Setting up a very small turbine to the grid

[Mudsloth]

I have decided to document the installation of my wind turbine so for those of you who want to go through the precess may know what to expect.

Well, i bought a small (300w) wind turbine with the intention of putting it on my block in Beaufort and connecting it to the grid. I bought a small one as this is the first time I will be grid connecting a turbine and if all goes well I will be setting up a few larger, 2kw, turbines in the future. So far I have contacted the council and have been told I do not need a building permit but may need a planning permit as there are no permanent structures on the property. I am waiting for them to investigate this and decide.

Turbine stats:
3 phase 24 volt 12.5 amps.
3 blades 1.16m dia
cut in wind speed 3.5m/s
Over speed protection is provided by tips stall, passive turned and electric brake.

I havn't made a firm decision on the inverter yet but will prob have to go with a 3 phase Chinese one as the voltage is so low. There is an American made 3 phase I am looking at as well. Both are Iso, rohs and CE certified, will keep you posted on this.

I will be using quarter inch pipe and guy wires to mount this one, 12m pipe in 1.5m of concrete and 6 guy wires. Prob overkill but better safe than sorry.
Anyway, i will provide pics as things progress but this will prob be a long winded (get it) exercise so stay tuned!

[bee utey]

At 300W just rectify it with a diode set from an old car alternator and feed it straight to a small solar grid inverter. Some of these sell on ebay for as little as $100.

[Mudsloth]

At 300W just rectify it with a diode set from an old car alternator and feed it straight to a small solar grid inverter. Some of these sell on ebay for as little as $100.

It has to pass two electrical inspections before it's legal. I'll ask but I don't think powercor will be happy about it.

[Warb]

Just a thought, but before you spend money connecting it to the grid you might just run it for a while and see whether it works. A 300W turbine wont produce much power at the best of times, and will take an age to pay back it's investment - the grid metering alone is likely to cost $200-$400.

Most people's experience is that wind power is a nice idea but useful only for topping up a few batteries.

The start-up speed of 3.5m/s is 12kph, and you need an average of more like 20kph, and that average can't include big gusts. There aren't many places that have that kind of average wind speed.

Forgive me if you've already crunched the numbers and measured your average windspeed over a year, but most people don't bother. I've seen a few people now who've spent big bucks on wind turbines (300W up to 2kW) and been very disappointed.....

I now tell everbody to buy a cheap weather station, mount it on a pole and then see what the average windspeed is after a few months. Almost everybody, even those who thought they lived in a windy area, find their average windspeed is far too low to usefully drive a turbine.

Of course if you live on a sea cliff, or right on the edge of an escarpment where the wind blows constantly all the time, then wind power will be great!

Edit: In NSW, CE approval and suchlike is meaningless. Anything connecting to the grid needs to be on the CEC (Clean Energy Council) approved list, or they wont allow it. I'm not sure if this applies in other states but it's worth checking before you buy!

[rovercare]

Just put solar up, atleast it will work:D

[bee utey]

Just put solar up, at least it will work:D

Absolutely! Once your solar system is up and legally connected, you can plug in one of those cheapie inverters and no-one will notice. It will possibly add 5 - 10% (optimistically) to your daily output of a 1.5kW solar system. It may pay for itself in a decade or two...

Actually, throwing your camping solar panels on the shed roof while you are home will be a simpler outcome, that way you only need the inverter and you may indeed pay it off before it blows itself up. The smaller inverters work from 14-28V input so are well suited to a maximum power output voltage of around 17V.

BTW a friend of ours at Mt Compass SA had an off grid house with wind and solar. Whenever we went to visit him the wind generator would have lost another blade as he was out while the storm hit. Regardless of their level of self-protection, a decent storm will smash one without adding anything to the regular output.

[Mudsloth]

Just a thought, but before you spend money connecting it to the grid you might just run it for a while and see whether it works. A 300W turbine wont produce much power at the best of times, and will take an age to pay back it's investment - the grid metering alone is likely to cost $200-$400.

