Micro(?) wind turbine available - general advice please

mr chips · 10-10-2020 11:04am #1

I live in the sticks and already have a ground-mounted solar array, the largest size permitted where I live in NI. I don't have a battery for storing surplus power, which was going to be the next investment, but a friend has offered me the gift of a small-ish wind turbine. He can't remember the power output - it's currently at the back of his shed, so he hasn't been able to check - but the blades are 1.5m long, so 3m diameter, and it comes with a 1500W inverter. I know this is a very generous gift - it's stuff he had acquired several years ago, with the intention of putting it up once he moved house, but plans changed and he's ended up staying put in what happens to be an unsuitable location for the turbine.

On the face of it, this is fantastic - it means I could run the entire house on renewable energy nearly 365 days a year. I'm also pretty sure I have enough space for the turbine - however, it would probably have to be right beside where the solar array is located, at the top of a slope and at least 10m from any trees/hedgerow. So I've a few questions:

Is there any reason I should the turbine further away from the panels?
What's involved in servicing a small-ish turbine like this, and how often should it be done - annually?
Would there be any specific challenges to overcome in integrating the solar array with the wind turbine? Each has its own inverter.

Any advice or observations about this are welcome - I'm not an electrician or an engineer, so will have to bring someone in to do this, but it'd be good to have a clearer idea of what's involved. There must be "unknown unknowns" which I'd rather find out about before breaking ground!

DrPhilG · 11-10-2020 9:20am

Following with interest.

I haven't yet found anything like a cost effective solution for wind generation in a domestic setting. I wish I could, as due to my location I have a consistently strong level of wind and also almost always in the same direction.

wexfordman2 · 11-10-2020 7:47pm

Siting of the turbine itsself would have to be done to avoid any shadowing I presume.

The inverter is the big question though. If you have the max solar size then I assume your solar inverter is maximum allowable as well, somadding a second diverter would most certainly make you exceed the limit allowed, I am.assumjng ?

Could you combine both wind and solar on the same inverter I wonder, bit mindful that you don't exceed the inverter limits ?

I'm no expert,.just throwing in questions to consider, hope someone else can clarify

bobbyy gee · 11-10-2020 7:57pm

Those run at about 345.watts no matter what the advertised out put you can buy them cheap on ebay

mr chips · 12-10-2020 12:27am

The solar array faces directly south, and I'm thinking of the turbine being located a few metres from its rear corner, i.e. behind it to the north-west. So there wouldn't be any issue with it casting a shadow on the panels.

I don't think I'll have to worry about routing the turbine through the existing inverter for the solar panels, as it (the turbine) comes with another 1500W inverter. That said, I'm also no expert so I don't know if I'm making assumptions about how this can all work!

When I say that the solar array is the maximum allowed, that means the maximum allowed by Northern Ireland Electricity for one tied to a single grid connection. One way around this may still be to invest in a decent-size battery when funds allow, and use that as the sole or at least primary power source for running the campsite, fed by the turbine and the panels.

In terms of power demand, I still have to finish installing the indoor kitchen (postponed in favour of the outdoor one due to Covid), which will have extractor fans plus several power points for a couple of kettles/toasters, for people to charge their devices etc. The place will also have a couple of electric hookup points for caravans/campervans, plus I'm also in the process of building a total of four timber cabins, with the first one nearly complete. Each one of those is getting low-draw lighting plus a few power sockets, and I'm also thinking of installing infra-red heaters rather than put wood-burning stoves in them. So the power consumption will definitely increase from what it has been to date.

Anybody able to give me an idea of the servicing regime for a turbine?

air · 12-10-2020 8:10am

The servicing routine generally comes down to lowering for inspection and painting or retaping the blades leading edges & changing the bearings when required.
You will need to keep an eye on it & stay vigilent for any unusual noises etc that could indicate wear or damage.
If you could post photos or other details people could advise further.
Does it have a furling tail?

It sounds like a cheap Chinese unit, the consensus for running those in Ireland seems to be to install smaller blades than they normally ship with so they are less likely to burn out from overspeedimg in high winds.

I'd also recommend installing it on a tilting polrle & just lowering it out of harms way when you know there is a storm coming.

