Adding wind turbine to PV array

maric

Just found this forum we're completely off grid and running on solar power, it's a 48v system which is great during the summer (we're in southern Spain), but not so great in the winter as there's little sun and a LOT of wind. I was thinking about adding a wind turbine to the system, as the prices are so low now. We have a hybrid MPPT inverter charger but from what I've read on this forum so far, I need a separate charge controller connected to the battery bank for the turbine? If so, would pwm be OK next to a mppt? In our climate the sun and wind are quite separate so they shouldn't clash much. To give a bit more info, we typically get around 800w from the solar array and the turbine I'm looking at is also 800w max power. Thanks in advance

Photowhit

I don't think there would be a problem with the 2 charge controllers on 1 battery bank. 
I don't believe we have a strong person on wind who regularly participates currently.
If you search our past threads we had a guy named Chris Olsen(?) who was very strong on wind and you might find some good advice.

In general small wind is difficult, it requires more maintenance and also requires a dump load, usually a heater of some sort water or air since while spinning they will produce power that needs to go somewhere. Unlike solar which can just be turned off. If you are in a windy area it can work nicely.

BB.

Just out of curiosity, where in Spain... For example, looking up Valencia and Marbella Spain, fixed array:

http://www.solarelectricityhandbook.com/solar-irradiance.html

Valencia
Average Solar Insolation figures

Measured in kWh/m2/day onto a solar panel set at a 50° angle:
(For best year-round performance)

Jan	Feb	Mar	Apr	May	Jun
3.95	4.47	5.29	5.63	5.58	5.90
Jul	Aug	Sep	Oct	Nov	Dec
6.29	6.09	5.38	4.62	3.76	3.38

Marbella
Average Solar Insolation figures

Measured in kWh/m2/day onto a solar panel set at a 54° angle:
(For best year-round performance)

Jan	Feb	Mar	Apr	May	Jun
3.49	4.16	5.28	5.67	5.86	6.54
Jul	Aug	Sep	Oct	Nov	Dec
6.90	6.75	5.88	4.49	3.54	3.03

Even in December, 3 hours of sun per day is not bad...

If you were to add 800-1,600 Watts of solar panels--How would that compare to the cost for adding wind power (typically, the tower and support hardware costs way more than the turbine itself--Add the need to service that turbine every 1 year or so--rent truck, or setup a tilt tower). Towers should be (typically) >=10 meter tall (33 feet) and above nearby trees/homes (30 meter towers are closer to ideal--But hard to justify costs).

If you are not a do it yourself type person (winch, tractor, boom truck), the support issues/costs are not trivial.

Has anyone installed a wind system near you? Can you get their monthly energy production numbers for 1+ year period? Most small turbine installations produce very little energy over time, and seem to fail/fall into disuse after a year to two.

I am not a big fan of wind...

-Bill

Dave Angelini

I do have alot of previous experience with wind gens and very few people ever have the talent for the maintenance of going up high on a tower where useful energy is. 

The same with roofs for solar offgrid.

Not a Fan as you say Bill.

706jim

One thing seldom mentioned with small wind generators is their probable output over time. Those showing, say, 400 watts can only do that with 40mph wind speed which is not that common. And then only when airflow is unobstructed as when the turbine is quite high up. Output at a more realistic 15-20 mph is a LOT less. Plus anything mechanical is prone to wear, corrosion and vibration. I'd get more solar. Also just noticed Dave's comments about solar on roofs. Just had mine re shingled and the panels are now ground mounted.

BB.

I will post one link here to a 10 year old article about some open field tests of lots of (then current) small wind turbines:

http://forum.solar-electric.com/discussion/3638/small-windpower-a-scam-survey-says-so/p1

If you want more links, look at this post here (from our FAQ like page):

http://forum.solar-electric.com/discussion/comment/77299#Comment_77299

Links to both positive and negative information about wind...

-Bill

BB.

Here is some data from a relatively good size Skystream in a windy lakeside location (Lake Erie)...

Note no original link available... Had to recover from copy on forum. These are kWH per month numbers:

	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP	OCT	NOV	DEC	Total
2007	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	175	225	0*	400
2008	98*	292	308	246	228	153	92	84	97	164	246	472	2,480
2009	265	348	244	371	182	86	90	84	250	100	194	131*	2,345
2010	101	130

* December, 2007 - Skystream shut down from software problem with cold and would not restart.

* January, 2008 - Skystream down until the 27th. Produce 98kWh in the 5 days remaining in the month.

* December, 2009 - Skystream shut down several times and would not restart on it's own, production very low for wind speeds.

* January, 2010 - Production very low for wind speeds.

* February, 2010 - Production very low for wind speeds.

Skystreams seem to miss the "reliability" target... But when they worked, they did harvest pretty well.

This is about the only "Long Term" data I have ever found for a small wind turbine installation... I just do not ever see/find any other data from any other source that even near 1-2+ years in length.

-Bill