Thread: A real wind generator. Country situation. Need power!

Here is the deal, we are looking at a couple pieces of land in the country where the "rural" electric providers operate. They apparently LOVE to screw people. Probably $50-100K for a decent 3ph service. I have looked at wind generation before and planned to supplement the place with it. However, given the price of the friggin power company, I am curious what options are available?

Here is the deal, I plan to build my own head unit and upright. Already talked to the county and they will be fine with it as long as we put the engineering stamp on it. No biggy. I plan to make the props but would need to buy the generator portion. Not sure what to use there.

This brings me to distribution and storage of power. I have NO IDEA what will work best for this. I know lots of small units just use a 12V battery and an AC converter but this will end up being A LOT of batteries. I really would like to store power if possible though because I cannot rely on the wind here even though it blows A LOT around here. Thus the reason for the power company building a HUGE wind plant 30miles from here.

I have not done any power numbers yet but I think 100KVA will be a target or close to. I can build a 20ft diameter prop in one piece or build separate pieces if I need bigger. I realize I could need more than one generator to do this.

Ideas for parts and power storage?

100 KVA is 80 KW.
A 12' diameter small commercially made unit, which costs $10,000 or more and makes 2.4KW.

I am guessing to get 100KVA, with a battery bank, control system, and a row of towers and generators, that $50k to $100k from the utility is gonna look like a steal.

Most people I know who are in similar situations go with a diesel generator to provide 3 phase, and smaller, cheaper, solar/wind combos to run 12 volt power for lights, along with using propane fridges.

Wind aint cheap.

What does the utility charge to bring in single phase
residential power?

You can always go the phase converter route.

Jim

That is a part that torques me Jim, the power company will not allow anything bigger than a 10HP load on a single phase. They also offered a "V phase" which is 2 phases that are running down the road and I guess they can build 3ph out of it????? Did not know that was possible but they can only offer 100A on that and will still cost a bunch.


We will have to have an engineering meeting on the subject but my thought was to bring power straight into the building via 3ph and regulate the unused into a battery bank of some sort so as to create a storage cell and have that tied right back into the grid so as the wind system goes down, the battery system is already running and will just take over seemlessly.


Again, I have not done too many numbers yet and I realize that cost/labor may not pay off but I see it as a challenge and if I can make enough power, I will run mostly electric in the whole shop for everything. I realize there are plenty of residential type heads out there but we are looking to build a real head from scratch with a PLC system, articulating head, and auto adjust pitching. Been talking about it for years. We have an average of 15mph wind speed here but see frequent days well over 40mph.

Originally Posted by viper

..... We have an average of 15mph wind speed here but see frequent days well over 40mph.

I have a book called "Wind Power Workshop" that has a table for average power output for different blade diameters and average windspeed; 12' diameter at 13 mph produces just under 500 watts. The output depends on the square of the windspeed and the area of the blade diameter so for 15 mph and 20' diameter I guess you could expect a bit less than 2000 watts. These figures use an efficiency of 15% for the windmill.

Viper;

I was in the windmill business for about 20 years. I think I'd rather take a stick in the eye than what you are proposing.

Craig Donges

OK....


There is a lot more to wind generation output than the diameter of length of the rotor blades. We are also not governed to 20ft either. That would just be easiest.

Here is my help on this. I'm an Electrician and I specialize in industrial power systems and remote power systems. I'm currently building a 200 kW system in the mountains of British Columbia to power a heli ski lodge.

It all depends on what type of loads you want to run. If you want to run resistive loads - alternative power is not a good option. If you want to run motor loads even more so. Alternative power sources are best for light loads and for loads that do not run that long or have deep draws.

The problem comes with storage capacity. When you have loads that require a lot of current you need to store that power somewhere (i.e. batteries) and those get: large, heavy, expensive to buy and maintain. Because building a prime mover / generator that is large enough to continuously generate enough capacity to power your loads is expensive and not usually a great option.