I don't think there is any easy way for you to connect it to the grid if your PV inverter is already using your full export capacity.

kanuseeme · 12-10-2020 10:40am

Switch over at sunset and off at sunrise?

mr chips · 12-10-2020 11:24am

Cheers, so inspection to check whether bearings need replaced, and for signs of rust? No idea if the housing etc would be made of steel, aluminium or some other material. Anything else? It's not that I would necessarily try to take this on myself, but as with a car it's good to know what the maintenance schedule is, even if I'm getting a mechanic to do it.

I read recently that painting one of the blades a different colour can significantly reduce the incidence of bird strike, with purple seemingly the most effective, so I'll probably do that.

I've only one photo of the disassembled turbine & blades lying on my pal's shed floor. He says it was in full working order when he acquired it, but that he can't even remember the manufacturer or the power output! :pac:
As I said, each blade is 1.5m long so that gives some idea of the size of it.

air · 12-10-2020 1:04pm

It's a pretty typical Chinese unit, that is not a furling tail so it will overspeed in strong winds, you'll need to either lower it in strong winds and / or install a cranked arm so that the tail furls it when the wind speed is high.

There is very little to them so it's just a general visual and mechanical check that's required.

I've never heard of a bird being killed by a small wind turbine and it's very rare even with the large ones.
Think of all the birds you kill with your car in an average year, turbines are a non issue.

There is a guy in Donegal that is very knowledgeable on those turbines and has been running one for years, if you want to PM me I can put you in touch with him.

mr chips · 12-10-2020 2:06pm

Cheers, just PM'd you there. I've been looking up what a furling tail is, as it's not a term I've encountered before. I wonder how hard it would be to retro-fit something like that as part of the installation process ...

DrPhilG · 12-10-2020 3:58pm

air wrote: »

There is a guy in Donegal that is very knowledgeable on those turbines and has been running one for years, if you want to PM me I can put you in touch with him.

Send me the PM too if you don't mind. I'm also in Donegal.

unkel · 12-10-2020 4:20pm

Number of birds killed per year by wind turbines: 40,000
Number of birds killed per year by domestic cats: 4,000,000,000,000

No typo. For every single bird killed by a wind turbine, cats kill one hundred thousand of them

wexfordman2 · 12-10-2020 7:16pm

Any way we can get some renewables from cats ?

12-10-2020 7:39pm

Wasn't it the bats?
Some bright spark found that painting one blade black saved more birds. Then the turbines went outtov balance with diferential thermal expansion or something like that.

mr chips · 13-10-2020 12:47am

I remember The Oatmeal did a great strip years ago about how much cats kill. Hate seeing a neighbour's one prowling over here occasionally, as I've done a lot of tree planting and wildflower sowing over the past 10+ years to encourage more bird & bug life. A couple of times I've seen a scattering of feathers, so it's definitely hunting.

Anyway, hopefully the blades on a microturbine like this one wouldn't be significantly affected by thermal expansion. Maybe I should just paint a line down the middle of each blade ...!

13-10-2020 12:50am

Ours brings home a dead rat every week...swear to gawd!

Er..the cat...not the turbine

air · 13-10-2020 7:44am

Honestly forget about the birds, just not an issue at the high RPM that micro turbines operate at.
I've never heard anyone mention it happening.

With large turbines a bird can be flying through apparently open space when the tip of a 40m blade arrives at a few hundred kph to cut them in half.
Even so it very rarely happens.

A bird wouldn't be inclined to fly within 1.5m of a noisy turbine & the blades appear more like a disc which they will avoid.
Hundreds of rpm vs 15 perhaps!

SouthWesterly · 13-10-2020 9:22am

is the general advice to avoid the chinese ones.
If so can someone point me in the direction of a non chinese model..
I'm within sight of a wind farm so no issues with getting a gale when i need one.

thanks

air · 13-10-2020 9:38am

No, there are good Chinese ones available but you need to do your research.

Being within sight of a wind farm is no guarantee of a suitable site unfortunately.
You need a location for the turbine that has at a minimum 10x and ideally 20x the height of the turbine free from all obstructions in every direction, no trees, no buildings, nothing.

Windspot are pretty good turbines if you want to go with a European supplier.

