correct. I set float to 51.6 v. Boost and full to 52.6 v. and equalize to 54 v. I have VRLA batteries, a deep cycle glass mat jell design that require very low charge rates. The bank now has 93% full capacity and should stay that way except for grid failures, when the bank will supply power for backup and our AC island, a 1000 amp hour at 48v whole house UPS. I feel, now, there is no need to increase bank size. At 7:05 our system started feeding grid with the excess power not needed by the house, thanks to tracker 1 & 2. It sure looks like turbine generation is shed into the grid feed. I had to turn down the charge rate again to offset battery soc still increasing. The soc is already at 96%. I adjusted the float and full to regulate at 51.0 volts and a few hundred watts arriving through the turbine seem to go elsewhere and the voltage stops increasing at 51.1 v. Yes, just watched the turbine turn up to 8 amps for a minute and the battery voltage maintained 51-51.1. Then as the turbine slowed the voltage dropped slightly to 50.9 and reestablished at 51.0. Also understanding that without wind, only a 0.6 amp charge is keeping the bank at 51.0v. And again, the turbine spun up to 7 amp and the bank voltage stayed at 51.0 We are grid feeding our excess solar and wind power. Net meter 99989, fed 11 kwh over house demand. Battery bank 95% Total grid feed 21.9 KWh. Trackers 12.9 KWh. Array 3 9 KWh. Turbine production 0.86 KWh. water at 112F.
8/2 6:00, Net meter 99996, (it started at 00000 and went backwards). Battery soc still 95% so the charge rate is adjusted correct now at 51-51.1 volts. 19:20, Battery soc still 95%. I think I will report only morning Net Meter and report generation each evening. Total grid feed 39.092 KWh. Turbine production 0.01 KWh. Trackers 23.7 KWh. Array 3 15.382 KWh. Water at 134F. Just about as perfect a solar power day as we can get.
8/3 6:05, Net meter 99987, 13 KWh in the grid, about a full day without the air conditioner running. I happened to get up about 2:00 and glanced at the turbine panel and noticed pritty good generation going into the grid for a few moments before the wind died down. I checked Sunny Island control at 6:28 and the battery bank dropped 1%, so I raised the charge control setting 0.1 volts, to 51.1 VDC. Total grid feed 28.764 KWh. Trackers 16 and array 3 12.8 KWh. Turbine production 0.55 KWh. Water at 135F.
8/4 6:00, Net meter 99996. I let the air conditioning run during the night. Total grid feed 22.578 KWh, Array 3 10 KWh. Turbine production 0.61 KWh. I turned up the battery bank voltage to 52.5 because of continued soc decrease.
8/5 Net meter 00001. Total grid feed 25.72 KWh. Array 3 10 KWh. Turbine production 0.07 KWh. Water at 120F. The new battery float voltage of 52.5 is keeping the soc topped off but costs 100 watts continuously out of the grid all night if there is no turbine generation. Some of that 100 watts is to power the Sunny Islands.
8/6 Net meter 00012. Please realize this is the peak power usage season for our home. We run a 27,000 BTU 240 VAC air conditioner to cool 2,400' of living space. And still our solar power system is keeping up with demand in spite of 90+ daytime temperatures. Total grid feed 25.83 KWh. Array 3 11 KWh. Turbine production 0.02 KWh. Water at 122F.
8/7 6:00, Net meter 00008. Total grid feed 36.25 KWh. Array 3 separate, 14.19 KWh. Turbine production 1.94 KWh. Water at 130F. The trackers generated 20.46 KWh, array 3 14.19, turbine 1.94 KWh. All three very similar 3 KW size generators. We generated back some surplus on the net meter today. Water at 125F.
8/8 6:00, Net meter 99999. Total grid feed 37.178 KWh. Trackers 21.47 KWh. Array 3 14.1 KWh. Turbine 1.6. The air ran mostly all day today. Water at 131F.
8/9 Net meter 00004. Total grid feed 36.459 KWh. Trackers 21.92 KWh. Array 3 14.23 KWh. Turbine 0.30 KWh. Water at 129 F.
8/10 Net meter 00007. Total grid feed 21.74 KWh. Cloudy all day and still over 20 KWh. Turbine production 0.50 KWh. Water at 120F.