It is much cheaper to design a system that can power 20% of your loads 80% of the time and 80% of your loads 20% of the time then something that needs to power your loads 100% of the time (in the case of a business). Hydro projects (water) handle this the best because the energy / prime mover (water) is always available and easy to convert and manage.

Then this brings up the "timing" issue. If you are running equipment that needs carefully calibrated machine speeds (i.e. 60Hz input) guess again. Most inverters that push 3 phase or 1 phase power have a margin of acceptable operating range. To get exactly 60Hz can be very difficult. If you are thinking about large CNC stuff you may have a timing issues with the motors.

The best possible way to accomplish all the things you want to do is this:

The 2 Phase leg method is possible. This uses a Delta Configuration transformer that is missing one of the legs (coils). The system diagram looks like a triangle with one of the sides missing. I can believe (it's been a while since I looked at something like this) you can slave that coil to a Y configuration and have 3 phase power. I think the proper terminology is OPEN DELTA - WYE configuration. It works.

Alternative power is a novelty or an expensive requirement when grid power is not available. It is not the cheapest or most cost effective solution for constant or heavy loads. Diesel follows next for high power loads (but remember with diesel your getting a 50% loss of energy through generation / conversion from chemical energy to electrical - IF your system is amazing).

If you want to build a system that pays you back and makes economical sense to run do this:

Offer to purchase the transformer for the utility. Go with a 200 Amp Open Delta to Y Transformer (it may be figured out in KVA = Volts * Amps * root3).

Then connect this to your building. Now you have your "reserve/battery" power. This gives you three things that are very expensive to do non-net. (a) power timing and (b) surge capacity (c) RELIABILITY.

Next investigate your alternative power generation options. Build the wind system so that it can push 3 phase power at a constant speed at your "TYPICAL" wind speed. This will be like filling a pool, you are trickling the power back into the grid constantly day or night you can recover the cost of your original install in a few years if the cost of energy is high in your area.

The cost of converting the power from your turbine / generator to the grid can be expensive and there are books full of options to go with. I like the automated management / battery systems that take power via DC and invert and you resell at the appropriate AC voltage. There are a few companies out there that are building ready to go turbines, their kits are smart and usually automated!

good luck, PM me if you want more talky talky.

Viper, you are between a rock and a hard place with the power company. You might figure out what your peak load now is for starters, then double, triple, (or more depending on plans). Then go talk to the REC and ask them where they have that kind of power available. Maybe you can find a piece of dirt you like that already has a suitable line running by.

You might also ask them about USDA rural development grants or other programs that might be available.

As for rolling your own power on diesel, it will make power company juice look cheap. I looked hard into it back when diesel was $.90 and electricty was $.12kwh. I had a use for the waste heat for 8 months a year and it would barely work. The other 4 months it would sit unused. Waste heat just isn't worth much in the summer, especially today!

Guys, I tend to agree that relying on wind alone just would not work for a business solution and I did not know we would have problems holding frequency with the wind power but it makes sense if the wind rotor speed is always varying. I am having REC send me a map of where the 3ph lines are that they have. I have been asking for a LONG time for this some hopefully this will help.

I guess the thing that pisses me off is they want to charge a TON to run wire to me just so they can charge 1k/mo for power!! I am also looking at a large diesel unit with bio fuel since we planned to do that anyway for our diesel trucks. I would have to say that may just become a huge hassle.

The reason I did not want to hook into the grid was that I believe the power company has specific gear they want installed to hook up and it is VERY expensive. I can certainly understand safety of linemen but I can build my own switch gear for power outages.

I am also in the gray about how synchronizing with the grid power or if that even needs done. Separate grounds and neutrals, seems problematic to me.


I have also looked at the battery ideas and it would seem I could need around 450 deep cycle batteries for my needs. That simply is NOT feasible.

Interesting...

