DIY wind turbine

BrenCooney

anybody have experience of buliding a Hugh Piggot style wind turbine and if so did they grid tie it, or run it via batteries.
was talking to somebody recently and and he stated that he had heard that the self build had a problem being grid tied directly. ie should go through a battery bank.

i have gone through the maths using SEI data and the calcs from a dutch wind site and my site appears to be okay. living in the sounteast with the sea 300 metres from the house and nothing but shallow sand dunes in between

Brenc

bladespin

Shouldn't be a problem to grid-tie one you'll just need a suitable inverter.

quentingargan

You would just need to wind the generator for higher voltages than would normally be used for a battery system. Inverters can take anything between about 50V and 600V, but you would need the inverter to be able to work well over the range of generator speeds being produced, so when the genny is maxed out, it should be close to 500V, rather than 56V for a battery system

pirateireland

My old man, a spark by trade, set up a home energy system on the family home. The first thing he got was a 1kw turbine. (Pm for company name)

It's on a 40ft-ish pole bolted to the garage, charges an old 400ampere hour battery that in turn runs through an inverter to power a small separate grid.

Our lights, tvs, computers, circulating pumps and select sockets all run off this home grid. When the battery reaches a certain low, all power flicks over to the ESB power. It is possible to have both a home grid and ESB grid power same house and mixed appliances, you'd want to recruit a spark.

Over time he added PhotoVoltaic panels, and flat panel water heaters to the roof. The PVs also charge battery, where as the flat panels heat water of course...

You being 300m from the sea with no obstruction would be insane not to set up a similar system :rolleyes:

Best results are from a turbine with no land/building obstruction in 360 degrees. And the higher you get it the better the wind. I don't have the data to hand, but Ireland has the best wind available to it in all of Europe. And yet Holland and Germany have more windmills!!

Hugh Piggott is my oul fellas idol!

quentingargan

A battery has a round-trip efficiency of 80% in ideal conditions, but in a wind system it is often closer to 60%. Also, in the system you describe, unless the wind blows fairly soon, the battery is going to sit there in a low charge state for quite a while before getting topped up. Many deep cycle batteries don't like that sort of thing.

Under these conditions after 500 cycles, the battery is finished. Lets take a 165 Ah deep cycle battery. You will do well to get one for €75.

It stores 1.98 KwHrs of power, and 500 cycles would be 990 Kw Hrs of storage in its lifetime. €75 for 990 KwHrs means that storage cost you 7.5c per KwHr.

You also lost, lets say, 30% of the power. So assuming a retail price of 14c, that cost you a further €41.78, or 4.2c per Kw hr.

The final rub - if you had sold that power to the ESB, you would have got 19c for it, not 14c. That's what they are paying at the moment.

I have a battery system myself, and I put it in at a time when we had no notion that the ESB would EVER buy back our power. It doesn't make economical sense anymore though to my mind. If you take an apocalyptic world view and believe there will be wholesale power cuts, that is another matter. And sustainability is often a hobby rather than an economic pursuit.

But professional systems these days are grid tied for many reasons - it is a lot less troublesome.

para45

I think its better to grid tie and not mess around with batteries becuase what you put in you can take out so they might owe you all the time and just subtrack it from your esb bill and you might never owe them again as they might owe you .

I was speaking to a architect the other day and he said people with a big Kw Turbine should install storage heaters so that you wont have to be dependant on Gas or oil:)

quentingargan

para45 wrote: »

I was speaking to a architect the other day and he said people with a big Kw Turbine should install storage heaters so that you wont have to be dependant on Gas or oil:)

That would be a fairly apocalyptic world view. Storage heaters can be charged using off-peak electricity at just 7c per watt. Why would you use your turbine to do this when it could be exporting power to the ESB at a higher price, and possibly at a time of year when you don't really need the heat anyhow.

Electricity is a very valuable energy source. It takes over 2.7Kw or oil or gas to make 1kw of electrcity. Turning that electricity back to heat is quite wasteful. If you want to see it put to good use, buy an electrc car. Now your KwHrs of electricity are saving a lot more oil:)

para45

Becuase when you swopping electricity credits on a month to month basis you not making a gain where as idf you are actually making money from it you start to have tax implecations when you are a high earner so its starts to cost you . Burn as much of your own electricity as you can .

bladespin

para45 wrote: »

Becuase when you swopping electricity credits on a month to month basis you not making a gain where as idf you are actually making money from it you start to have tax implecations when you are a high earner so its starts to cost you . Burn as much of your own electricity as you can .

TBH to get to the point where I'd be concerned about the tax implications of my turbine I'd have to in the be installing something 20kw+ range (far beyond anything a DIY enthusiast would put together), with prices for these monoliths starting around the €50k mark I doubt many will be affected.;)

The ESB credit is calculated on a yearly basis.

para45

ye my house is on the coast . The last few dayds force 6 wind do the maths 5kw turbine with constant wind and self assesment is also once a year.