I wouldn't contemplate a wind turbine unless I was off grid and already had 8kW+ of PV to be honest unless it was purely as a hobby interest.

mr chips · 13-10-2020 12:21pm

Yeah, for purely domestic use I wouldn't have been looking at this at all. The fact that I can get the turbine and inverter free of charge, and that from next spring I'm expecting a higher demand for electricity use in a microbusiness connected to my home, changes that picture. One of my core aims for the business is sustainability, so it's worth it to me if I can meet power demand with as little environmental impact as possible over the long term for things like outdoor safety lighting which has to stay on overnight, or for heating cabins in winter. Within the bounds of affordability, of course - last time I looked into them, those infrared heaters were fairly pricey for decent ones.

unkel · 13-10-2020 12:29pm

If you have spare renewable electricity from wind, then heating costs nothing!

You can even use a few crypto mining rigs as heaters, they will make you some real money in the meantime too

mr chips · 13-10-2020 1:03pm

It'd be nice alright to get to the point where fuel bills are zero, or at least negligible! But it's the upfront cost of the heaters I was referring to. I've already poured all my savings into the venture, so I have to cut my coat according to my cloth when it comes to what I can afford now. If I'd known about the turbine this time last year, or of course if feckin Covid hadn't happened when it did, a few things would have been done differently, or else I'd have a lot more spare cash to move things along, but shur ...:rolleyes: Next step really is to find out what the output of this turbine actually is, so I can work out what it will be capable of powering, but with travel restrictions etc I won't have it for a while yet.

Re crypto mining rigs, I ... barely know what you're talking about!

unkel · 13-10-2020 2:04pm

A 2kW heater costs not much more than a tenner. Surely that won't break the bank?

mr chips · 13-10-2020 4:54pm

Yeah, I'll have to go with something cheap & cheerful initially, but long-term I don't want to rely on convection heating as that only heats the air. In my use-case, during the coldest part of the year the cabins will likely only be occupied at weekends, and probably not even every weekend. That means that either they'd be heated up at the weekend and then allowed to cool when unoccupied, meaning that condensation and therefore mould would become an issue after a year or two, or else they'd have to be heated every day for half the year, leading to much greater running costs unless it turns out this wind turbine can provide a lot more juice than I think it can.

Infrared units will heat the infrastructure itself as well as any furniture, fittings etc, meaning condensation is never an issue. That would suit my particular needs pretty well. They also have much lower running costs if they're being left on for hours at a time, but good ones are pricey - have a look at this one that was recommended to me.
https://www.nationalheatershops.co.uk/product/herschel-summit-2600-infrared-heater/

air · 13-10-2020 8:38pm

Air tightness is the key to avoiding condensation in an empty property.
However if you've already built it, it may not be practical to improve it significantly.
A dessicant wheel based dehumidifier is most likely your best option, forget about infrared heaters for that application.

mr chips · 13-10-2020 10:30pm

The first cabin isn't quite finished, but I'm at the first fix/internal cladding stage. It will be pretty airtight (albeit with vents that can be opened & closed) and is heavily insulated, with double-glazed windows, solid timber doors & walls and 100mm of fibreglass below the roof. But if I went with a couple of fan-heaters/oil-filled radiators or similar, then when it's warm and e.g. a family of six sleep there for say two or three nights, there would be a lot of moisture in the air ready to condense once those kind of heaters are switched off. Repeat that process even just every second weekend over the colder months and I doubt I'd get away with more than a couple of years before the mould started to appear. The alternative is to keep those heaters on for all the time when nobody's there, or install infrared heating to heat the internal fabric and contents of the cabin rather than the air.

TheWonderLlama · 13-01-2021 1:10pm

wexfordman2 wrote: »

Any way we can get some renewables from cats ?

slave1 · 13-01-2021 3:39pm

unkel wrote: »

Number of birds killed per year by wind turbines: 40,000
Number of birds killed per year by domestic cats: 4,000,000,000,000

No typo. For every single bird killed by a wind turbine, cats kill one hundred thousand of them

LOL, I thought our Mammy cat (now deceased) was a fecker for birds, her daughter whom we now work for brings home one to two birds a day and uncountable amounts of pygmy screws left everywhere.
Usually just parts as she eats all the birds, we're numb to vacuuming up the feathers and feet at this stage.