My power company told me they would hang whatever size transformer I want on the line. I'm also on a single-phase rural service.

Unless they put a demand meter on your pole, they have no idea what size motor load you're starting.

I say have them hang a 75kVA on the pole and tell them you're running a "welding shop". Offer to pay for the transformer, if required. They're about $1,500 +-.

These guys are a serious pain in the ass!!! They "say" they will detect a large pull because the lines just suck that bad. Sounds like someone needs to spend some of their own money and upgrade some shit!

I am not sure how big of a 1ph service I can get but I really doubt I can get anymore than the standard 200A/240V service. 1500 for each transformer???? What torques me is I do not even own it! What am I paying for? Maybe I can convince them to allow an outside contractor do the work.


They have already told me that they will eat the first 2K for a home hook up but nothing for a shop! What gives? My pull will be much more than what a house would be. See, in the city, our service provider looks at what you will run, then calculates what you would spend on electric in the next 3 yrs and that is what you get to take off your install bill. That is a GOOD deal! That seems like the service provider WANTS new business!

Quote:I did not know we would have problems holding frequency with the wind power .

You won't. There are two different methods of generating for gridtied wind:

1) generate DC with the windturbine and feed the line through a synchronous inverter, which handles voltage, frequency, synchronous and safety issues. The leader here is Bergey Windpower at Bergey.com. Find your location and wind classification on their windmaps and download their WindCad spreadsheet for output predictions for their Excel turbine. It's their largest machine and the only one of its type that will come close to supplying your load. Also, follow the links to find out what the Kansas net metering rules are.

2) Induction generation, in which a slightly modified induction motor is driven faster than synchronous speed and backfeeds the line. The induction generator is dependent on the voltage and frequency from the line and gives back what it gets. No synchronous inverter needed. It's not new and has been used dependably for over 50 years. Enertechwind.com (also in Kansas) has these units, along with Prairiewind, Endurance Wind, etc.

Quote:
The reason I did not want to hook into the grid was that I believe the power company has specific gear they want installed to hook up and it is VERY expensive.

The utility may be yanking you around because they don't want you to interconnect to them. Unfortunately for them, they HAVE to. So do some reading, arm yourself with the knowledge and be firm.

Quote:
I am also in the gray about how synchronizing with the grid power or if that even needs done. Separate grounds and neutrals, seems problematic to me.

Synchronizing with the existing signal is done in the electronics or the induction generator. Your installer or the company you buy from will know how to wire it. There's nothing new or difficult about it, it's just a little different. It's all National Electric Code.

Tax credits are good right now. 30% of total installed cost at the federal level plus state incentives. So factor that into your cost.

One thing's for sure, though. You ain't gonna build your own and throw it up and carry the loads you're talking about. If you're interested in DIY stuff, see Otherpower.com. Study up on energy conservation (also eligible for 30% tax credits), lower your loads if possible and good luck!

neil

I've been in the wind business for 30 years, FWIW.

The induction genny is fine, but still has problems.

You need to be sure to push it into generation, or disconnect it, because if you are not having enough wind to drive it, it will become a very large and expensive fan, sucking grid power and just creating a wind.

The usual solution is variable pitch blades.

There is also the problem of hooking up..... you need to drive it to speed, and hook up when near synch. otherwise you will be "dropping" a large motor on the line and they just hate that..... in fact there are usually rules about it, as per the IEEE spec (IEEE 1547), which covers "distributed generation". There are limits on the current drawn when paralleling devices close.

Even an induction generator does NOT meet the safety portions of IEEE 1547 without expensive extras..... You must drop out entirely if the grid moves out of frequency or voltage limits. Your required dropout time is measured in LINE CYCLES, and not many of them, either.

You have to be off before their reclosers start to re-try in case of an outage when re-closers are involved. And you must wait a specified time before a re-connect of your DG (your generator) to the "area EPS" (powerco).

