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Solar Hot Water

Tracker 1&2

Array 3

Control Center

Wind Turbine







Currently building dual axis tracker with kit from Windy Nation to rack 6 230W panels and run them as two strings to our Midnight Solar Classic charge controller. This is our first solar not run through a Sunny Boy inverter, (inoursystem), and intended to further demonstrate differences in charge architectures to visitors touring our project. And a great use for the Classic we bought to run micro-turbines and found out there was so little generation we took the whole dual turbine tower down. We used the Classic for a while on our Whisper 500. It worked great and gave us a way to watch the output on our computer, but in the end I built a whole new charge control for the Whisper, because the original SWWP controller was really poor and broken most of the time. FYI, the Classic and the NES controller withstood lightning strikes that blew out our SWWP controller and both of our stock Wattsun Tracker electronics. I installed all new components for charge control into the SWWP Whisper 500 transformer box.

New layout of Whisper 500 turbine charge control. The Midnight Solar Classic unit is mounted for control of our current PV project as yet not completed. The inside showing layout of bridge rectifier, Flexcharge controller, and solenoid for external load control.

Note the bridge rectifier. A very heavy duty unit made for DC welding. This Flexcharge by NES is tried and true, the controller has withstood test of lightning and time controlling our micro-turbines for 4 years. It watches battery voltage and connects the original SWWP load dump resistors directly into the turbine AND battery bank when voltage goes over 56.5 VDC. This configuration protects my batteries from anything that might cause voltage spikes from the turbine AND from any other sources. It also allows the turbine to spin and not be subject to extreme shorting out as if turbine were directly hooked to the resistance load by its self, which is similar to shorting out the turbine with a brake. No doubt this architecture is easier on the yolk and brushes inside the turbine. We have had failures of these turbine parts in the past. Controlling battery voltage is so important, we plan a second, (backup), controller and separate load dump. Maybe two smaller dumps set to slightly different parameters so the load dump works in smaller wattage increment stages. Using the redundant systems as a failsafe at the same time.

The heavy duty solenoid. Battery and turbine combined on one side and load dump on the other side. They connect only when voltage goes over 56.5 VDC.

We need to set any possible charge parameters within the system below this value by at least 0.5 volts, so the load dump doesn't connect during boost, equalize, or float.

I have noticed if grid power fails during sunny conditions, the battery voltage may spike in the high, (60's), until the SI's and SB's respond. This configuration seems to control the voltage spike much better, and gives the SMA equipment time to react to grid failure.






December 26, 2012. This is as good as generation gets with a Whisper 500 3.2 KW wind turbine in real life. Our storm winds have been 25 MPH, gusting to 40 MPH all night. Still, there are moments of low wind as well. 10.9 KWH, all from the Whisper turbine, at 7:19 am. In truth there are moments of up to 3 KW generation from the turbine, but SMA grid tie equipment tends to average the peaks and troughs of generation somewhat into real grid feed data. Long story short, in real life under perfect natural wind conditions, with winds that sometimes furl the turbine, expect 1.5 KWH/hour generation. Here is where a Kestrel 400 would be superior. No losses to furling.

Daily output for the month of December. Blue is total generation, wind + solar. Red is wind generation only. This December has been the lowest generation per nameplate KW in 5 years. The graph for 2012 is below. January I had internet connection issues which is why the output seems so low. Really we had about 1000 KWH in January.




Copyright 2007 Earthbilly Organics