combining hydro and solar

Re: combining hydro and solar

What is the no load voltage of your hydro? Just wondering, mine is almost 60 volts no load and I run it through a MPPT controller with great success. The MPPT unit usually loads down the cross-flow turbine to about 30 volts, then down-converts the voltage to 12, and ups the amps. The higher voltage is great at reducing line loss from the turbine to the battery shed. It also finds and locks on, at the max power output RPM.

Re: combining hydro and solar

TheBackRoads wrote: »

Don't mean to get off topic.... But how does the function of a MPPT in a hydro setup work.. Do you still need a diversion load?

With my tiny settup, Max 60 volts open circuit/no load and an average 165 watts, no I don't need a diversion load, the controller handles it exactly as it would solar. Most micro hydro systems, if the load is removed, will experience such RPM runaway that they not only produce voltages beyond the handling capacity of the controller, but could cause mechanical damage to the turbine/generator itself, thus must be kept under constant load. Such is not the case with my cross-flo turbine, so it's no problem using the MPPT, and in fact the MPPT does it's normal sweeps causing the turbine to sweep through a range of PPM, then locks onto the speed that results in the highest output. In effect, electronically matching the turbine/alternator for the highest wattage output. I'll take this a bit further, into what could be uncharted territory - - - that may surprise some people. Initially, I never expected to ever surpass perhaps 75 watts at most from hydro, so the Morningstar Sunsaver MPPT appeared the perfect choice, and it worked perfectly beside the MX-60 controlling the solar. But in time, with tweaking and improvements in the pipeline etc, the output, when the water level was high, after heavy rains, increased head and thus output to sometimes in excess of 200 watts, the max of the Sunsaver, causing it to go into what could be a sort of safety mode. For whatever reason, overpowering, or some other defect, the Sunsaver finally croaked, so now I'm waiting for the TS MPPT-60 to arrive. In the meantime, I've just jumpered a wire from the hydro to parallel the solar input to the MX-60 and believe it or not, the match between my hydro and solar is close enough that the MX functions normally, not knowing the difference between the hydro settup I have, and the solar input. In daylight it does it's normal sweeps and functions as if only the solar existed, and at night it sweeps the hydro and continues to operate normally, just doesn't go to sleep for the night.
In the early days of my hydro, when it's output, including no load voltage were much lower, the MX-60 would get all confused in the daylight, not reliably able to lock to the MPP of PV, thus the second controller. But now, with the higher hydro voltage more closely matching that of the solar input, the MX has no problem at all. Amazing. But yes, when the new controller arrives, the hydro and solar will each have their own controller again. Good to have backup, + I do worry about lightening storms and that long run of wire to the hydro. If I'm around, or wake up when there's lightening, I pull switches and hope for the best.

Re: combining hydro and solar

stephendv wrote: »

I noticed on my TS 60 MPPT that you can program it as a wind controller, and can then enter a handful of static MPPT set points instead of using the dynamic sweep of the solar MPPT function. This may be better suited to hydro use too.

AWESOME! Thank you for that info! Once the best MPP is found, there is indeed no need to continue repeated sweeps with my hydro system. I appreciate your post.

Re: combining hydro and solar

I plan to use a 4" electric butterfly valve, that closes slow enough to not get a water hammer. This will also preserve my water pond when the sun is useful.

Re: combining hydro and solar

mike90045 wrote: »

I plan to use a 4" electric butterfly valve, that closes slow enough to not get a water hammer. This will also preserve my water pond when the sun is useful.

I like that idea. I have to take a small hike to manually close the gate which also allows the pipeline to completely drain so it won't freeze if I shut it off for any reason in Winter. Last two winters there was enough water in the lake to let it run 24/7 till Spring. Summer is dryer, so shut it down during daylight to conserve water.

Re: combining hydro and solar

Thanks, I see how your setup now works and the reason behind what your doing!