Most people's experience is that wind power is a nice idea but useful only for topping up a few batteries.

The start-up speed of 3.5m/s is 12kph, and you need an average of more like 20kph, and that average can't include big gusts. There aren't many places that have that kind of average wind speed.

Forgive me if you've already crunched the numbers and measured your average windspeed over a year, but most people don't bother. I've seen a few people now who've spent big bucks on wind turbines (300W up to 2kW) and been very disappointed.....

I now tell everbody to buy a cheap weather station, mount it on a pole and then see what the average windspeed is after a few months. Almost everybody, even those who thought they lived in a windy area, find their average windspeed is far too low to usefully drive a turbine.

Of course if you live on a sea cliff, or right on the edge of an escarpment where the wind blows constantly all the time, then wind power will be great!

Edit: In NSW, CE approval and suchlike is meaningless. Anything connecting to the grid needs to be on the CEC (Clean Energy Council) approved list, or they wont allow it. I'm not sure if this applies in other states but it's worth checking before you buy!

The area i'm putting it in has plenty of wind to keep her spinning, I've studied this since we bought the property a couple of years ago. Especially helpful was access to the neighbors 2kw turbine that goes quite well pretty much all the time. the total investment will be around a grand, the smart meter was installed a few months ago for the solar systems that are going up there as well. I realise the power output won't save the world but from what I have observed I estimate that it will spin at around 70% capacity, 24 hours a day (average) over the course of the year, this will destroy what the solar panels could ever do. Also the reason I chose a small cheap one to start was to become familiar with the whole process, particularly the lagal side of things before putting bigger ones up. I neglected to write that all equipment I'm planning on using is cec certified.
Cheers for the comment though, keep them coming, it's a bit hard to find sounding boards amongst my friends as good as the ones here. My mates just nod and look at me like I'm mad:D

[Mudsloth]

Absolutely! Once your solar system is up and legally connected, you can plug in one of those cheapie inverters and no-one will notice. It will possibly add 5 - 10% (optimistically) to your daily output of a 1.5kW solar system. It may pay for itself in a decade or two...

Actually, throwing your camping solar panels on the shed roof while you are home will be a simpler outcome, that way you only need the inverter and you may indeed pay it off before it blows itself up. The smaller inverters work from 14-28V input so are well suited to a maximum power output voltage of around 17V.

BTW a friend of ours at Mt Compass SA had an off grid house with wind and solar. Whenever we went to visit him the wind generator would have lost another blade as he was out while the storm hit. Regardless of their level of self-protection, a decent storm will smash one without adding anything to the regular output.

At home I have around 4kw of panels and a 600w wind turbine. Your idea about the rectifier actually got me thinking about the turbine at home that charges 2 banks of batteries which are configured as 12 volt each. I've set the battery banks up as a 12 volt as the turbine will normally put out 14 to 20 volts with the amount of wind we have here most days (pascovale south). The problem was I have to go out and hook the batteries up as 24 volt when I want to drain them into the grid, not a major problem but a pain none the less. So I jumped onto ebay and bought a 12v to 24v step up converter. 24 volts at 10 amps matches the 300w grid tie i'm gonna use pretty well. I'll set the charge controller to release power at 14 volts. We'll see if it works, i'll let you know. I'm sorry to hear about your mates blades breaking. The turbine i have at home has survived a couple of nights of 90k winds and the little guy i'm putting up is rated to 162kmh so i'm not worried about any of that. See what i mean about sounding boards? God I'm glad I didn't buy a Toyota.........:D

[Warb]

......but from what I have observed I estimate that it will spin at around 70% capacity, 24 hours a day (average) over the course of the year, this will destroy what the solar panels could ever do.