I didnt state to make the oil burner obsolete but adding storage heaters to a house with oil heating can help and will reduce your oil bill when there is constant wind etc

maybe I am wrong !!!!!

bladespin

para45 wrote: »

ye my house is on the coast . The last few dayds force 6 wind do the maths 5kw turbine with constant wind and self assesment is also once a year.

I didnt state to make the oil burner obsolete but adding storage heaters to a house with oil heating can help and will reduce your oil bill when there is constant wind etc

maybe I am wrong !!!!!

Even coastal sites wouldn't make the kind of return that would have me running from the tax man:

The best coastal sites I've seen have average windspeeds of about 8m.sec at the hub so calculating that out over a year would give you something like this:

Units generated: 15000 (assuming a well maintained 6kw)
Units used: 5500 (on average)
Units sold: 9500

The ESB will buy these at 9c per unit : €855
SEI will pay a bonus of 10c for the first 3000 of these too: €300
That should equate to a credit of €1155 with the ESB, not a payment as yet AFIK, can the revenue tax electricity credits?

Bear in mind, most 6kw machines need an annual service, you should be allowed to deduct that anyway.

TBH if you have a 6kw the most sensible thing to do is use the power, you'll be saving 16.5c as opposed to earning 9c. They don't make financial sense otherwise, on the likes of dairy farms and in workshops they pay for themselves but on a household I don't think they would ever make a return on investement.

para45

Ye the revenue taxes everything that you earn . WIll have to look into the credits as per our Goverments link to the greens they must have some deal to the tax re people trying the best to have a green lifestyle. Maybe there is a tax credit or up to a amount that you can earn generated by windpower will be interesting .

Ye I know this link is for small wind turbines home hobby etc .Thats what it is also for me with the view to get a 6kw one in the future

I need to get back to you all as A mate down the road has been measuring the wind speeds and came up with some mad data . He did his sums also and it was amazing what he would generate with even a small turbine sticking to proper formulas and not pie in the sky type turbines but trusted proven ones

morning delight

Folks

Is there much of an issue with siting the turbine ~400m away from the dwelling? What cabling would be involved and would it lose much power over the distance?

The turbine and house are both located on the same farm so there aren't any issues with landowners etc.

quentingargan

morning delight wrote: »

Folks

Is there much of an issue with siting the turbine ~400m away from the dwelling? What cabling would be involved and would it lose much power over the distance?

The turbine and house are both located on the same farm so there aren't any issues with landowners etc.

Assuming that the voltage produced by the turbine is high enough, that distance shouldn't be a problem.

Say you have a turbine producing 3kw at 350 volts 3 phase, using 3X10mm armoured cable would give losses of about 2%. If you halve the voltage, you would have to quadruple the cable size. So check the voltage of the system.

I use an online calculator which I can't find now, but have as an excel spreadsheet. I can email that to you if you pm me.

I made the mistake of getting a 2.5kw 24V battery turbine system a few years back. For a distance of 70m from the house, I had to use a 3X70mm cable to get losses down to 10%!

Q

del88

Here's some motivation..

morning delight

quentingargan wrote: »

Say you have a turbine producing 3kw at 350 volts 3 phase, using 3X10mm armoured cable would give losses of about 2%. Q

I've just had a quick google of armoured cable and it doesn't come cheap! A 100m roll of 10mm costs £240 ex vat. Now multiply that by 12 (for 400m length).... add vat... convert to euro...

quentingargan

morning delight wrote: »

I've just had a quick google of armoured cable and it doesn't come cheap! A 100m roll of 10mm costs £240 ex vat. Now multiply that by 12 (for 400m length).... add vat... convert to euro...

Not quite that bad. When I say 3X10mm, I mean 3 strands of 10mm wire, usually in one armoured cable. Armoured comes in 3X10mm or 4X10mm. So you only need four rolls. Still €960.

You can't really go above 350V AC. When rectified, this will come up to about 470V DC, which is close enough for comfort to the 550 to 600V that would blow most inverters. If you wanted to go any higher, you would need a transformer back at the house... Q

morning delight

quentingargan wrote: »

Not quite that bad. When I say 3X10mm, I mean 3 strands of 10mm wire, usually in one armoured cable. Armoured comes in 3X10mm or 4X10mm. So you only need four rolls. Still €960.

You can't really go above 350V AC. When rectified, this will come up to about 470V DC, which is close enough for comfort to the 550 to 600V that would blow most inverters. If you wanted to go any higher, you would need a transformer back at the house... Q

That's not so bad for the advantages gained: better site and further away from the house.