Wind / Sun Solar Controller

Re: Wind / Sun Solar Controller

In general, finding a "combined" solar+wind charge controller is not going to be a good idea (and there are not many, if any, good quality wind+solar charge controllers).

Solar panels can use "series" type charge controllers. I.e., need charging current, turn on the switch and current flows from the solar array to the battery bank. Battery full, turn off the switch. All is fine.

With most horizontal axis wind turbines (that traditional types of turbines) need loading of the battery bank all the time. If you disconnect (turn off) the connection to the battery, even in moderate winds, most HAWTs will over speed and self destruct. So, the "standard" wind controller is a "shunt" (or "dump") type controller. You connect the controller to the battery bank and when the batteries are full, the controller turns on and sends the current to (typically) a resistance heater (air or water) to prevent the battery from over charging.

You can mix controller types (series or shunt) on the same system. Or, you can even connect your solar+wind turbine directly to the battery bank and use just a shunt controller (large enough load to sink both full sun and full wind output).

But--The details are that shunt controllers do not do a very good job at "properly" recharging a battery bank.

Series controllers are available in two different types--PWM (pulse width modulation or "on/off" switch) and MPPT (maximum power point tracking--a digital power supply that can efficiently take high voltage/low current from the array and "down convert" to low voltage/high current for the battery bank). For various reasons, many times MPPT series controllers are almost required for many types of solar arrays.

So the typical solar+wind system would have a PWM/MPPT solar charge controller plus a shunt (or two shunt controllers for safety) controller to dump excess wind power.

And to make things even more complex, there are MPPT series controllers for Wind Turbines too (you can dramatically increase the output of a wind turbine with the proper MPPT type charge controller--does a better job of "matching" the current/voltage (IV) profile (curve) of the turbine to the IV curve of the battery bank).

Lastly, I am not a big fan of small wind. You need to have a tall tower in a pretty windy region to harvest "useful" amounts of power from a wind turbine. And most commercial small wind turbines are not worth the money to even install (tower, concrete, wiring, electronics are usually way more expensive than the wind turbine itself).

So, for most people, Solar + Backup (gasoline/diesel/propane, etc.) backup generator are better investment of time and money. At that point, if you still want to research/try wind, you can always add it to your system.

We have a few people here that have wind systems and are very happy with them... but they live in regions that have poor winter sun and/or flat prairie (plains) with very high average wind speeds. Usually, you need to mount the turbine on a 18 meter tall tower minimum (really 27 meter or taller tower) and well above any local obstructions (buildings, trees, etc.).

One interesting way to find your minimum tower height is to fly a kite and see how high it need to get for "clean" air flow. Flying a wind turbine in turbulent air will cause its useful output to fall to near zero.

I can give you links to some good charge controller companies--But you are 1/2 a world away. You probably have easier access to Chinese/Asian charge controllers.

There are a lot of PWM (simple) "cheap" solar charge controllers out there. Some of them even work pretty well (look for good metal case with heat sinking--plastic cases do not let the heat out and therefore the electronics tend to fail pretty quickly). MPPT type charge controllers--There are fewer companies out there that make these complex (and more expensive) charge controllers in Asia. And many of the "MPPT" Asian charge controllers are just PWM types that have "MPPT" stenciled on the outer case.

Anyway--Before you buy any solar/wind equipment--Do you have a good idea about your power usage? Have you "conserved" as much energy as possible (it is almost always cheaper to buy very efficient appliances and conserve vs trying to generate solar/wind/fossil fuel power).

Once you know your power needs (and how much sun you get by month/season), then we help you size the battery bank and solar array. From there, you can start looking at the best hardware for your needs. Solar RE systems are not easy (or cheap) to expand. It is better to design the system to your loads vs just purchasing hardware, wiring it up, and see what happens.

-Bill

Re: Wind / Sun Solar Controller

Remember it is "layered" power here... If your outages are less than 1-2 days--Then the battery bank will be fine with AC charging.

If you go 2-14 days solid without power once every few years, a good Honda or Yamaha "Inverter/Generator" is hard to ignore (or even some other non-inverter generators too). Just run it for ~6 hours or so every day or two to keep the batteries reasonably charged until the power comes back.

Otherwise, you are looking at solar arrays--Which make much more sense if you are using them for 9+ months of the year or must have power for a month/longer power outage.

Power is a highly personal choice. But money to do things can be a deciding factor on how you approach your "ideal" solutions.

In California, for small amounts of power, around $0.10 per kWH... For folks with A/C and businesses, they can pay upwards of $0.50 per kWH in the summer afternoons.

-Bill