70% of generation capacity, given an average small turbine with a rated power output at 15m/s (which is about standard) equates to an average windspeed of perhaps 12m/s - over 40kmh....... the start-up windspeed is the point were the rotors actually move, the cut-in speed is where power is produced and the power curve is close to exponential, so generally speaking;

50% rated windspeed = 2.5x start-up windspeed = 20% rated output

If your 70% estimate is realised, I'd be on the phone to the relevant companies offering to sell them the land! As I said above, even the sellers of commercial wind farms don't quote numbers above 35%, and international reality drags that down to 20% or less. Seriously, if the wind where you are blows at above 35kph for more than 70% of the time I wouldn't bother building a house there, it will be a commercial wind farm before very long!!!

We've always regarded our farm as being "windy", so when I started contemplating renewable energy I looked at wind turbines. I had put up a semi-professional weather station a few years earlier (we need the data to schedule irrigation) so I looked at the wind speeds. Remembering that we consider the place to be windy, based on perceptions, how surprised was I to discover our average wind speed was only about 2m/s. That's below start-up for most turbines, greatly below the generation cut-in, and nothing compared to the 10-15m/s required to even approach rated output. Then I considered that at 50% of rated wind speed most turbines produce only about 20% of their rated output, and I realised I was on a hiding to nothing! I looked at a 400W turbine that the manufacturer claimed would produce 38kwh per month with an average of 12mph (19kmh) winds. That's over 5m/s, which is more than twice my average, and equates to only 13% of the units rated output. And that's their marketing blurb!

I installed PV in the end, and over nearly two years I've seen about 19% efficiency (i.e. each 1kw of panels generates about 4.5kwh/day on average).

[Mudsloth]

The average wind speed in beaufort this year has been 5.5m/s at a height of 2 meters. The turbine is going to be approx 10 meters, more likely 12m above the ground. I'm taking my 70% measurement from what the neighbors have been getting and yes that may be optimistic but I don't think so. The property is quite elevated, close to a very large lake and along the same lines the big turbines are placed. I'm confident the wind speeds at 10 meters will be sufficient to drive it. On seemingly still days you can still fly a kite so i'm very sure there are some nice currents to be tapped into. Anyhoo, time will tell and damn it it all I love wind turbines! I'll post again when i've heard back from the council and I'm ready to put in concrete.

[Warb]

OK, if your neighbours 2kw unit has made over 12,000kwh per year then I retract all my negativity and advise you to go out and buy as much turbine capacity as you possibility can!

If the average windspeed at 2m is 5.5m/s, at 12m it will be:

(5.5 / 1.1) * 1.425 = 7.1m/s

This is indeed very high (Ballarat - I'm guessing you're in Victoria? - is only about 3.8m/s and Crookwell is 4.2m/s), but even so the predicted capacity factor is only about 42%.

Let me know how you get on.

[PhilipA]

Just to add, denmark which is reputed to be the winiest placein teh world and has several offshore fields such a Mittelgrunden has the following according to Wikipaedia.


In 2005, Denmark had installed wind capacity of 3,127 MW, which produced 23,810 TJ (http://en.wikipedia.org/wiki/Terajoule) (6.6 TW·h (http://en.wikipedia.org/wiki/TW%C2%B7h)) of energy, giving an actual average production of 755 MW at a capacity factor (http://en.wikipedia.org/wiki/Capacity_factor) of 24%.[1] (http://en.wikipedia.org/wiki/Wind_power_in_Denmark#cite_note-DK-0) In 2009, Denmark's capacity grew to 3,482 MW; most of the increase came from the 209 MW Horns Rev 2 (http://en.wikipedia.org/wiki/Horns_Rev_2) offshore wind farm, which was inaugurated on September 17, 2009 by Crown Prince Frederik (http://en.wikipedia.org/wiki/Frederik,_Crown_Prince_of_Denmark).[14] (http://en.wikipedia.org/wiki/Wind_power_in_Denmark#cite_note-13) the end of 2010[update] (http://en.wikipedia.org/w/index.php'title=Wind_power_in_Denmark&action=edit), Denmark's capacity stands at 3,752 MW; most of the year's increase came from the Rødsand-2 (http://en.wikipedia.org/wiki/R%C3%B8dsand_II) off-shore wind farm.[15] (http://en.wikipedia.org/wiki/Wind_power_in_Denmark#cite_note-Stamdataregister-14)