Soooooo OT, apologies

air · 16-01-2021 6:35am

You could consider putting a bell on the cat, they should be mandatory in my opinion, they're one of the most destructive invasive species in the country.

Thargor · 16-01-2021 10:37am

slave1 wrote: »

LOL, I thought our Mammy cat (now deceased) was a fecker for birds, her daughter whom we now work for brings home one to two birds a day and uncountable amounts of pygmy screws left everywhere.
Usually just parts as she eats all the birds, we're numb to vacuuming up the feathers and feet at this stage.

Soooooo OT, apologies

Lol, how hilarious lol. Who gives a sh1t about biodiversity lol.

holdfast · 17-01-2021 3:57pm

I was check the interweb to see what is the cost of a turbine, got some pages not updated since circa 2012. they were the only option back then as PV was more costly. I even looked at one myself. I see a lot of them on my drives, just sitting there idle. I wonder did the O&M become too much to maintain them running ?

Can help think they are still an option for those who have the money and wish to go off grid. They can balance out the pv production with higher production at night and winter.

Thargor · 17-01-2021 10:56pm

Should be more popular now that it looks like feed in tariffs are actually on the way.

TheWonderLlama · 18-01-2021 5:51pm

I have been thinking about this and possibly utilising a hydraulic extendable mast. During day time, mast is low, turbine hidden from view behind house.
At night time, mast is extended, turbine grabs more air, charges batteries,etc, nobody can see it.

Has anyone seen this type of system? Or am i just nuts?

unkel · 18-01-2021 6:22pm

You're nuts

Anyway having a wind turbine up to a certain height (can't remember, maybe 6m?) is perfectly legal and does not require planning permission. As long as it is on your own land and if it should fall in any direction, it will have to fall within your property. This is from memory.

TheWonderLlama · 19-01-2021 4:29pm

yeah, I have been looking at the planning exemptions alright, from the SEAI site:

Turbine must not be attached to a building.
One turbine per house and it can not be sited in front of the building.
Total height must not exceed 13m.
Rotor diameter must not exceed 6m.
3m minimum clearance between ground and lowest point of blades.
Turbine mast must be the total maximum height of the assembly including turbine and blades plus one metre from the nearest party boundary.
Noise levels must not exceed 43db(A) or 5 db(A) above background noise at the nearest inhabited neighbouring dwelling.
No advertising can be placed on the turbine and the turbine must be matt finished.
The blades must not interfere with telecoms signals.

So if you have a ten metre mast with a turbine with 1m blades, then you have to have it at least 12m away from all boundaries. 10m might be high enough in any event.

I think the distance from boundary wall will catch me which is why I was thinking of the extendable thing. But i suppose if anything happened while it was extended i'd be in deep doo-doo.

ToxicPaddy · 19-01-2021 7:10pm

I've been reading up on these, but they seem more suited for houses in rural settings.

Could one of these been installed for a house in an urban setting with a small garden?

TheWonderLlama · 19-01-2021 7:55pm

I wouldn't have thought you'd get away with the distance requirements as listed above. Absolute minimum would be 5m radius all around the turbine.

(minimum height 3m, turbine blade 1m +1m)

unkel · 19-01-2021 8:32pm

ToxicPaddy wrote: »

Could one of these been installed for a house in an urban setting with a small garden?

Sure, won't generate any useful electricity though. Been there, done that. 6m pole, unobstructed incoming south westerlies from an area of mostly just fields and no buildings. Very little joy.

Markcheese · 19-01-2021 8:35pm

Could you hook up a few old storage heater ( might take a bit of looking about but they should be cheap or free ) to the turbine / panels , and try getting a really big hot water tank too ... The best place to dump electricity is into heat .,and both storage heaters and a big water tank will help balance out the peaks and troughs of power generation.... I assume during summer will be your biggest demand for hot water ,and the shoulders of the year your biggest demand for heating and hot water ..

unkel · 19-01-2021 8:44pm

Unless you live in a one off house on top of a hill in a very windy area, forget about wind. Concentrate on solar.

idc · 19-01-2021 9:11pm

unkel wrote: »

Sure, won't generate any useful electricity though. Been there, done that. 6m pole, unobstructed incoming south westerlies from an area of mostly just fields and no buildings. Very little joy.