8/11 Net meter 00017. Total grid feed 25.84 KWh. Trackers 14.16, array 3 11.57, turbine 0.1 KWh. Water at 118F.
8/12 Net meter 00032. A couple days of clouds and heat behind us. 20:29, We gained back some net today. I'll report in the morning, after a nights consumption. Total grid feed today 34.93 KWh. trackers 21, fixed array 13.8, turbine 'squat', a highly technical, possibly German word, for nearly nothing. I noticed a whining sound from the turbine today. Don't know if it was just the wind or if the stator bearings may already be failing. I will keep an eye on it. Water at 128F.
8/13 Net meter 00012. The wind turbine has a bearing problem and has to be taken down. Total grid feed 37.8 KWh. trackers 22.88, fixed array 14.9, turbine 0.01. Water at 130F.
8/14 Net meter 99998. Total grid feed 32.6 KWh. Trackers 19.75, fixed array 12.86, turbine 0.01. Finally got the last fixed array panel in and is now ready for first light in the morning. Water at 130F.
8/15 Net meter 99989. Total grid feed 36.5 KWh. Trackers 21.6, fixed array 14.92, turned off the turbine because the bearing noise is so loud I can hear it at the house. Net meter this evening is 99970, and the air cond. ran cold all day and evening. Water at 124F.
8/16 Net meter 99985. Total grid feed 34.24 KWh. Trackers 20.01, fixed array 14.23. Water at 120F.
8/17 Net meter 99982. Total grid feed 25.1 KWh. Trackers 14.2 KWh, fixed array 10.6, and a little from the turbine, I couldn't resist turning it on with a storm arriving.
8/18 Net meter 99991. Total grid feed 21.31 KWh. Trackers 11.18. Array 3 9.84, turbine the rest. Lightning from a storm this evening has activated the turbine failsafe reset. I must go out and reboot the turbine system.
8/19 Net meter 99998. Total grid feed 30.34 KWh. Trackers 16.69, fixed array 12.76. Turbine 0.89.
8/20 Net meter 00000. Total grid feed 13.12 KWh. Trackers 4.3, fixed array 5.8, turbine 3.1. I knew the fixed array would out generate the trackers on a cloudy day when the trackers don't move.
8/21 Net meter 00000. At 13:01 today I saw the system grid feeding 7,959 watts, a combination of clear air and a good wind for the turbine. Total grid feed 38.14 KWh. Trackers 20, fixed array 13, turbine 5.
8/22 Net meter 99976. Total grid feed 35.29 KWh. Trackers 19.45, fixed array 12.84, turbine 3.
8/23 Net meter 99950. Cool clear weather and no air conditioner running. Total grid feed 33.07 KWh. Trackers 19.77, fixed array 13.3, turbine none.
8/24 Net meter 99926. Total grid feed 38.6 KWh. Trackers 22.84, fixed array 15.76, turbine none. Water at 145F.
8/25 Net meter 99897. A hundred and three KWh to the positive, with a couple more cool clear days in the weather forecast. Total grid feed 38.5 KWh. Trackers 22.73, Fixed array 15.77, Turbine none. Water at 140F.
8/26 Net meter 99872. Total grid feed 35.04 KWh. Trackers 20.48, Fixed array 14.56, turbine none.
8/27 Net meter 99857. Total grid feed 33.03 KWh. Trackers 19.22, fixed array 13.8, turbine none.
8/28 Net meter 99852. Total grid feed 13.8 KWh. Trackers 6.766, fixed array 6.335, turbine 0.699.
8/29 Net meter 99858. Total grid feed 33.77 KWh. Trackers 19.609, fixed array 13.865, turbine 0.296.
8/30 Net meter 99848. At about 8:00 the grid power went off for two seconds. The system responded perfectly by stopping grid feed and then resumed after several minutes of resynchronization. So log this as a test! Total grid feed 39.095. Trackers 22.49, Fixed array 15.706, turbine about 1.
8/31 Net meter 99826. Total grid feed 21.8 KWh. Trackers 12 KWh fixed array 9.8. Turbine none.
MONTHLY TOTALS back at the top of this page.
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