connecting a 12v turbine to a 24v system

[Aspire]

So, hey everyone. So, i have a small setup (less then 100w) in my shed setup for projects and as a learning ... thing. In my area, Wind is super "profitable" but solar, not so much. however, how would i go about connecting a DYI 12v turbine to a 24v system? Would i need a 12v->24v step up? or how would i do this?

[jflorey2]

So, hey everyone. So, i have a small setup (less then 100w) in my shed setup for projects and as a learning ... thing. In my area, Wind is super "profitable" but solar, not so much. however, how would i go about connecting a DYI 12v turbine to a 24v system? Would i need a 12v->24v step up? or how would i do this?

I'd say the opposite is true - solar is a lot more "profitable" (in kw per $) than wind. But in any case:

If it's a DIY 12V turbine, then either change the windings or the diode configuration to increase your voltage at your desired rotor speed. Alternatively change the blade pitch to increase speed.

[SunEagle]

I am not sure if solar is always better than wind.

If you are located way North and on a lake or wide open plain you more than likely will get a pretty constant wind and very little sunlight all year round. So in some cases a wind turbine if designed and installed properly might be better.

[Aspire]

Ah. Yes, i live wayyyy up north, canada to be exact. Edmonton area isnt the best for solar, so i decided to go with a 6m(mast height) wind turbine attached to my shed as a experiment. It cost me... probably 100$ in steel, the alternator, and the wiring to get it going. jflorey you live in cali don't ya? ( har har )

[Wy_White_Wolf]

What type of alternator?

WWW

[jflorey2]

If you are located way North and on a lake or wide open plain you more than likely will get a pretty constant wind and very little sunlight all year round. So in some cases a wind turbine if designed and installed properly might be better.

If the bolded part of your statement is followed - agreed. Unfortunately, in my experience, more than 50% of wind installations are done with small machines on short towers.

To put it another way, if you are going to go cheap, solar will generally be cheaper and more reliable - even in "bad" solar areas.

[SunEagle]

If the bolded part of your statement is followed - agreed. Unfortunately, in my experience, more than 50% of wind installations are done with small machines on short towers.

To put it another way, if you are going to go cheap, solar will generally be cheaper and more reliable - even in "bad" solar areas.

I agree. IMO a DIY wind turbine installation requires a lot more thought, design and money to work and provide the power expected.

Those small turbines are pretty much a waste of time even if installed high on a pole. Best to let the experts do it for you.

[KMac]

My small (400 watt) 24v turbine, mounted 30 feet up, does an excellent job of supplementing my 1kw solar panels for my weekend cabin. It is on the prairie with few obstructions except a single line of trees 150 feet to the South (not prevailing winds direction).

I have a 1/2 hp well pump running on a timer (low volume well) filling a couple of water tanks and a drip line pump running, so I need at least 1.6 kwh daily. I'd be in trouble after about two or three cloudy days without the wind turbine, since my batteries only hold about 7.5 kw. Wind usually kicks up when there is no sun. So, if I can get ten hour of wind generating at 100w, that is very, very helpful in that calculation, and so far it tends to do that or more. Plus, it's fun. Solar has no moving parts (one of it's advantages, but less entertaining).

So, my practical experience is that it can be very beneficial if, like everything else here, the source exists (be it sunlight, wind or water), and you design it right to meet your goals. Granted, on the very simple comparison, in most longitudes on the small scale, solar will win head to head, in terms of energy produced per dollar. But that is a limited if not entirely false comparison when one benefit you seek is diversification of energy sources given limited storage. In that situation, it can be helpful to have a secondary source that tends to be productive in times when your primary is not. It can be smaller, and more trouble and cost per watt produced, with the understanding that not all watts are of equal value, as they are worth more during periods of scarcity (cloudy days, short days, etc. on solar).

So, the OP's question remains, can he use a step up device from a 12v turbine to a 24v battery? I've wondered the same thing. Anyone know?

[bcroe]

So, the OP's question remains, can he use a step up device from a 12v turbine to a 24v battery? I've wondered the same thing. Anyone know?

You need a 12V to 24V DC transformer. In fact this can be done (bidirectionally) using a switched capacitor converter. I haven't
seen it done on this scale, good project for someone to design. Bruce Roe

[jflorey2]

So, my practical experience is that it can be very beneficial if, like everything else here, the source exists (be it sunlight, wind or water), and you design it right to meet your goals.

Glad it's working for you.

So, the OP's question remains, can he use a step up device from a 12v turbine to a 24v battery? I've wondered the same thing. Anyone know?

Sure, there are several ways to do it. The Genasun charge controller is probably the "safest" - it will output a set voltage and its MPPT tracker won't bog down the turbine or cause voltage collapse. The GVB-8 would probably work.

A true doubler is another way to do it - but you need good 12V regulation on the turbine output (i.e. it really needs to output a solid 13.8 -14.2 volts or similar appropriate charge voltage) because all it does is double voltage. Solar Converters Inc used to make a very simple bidirectional doubler but I haven't seen it around recently.

[Sean_Ork]

...... it will output a set voltage and its MPPT tracker won't bog down the turbine or cause voltage collapse. The GVB-8 would probably work.

Just for clarity, could you confirm that you are suggesting that a MPPT charge controller (which carries out the MPPT automatically) is suitable for connection to a wind turbine ?

[Mike90250]

Some are compatible, some are not. Generally, they have a IV profile that suits PV panels. Midnight Classic has replacement IV tables for several models of turbines, But turbines have to be used with a charge controller AND a breaking system.
A simple MPPT controller, reduces load when the batteries are full. If some sort of breaking system (mechanical brakes, or electronic loading) is not applied, the turbine speeds un-loaded till it self-destructs, from bearing failure or centrifugal force. If the battery is used as the load, then the battery becomes over charged and is damaged.

[Sean_Ork]

Some are compatible, some are not. Generally, they have a IV profile that suits PV panels. Midnight Classic has replacement IV tables for several models of turbines, But turbines have to be used with a charge controller AND a breaking system.
A simple MPPT controller, reduces load when the batteries are full. If some sort of breaking system (mechanical brakes, or electronic loading) is not applied, the turbine speeds un-loaded till it self-destructs, from bearing failure or centrifugal force. If the battery is used as the load, then the battery becomes over charged and is damaged.

Indeed, that is the case - I'm pondering how jflorey2 is envisaging how that controller he suggested be configured.

[jflorey2]

Just for clarity, could you confirm that you are suggesting that a MPPT charge controller (which carries out the MPPT automatically) is suitable for connection to a wind turbine ?

Some are. The Genasun charge controller, for example, will not do any braking - so if you want to use that you either have to make sure your turbine doesn't need braking (like the Air-X) or you have a separate braking system. Also the Genasun will assume solar, and will not do as good a job tracking the output of a wind turbine.

Note that controllers that have "wind" modes, like the Midnite Classic, have separate modes with separate settings for wind; they also have an aux output that can be used to drive a brake. But they will not boost.

[tverdok]

Some are. The Genasun charge controller, for example, will not do any braking - so if you want to use that you either have to make sure your turbine doesn't need braking (like the Air-X) or you have a separate braking system. Also the Genasun will assume solar, and will not do as good a job tracking the output of a wind turbine.

Note that controllers that have "wind" modes, like the Midnite Classic, have separate modes with separate settings for wind; they also have an aux output that can be used to drive a brake. But they will not boost.

So, I could take a 24volt, 400watt three phase AC turbine that does it's own breaking and connect to Gerasun GVB-8 48volt and 48volt battery bank? And since the turbine does it's own breaking, I wouldn't need a dump load? Would be awesome if this is the case.