How many watts did it generate at low speed? I'd still consider getting turbine if at low speed it produced 100-200 watts to cover base load. Maybe what i want is unrealistic though!!!!

unkel · 19-01-2021 9:14pm

It's unrealistic. You get almost nothing in an urban setting, unless the wind strength is just right (strong steady wind, but not a storm). Even at that, perfect conditions that you will rarely see, maybe a few hours a month, you won't even see the rated power output. Honestly take my word for it, don't do it. Go solar.

DrPhilG · 19-01-2021 11:25pm

unkel wrote: »

Unless you live in a one off house on top of a hill in a very windy area

I'm not far off that description...

graememk · 19-01-2021 11:27pm

Attached is a pic from on top of a roof about 7-8 m high.

A turbine here might just be viable in this scenario, but compared to solar, and the payback of that, its no competition. - Id be better off sticking more solar on the roof.

mr chips · 19-01-2021 11:30pm

Have to agree - as the OP, the only reason I was even considering this was because the turbine will be coming to me as a gift, whenever I can consider doing a long distance trip to actually get the thing. Even then, while I live in a rural setting and can potentially place the turbine at the top of a slope, it might still be more trouble than it's worth as it will be difficult to find the space for it in the campsite. I'd far rather just have a battery and one or two more pairs of panels. I'm actually toying with a plan B involving donating it to a friend who lives in a similar setting in NI, only with double the space which (unlike mine) is not set to be used or occupied at all, and then just splitting any FIT proceeds between us.

mp3guy · 20-01-2021 11:59am

graememk wrote: »

Attached is a pic from on top of a roof about 7-8 m high.

A turbine here might just be viable in this scenario, but compared to solar, and the payback of that, its no competition. - Id be better off sticking more solar on the roof.

Not necessarily. You're looking at about €25k for a 3kW turbine that'll last. If you have decent mean annual wind speed (8 m/s), you'll generate close to 12MWh per year. Price a similarly sized solar PV array, it probably isn't too different.

air · 20-01-2021 1:01pm

A 12kW PV install (to generate that 12MWh ballpark) could be done DIY for €7k pretty easily I would think.
There's a lot of space between that and €25k.

Small wind makes no economic sense unless off grid (even then a generator along with an oversized PV array is likely cheaper).

mp3guy · 20-01-2021 1:03pm

air wrote: »

A 12kW PV install (to generate that 12MWh ballpark) could be done DIY for €7k pretty easily I would think.
There's a lot of space between that and €25k.

Small wind makes no economic sense unless off grid (even then a generator along with an oversized PV array is likely cheaper).

Would love to see the breakdown for this, including inverters that can work with such an array *and* limit export to 6kW which is required for domestic installs, where a 3kW turbine wouldn't have this problem.

Additionally, if you wanted to emulate the smoother continuous supply from a turbine, you would need batteries to accomplish that with solar PV, so if you want to price apples to apples, you need to include that.

air · 20-01-2021 1:31pm

Limiting export is simple, simply install a 6kW inverter and over supply it with the 12kW of PV, job done.
Smooth continuous power is pretty irrelevant and in any case PV tends to be a lot smoother than wind.
I helped a friend install a 5kW ground mount array last year for far less per kW than I have quoted but that was with exceptionally cheap panels which was why I increased my estimate to the 7k figure.
This is more than generous taking current retail pricing into account.

Edit - had a look on solartricity, 12kW of panels €4k, 6kW inverter €800
Leaves plenty in the €7k estimate for a mounting system, cable, isolators, ducting etc.
Obviously buying 2 pallets of panels opens up the possibility of better pricing on those also.

mp3guy · 20-01-2021 1:41pm

air wrote: »

Limiting export is simple, simply install a 6kW inverter and over supply it with the 12kW of PV, job done.
Smooth continuous power is pretty irrelevant and in any case PV tends to be a lot smoother than wind.
I helped a friend install a 5kW ground mount array last year for far less per kW than I have quoted but that was with exceptionally cheap panels which was why I increased my estimate to the 7k figure.
This is more than generous taking current retail pricing into account.

Can't say I agree.

air · 20-01-2021 1:52pm

mp3guy wrote: »

Can't say I agree.

Well it's hard to argue with such a considered and verifiable contribution to the thread.

Micro(?) wind turbine available - general advice please

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