solar + wind turbine installation

System

Please advise....

24v install
1) 2 80w 12v panels in series - I am planning to install a 10 amp fuse/breaker between the charge controller and the battery, there's a fuse between battery and load. The question is should I be putting another 10 amp fuse/breaker between the panels and the charge controller?

12v install
2) 2 80w 12v panels in parallel and 250w wind turbine - is a 40 amp fuse/breaker between the charge controller and battery adequate and also would you install a fuse between the wind turbine and charge controller and between the solar panels and charge controller?

mike95490

Re: solar + wind turbine installation

I don't think you can feed the PV and Wind gen into the SAME charge controller. They each require different controllers.

The controller for the solar PV can just throttle back when the batteries get full.

The controller for the wind gen uses a "dump load" or "diversion load" [ a water heater element or bank of lights ] to keep a load on the wind gen, otherwise the blades will overspeed without any load at all.

The 2 controllers can be wired to the same battery bank, and if the controller does not have a built-in fuse, you should install a fuse for each, in case the controller gets sick and tries to drain the battery too fast.

System2

Re: solar + wind turbine installation

Hi Mike,

Thank you for your reply, the 12v charge controller is a Rutland HRSI that states it can take the wind turbine and 160w peak power of solar PV.

mike95490

Re: solar + wind turbine installation

mrboot wrote: »

Hi Mike,

Thank you for your reply, the 12v charge controller is a Rutland HRSI that states it can take the wind turbine and 160w peak power of solar PV.

http://www.marlec.co.uk/hrsispec.htm says nothing about the dump load capacity.

Anyway, what will decide your voltage mostly, is the wind conditions. If you have low winds, 12v is the only way to go. If you have really high winds, then you could load the turbine better with 24V . (slow spinning turbine only puts out low voltages)

I'll back off now, because I'm at the limit of what I know.

Solar Guppy

Re: solar + wind turbine installation

Note from the link Mike provided

Not a real product only a CAD rendering wrote:

Notes:
1. Solar panels must be fitted with diodes

This is a generic PWM controller ( which is NOT the way to regulate a wind genny ). Its a single input that requires a diode to have a solar panel parrallelled with the wind input.

It would probably be fine because the only "250 watt" wind gennys are the Air X brands and they only output about 100 watts in a hurricane

PS: forget the diode and then the panel becomes the dumpload for the Air Genny ...

autoxsteve

Re: solar + wind turbine installation

Solar Guppy wrote: »

...It would probably be fine because the only "250 watt" wind gennys are the Air X brands and they only output about 100 watts in a hurricane...

Very good response....

System2

Re: solar + wind turbine installation

Hi Solar Guppy,

The installation is a marine installation and I require knowledge!

2 voltages on board...

1 x 24v - runs fridge and navigation lights

1 x 12v - runs LED lighting, pumps, small inverter


3 battery banks - engine (24v), 12v, 24v

12v charged by 2x80w panels + Rutland 913
24v charged by 2x80w panels + alternator

I have 2 charge controllers at present

1 x Steca 30amp charger for the 24v system
1 x Rutland HRSI for the Wind Jenny and 2 x 80w panels


Is the Rutland HRSI the best controller for the job or is putting the panels and wind jenny with this controller and blocking diode the wrong way....


back to the original question....

do I need fuses/breakers from the charge source to the charge controller?

BB.

Re: solar + wind turbine installation

Mr. Boot,

You need to look at the where the high currents are available and what would happen if something (anything) failed.

For example. Your battery is typically the highest available source of current. Say you had a 30 amp charge controller connected to the battery. You would have a ~40 amp fuse between the battery and the charge controller protecting 40 amp wiring.

From the 30 amp charge controller, you you connect three 8 amp solar panels in parallel (everything is made up here--just for sake of discussion).

Each of those 8 amp solar panels can feed the 30 amp charge controller with a total of 24 amps (3x8amp)... No problem there. Assuming your wire is sized to flow 40 amps where the panels all connect, and your controller, if it failed is protected by a 40 amp fuse from the battery.

However, you look at your solar panels and they require a 10 amp fuse for protection... So, now each of those solar panels should have a 10 amp fuse in them, because if one shorted, the other two would output 16 amps total--more than a single shorted panel is rated to safely manage...

Each circuit and device, you have to play these "what if" question out. What happens if a wire shorts. What happens if a device shorts, what happens if a charge controller shorts, etc...

So, in the case of the 3 solar panels above--yes you would need three fuses.

In the case where you have a battery 10amp fuse, charge controller, then 8 amp wind turbine (with wiring rated for 10amps+ between the 10 amp fuse all the way to the wind turbine), the one 10 amp fuse would be sufficient. If anything shorted, either the 10 amp battery fuse would pop, or the 8 amp wind turbine would be supplying ~8amp maximum to a shorted wiring harness--and no wiring would overheat (and a 10 amp fuse would be pretty much meaningless, because the 8 amp wind turbine would not be able to output enough current to blow a 10 amp rated fuse).

By the way, typically, you want to run a circuit at 80% (maximum) current of the rated protection fuse. Running a fuse at near 100% of it rated current will cause the fuse to blow (within minutes to days/weeks--all depending on the exact fuse specs., temperatures, etc.).

Generally the manuals of the wind turbine, charge controller, etc. should all have wiring diagrams that call wiring specification and protective devices.

Does this help?

-Bill

System2

Re: solar + wind turbine installation

Bill,

Thanks for your help, makes things a lot clearer - the documentation supplied with the panels (BP 380U) and wind turbine is a bit "sketchy", when it comes to protective devices and blocking diodes.

Solar Guppy

Re: solar + wind turbine installation

If a charge control requires a blocking diode, you don't want that charge controller, that's one of the functions it should provide and its will be more efficient than an external diode ( charge controllers use mosfets for that function )

adas

Re: solar + wind turbine installation

Aloha, I have been mixing my windgennys and PV this way.

My 2 identical windgennys are directly wired to 1/2 each side of a 24v 800AH battery. They are unregulated and are not enough to overcharge the 2 x 24v 800 amp/hr batteries that I have in parallel. Then I have two MX-60's each regulating 1200 watts of PV. The PV system just "tops off" whatever the Windgennys cannot accomplish. Since I have about a 500w constant average load the batterys never are overcharged by the windgennys.
frank

System2

Re: solar + wind turbine installation

That is an interesting solution.....I will be reconfiguring my wind/PVs this summer so I can have power all year for my off-grid cabin. I just finished the radiant heat installation.

I will not be staying year round but I want to keep the heat on so my main concern is .... what if my "average" load goes away? Seems like I would still need some sort of dump load for the gennys, nes pas?

niel

Re: solar + wind turbine installation

just noticing this from adas,
"My 2 identical windgennys are directly wired to 1/2 each side of a 24v 800AH battery."

if i'm reading this to mean 1 12v wind genny charging the first 12v battery in a 24v seriesed battery bank and the 2nd wind genny charging the 2nd 12v battery in a seriesed 24v battery bank then this could setup inequalities in the overall charge to it seeing it as a 24v battery with one battery getting more or less than the other. topping it off with solar will not right any inequalities the seperate wind gennys have created and could conceivably go beyond being correctable even with an eq charge from the pvs.