Basler makes a couple units which will monitor the grid and drop you off under the required conditions, but they cost a couple grand, and do NOT include the contactors, safety switches, etc.

The powerco may require a certain brand and type of interconnect switch. if so, it will probably NOT be a cheap one......

Some of the rules are different if you are under 30 KW, but much of the requirement stays.

Intertie is a pain.

Keeping entirely separate, or partial powering of some loads with local power with a transfer switch for full grid power, are valid alternatives.

But keeping separate is a nuisance, unless you have water power..... it is the finest power there is, and pretty much trouble-free, with 24/7 availability.

The others (wind, PV) are 'as-available" sources, and will not be available when you really need them, just on the principle of the inherent cussedness of things.......

Comments about hydropower, not that these will help the OP, who seems to be in
"power hell" if ever I could imagine that place.

North of peekskill is a town called cold spring, NY, and north of that along the hudson
river, is an old estate that has since been donated to the state for hiking land. But
there is long concrete road that winds up into the hills, and halfway up there are the
ruins of the buildings that the estate owners used. Farther up the trail, after
crossing the aqueduct, there is a stream that drops from the ridge and flows all the
time.

There is a small concrete blockhouse by the stream, below an old dam. In the house
are the foundations for old machines, and it seems pretty certain that they had
some sort of generating plant there, powered by some kind of water power, maybe
a pelton wheel. My bet is that the entire estate was provided with electric power
from this setup. I think the pipes that fed the water, were maybe six inches or
so in diameter. And the dam was probably hundreds of feet above the house.

From that one could probably compute the available electric power from this,
given a reasonable conversion rate - ten percent maybe?

Jim

Originally Posted by jim rozen

.....From that one could probably compute the available electric power from this, given a reasonable conversion rate - ten percent maybe?

Jim

10% for a Pelton installation? Correctly designed and installed I think you can get very close to 90%; that is 90% of the gravitational PE finishes up going into the generator as mechanical energy and you can get around 80% of it out as electrical. Peltons are probably the most efficient generating system there is but their big drawback is that the head needs to be greater than 200 or even 300 feet. Francis or Kaplan turbines are nest and they do need need as much head but they need proportionately larger flow. Either way they are not that useful in Kansas which is a bit shy of mountains.

Again, not helpful, but I have seen a wide overshot wheel that generated several kW continuously (oe as needed).

head was maybe 6 foot, but lots of flow. Happens even in Kansas. Oklahoma, etc.

A friend of mine (Electrican) has chosen to not attatch to the grid. Solar power, and wind power to a limited battery bank powers an in inverter for smaller loads.
When he runs machines, he has a generator supplying the 3-phase, and this is only runnin short time each day (read when needed)

If you use a wind mill or a hydro- generator an inverter may correct the frequency.

Good luck

dsk

I've been in the wind business for 30 years, FWIW.

Neil,

I read somewhere that an the UK's wind-farms are only producing between 24% and 36% of their capacity when averaged over a year. Does that tally with your experience of US installations?

Originally Posted by Billtodd

I read somewhere that an the UK's wind-farms are only producing between 24% and 36% of their capacity when averaged over a year. Does that tally with your experience of US installations?

Hi Bill,

Yes, it does, though I should qualify that by saying that my windfarm experience isn't recent- I work primarily with individual offgrid machines.

Capacity factor is more useful elsewhere in the electric power industry-not so much in wind due to the intermittent nature of wind and the ratings games that windturbine manufacturers play. Machine ratings are high for the same reason electric motor Hp ratings have escalated in the last decade or so-it makes them sound bigger. If windturbine ratings were arbitrarily lowered, capacity factor would "improve" even though the machine would be the same.

There are those in our trade, myself included, that are pushing for ratings based on rotor diameter and output over time, rather than the present instantaneous rating. The goal is to encourage more realistic ratings, but the stumbling block is that most people like to make choices based on simple numbers.

neil