This accords with figures from the Mittelgrunden site indicating around the same % down to about 12% in July.
Regards Philip A

[Mudsloth]

I love the negativity, it makes me feel warm and fuzzy. According to willyweather.com.au the average wind speed in Beaufort at 2m above the ground this year is 5.5ms. The neighbors wind turbine is their only source of power and they use a bar heater as the load dump. One thing i've learn't from buggerizing around with my wind turbine is the numbers offered up in general mean not much. Something funny I just found out, the guy who first came up with the system for measuring wind speed was named Beaufort. I don't know what terrain you guys live in or how much practical experience you have with turbines but Beaufort is smack bang in the middle of amazing prevailing winds all year round, could be why their are plans for a 200mw wind farm there. Anyway fellas, jump and down all you like but I am positive this little turbine will put out 3.36kw per 24hrs minimum and I'm quietly confident it will almost triple that ON AVERAGE over 12 months. I do however reserve the right to fit 5 blades instead of the standard 3.

[Mudsloth]

One more thing, keep the robust debate going, as far as i'm concerned this thread is great just because of the step up thing I bought! Thanks bee utey!

[bee utey]

My wife grew up in Warrnambool. She knows about continuous wind. That's why she moved away, it drove her nuts!

Enjoy your wind, it sounds like a valuable resource.:)

[Warb]

Do you realise that there is no weather station in Beaufort, and willyweather looks to be reporting the numbers for Ballarat airport?

Anyway, assuming that you have the same wind conditions as whatever willyweather is showing, I'd knock the average down a bit because it looks like you have a fair amount of high wind (which isn't useful to a turbine). Having said that, if you manage to average 7m/s at turbine height of 12m (which is about 5.5m/s at 2m height) conventional wisdom suggests you'd make about 3kwh/day on average. Which is about 43% capacity factor and way better than any commercial wind farm I've heard of.

The dump load doesn't really relate to anything except the capacity of the turbine - you always need a dump bigger than anything the generator can throw at it under maximum generation. When their batteries are 100% full and they have no usage, all the power from the turbine goes to the dump so it has to be big enough to cope.

If you've got all that wind you should do well... but not a 70% capacity factor!

[superquag]

It should be possible to do both..

We've lashed out on a 3.76 kW system, 16 panels (in 2 strings of 8), feeding in to a 3-input, 4.6kW inverter.

This leaves us the option of upgrading with another string, or, a wind-generator of some kind.

Some real-life figures for comparison.

Our metal roof is pitched at 18 degrees and faces exactly NE, which gives us best production early in the morning. By 3 pm the output is dropping fast and after 4pm is pretty dead. By contrast, the system is awake at 6 ~ 6:30 AM.

Last Friday was a good day... 900 watts at 6:30AM and 3195 Watts at midday, producing 14 kW/hs in that time-slot. We exported 10, bought in zero.

Previous day it generated 25 units, importing ONE unit and exporting 18. - That was from 6:30AM to 6:00pm

Yesterday over here was overcast and rainy, and we bought 5 units and sold 1. Total day's production was 6 units.

The original plan was to put up a 3rd string when finances (or insanity) permit. Or Wife...

Since the current setup easliy reaches 3kW under good conditions, and I've seen in excess of 4kW, the new string would have to be N or NE facing.
However, we do get the morning 'Gully Winds' in the warmer months, and they can go for 4 ~ 6 hours consistantly... which makes this thread rather interesting !:p

[slug_burner]

These guys (http://www.otherpower.com/20page1.html) made their own turbine. I like the DIY approach to keep the costs down, I don't know if they are anywhere near the potential efficiency for a big set of blades like theirs coupled to their home made alternator.

[rovercare]

How do you find a sparky nice enough to sign it off?, I'd be sure charging a substantial premium!