In another thread , discussing hum, I wrote about a buzzing sound:

I have a wind-turbine which generates electricity. It is connected to the power company. It feeds and/or we draw. When production exceeds consumption the meter runs backward and we "receive credit". In fact for some months we only pay the connection charge. It does substantially reduce our bill.

billyTHEkid asked for more information:

can you give us some information on your wind turbines. How much they cost, how much power do you get, brand name, do they provide you with electricity 24/7. and so on...

GONK suggested I start a thread when he wrote:


f there's enough interest, you guys could start a thread in The Badlands to kick around alternative energy sources like wind power. It's a pretty interesting topic that I haven't really even poked around in for a decade or so, and never in any sort of practical application like nfaguys is running.

So I guess I will, so here goes the start: In 1999, wondering about future power outages, and, living in Northern Maine where they can occur I got to thinking about non-grid electricity. Yes, I had a diesel generator on standby, though back-fed thru the panel at the beginning (later changed to an automatic transfer switch (ATS). Prior to that time I only had to use it once, but then I got to thinking about what would happen in a real (natural or un-natural) disaster KINDA LIKE KATRINA of late. I thought that so long as fossil fuels could be delivered we'd be OK, but if the infrastructure (i.e. supply-delivery etc) evaporated/disintegrated etc my power generation would only last a finite time, so I sought other means. Fortunately we live "out in the country" on a "farm" with lots of acres. The only zoning or building restrictions were EPA (couldn't pollute) and possibly air-traffic patterns. Checked out the traffic pattern and even a 200' tower was OK at our location. I then checked with code enforcement of our town. They had had no previous inquiries and said OK to a 120' tower. Of course I got it in writing. More: next post.

Continuing:
Let me back up a minute. When considering an alternative source (i.e. "renewable energy") there were two that might work for me: (1) solar; (2) wind. Hydro was out, since there is no stream on our property...and it needs to be close to reduce line loss over distance.

Having checked out "INSOLATION"(solar resource) I found what I suspected: WE DIDN'T HAVE ENOUGH TO MAKE IT WORTHWHILE. Checking windresource I found we did. Here's how:

Reviewing our power consumption for the previous two years I found the average (daily) consumption in kWh (killowatt hours). Using the average wind resource for our area I calculated the average daily production. I then made an assumption for the purpose of calculation and asked a question:
Given that wind resource would/should be stable over the next decade or so, given that our consumption would stay the same and the cost of electricity would not change [ALL OF WHICH ARE ASSUMPTIONS]....and assuming no down-time (which happened)my simple calculations indicated that payback would occur (considering our total cost for this unit) in 8.6 years.

Now for the thoughts going into the decision for wind vs. solar: In order to produce a similar amount of electricity (i.e. matching the capability of the wind) the cost of just the solar panels to do the job in this Northern latitude was approximately four times the cost of this USED WIND TURBINE. Additionally there would be cost of frames, stands, wire, connectors, etc etc. And there would be a large # of panels in the back yard as well as the roof. So it was unfeasible, though I would have liked it to be feasible.

Additionally, we would require a battery bank and other ancillary equipment, which we obtained anyway, but for our A.C. turbine which is a grid-intertie system batteries are not necessary.

...to continue...

Description of Wind Turbine System:

Ours is a JACOBS Wind Turbine. Jacobs was taken over by WIND TURBINE INDUSTRIES CORPORATION in mid 1980's.
It came from a wind farm in California (or so we were told), where they allegedly removed smaller turbines, replacing them with mammoth machines. Land was at a premium there, we are told and I believe that much. We actually cannot verify the history of our turbine. We bought it because we could afford this one and not a new one, running the #s as I explained above.

It consists of a 17.5 kW generator atop a 120' free-standing tower. The base was 29 yards of concrete and is four feet thick. Since we are on rock I hired a rock-boring machine from a construction company and had them drill three holes 8' deep in the rock, 18" in diameter. That was used because it was their maximum capacity. We filled the three holes with REBAR which was tied to the rebard cage of the 19' x 19' x 19' base, four feet thick. I felt that this may be overkill, but I didn't want the tower to topple over in high winds. Not being a construction person I'm told that there is over 100,000 pounds of concrete in the base.

From the top of the tower there is a run of 350' of two runs of wire to the control box in the garage. One run supplies the DC field to the generator, and is varied according to the RPMs which the control box reads out. More RPMs more DC voltage. The other run of wire sends the produced power into the control box.

The control box is in parallel with the grid. In order to run properly it needs to sync on the 60 Hz frequency from the grid. So without the grid this turbine produces no power.

Being a "grid-intertie" system, and thus always connected to the grid we can see the meter activity. If we consume more than production the meter goes ahead. If we produce exactly what we are using the meter stands still...but we are still consuming. In the wind causes production in excess of our consumption the meter ( *** HAPPILY *** runs backward, taking kWh off our electric bill.

There are months where the charge from power company is only the connection charge, and production reduces the # of kWh recorded on the bill. The power company wanted to install a second meter, one whic would only go forward, and one which would only go backward. This was unacceptable, and I talked them out of it. I would be charged for all consumption at regular tariff rates, including per kWh and delivery. Production would be at at per kWh cost. Power up here is 14 cents per kWh. This way I am essentially "selling" to them at the same price they charge me. With separate meters as above I would pay 14 cents and they would pay me 4 cents.
You do the math....not rocket science. Somehow I convinced them, and I'm not sure how or why, but it works out.

...to be contuinued.

nfaguys

Thanks for the information. Alternative heating and power has always interested me. My brother-in-law and sister-in-law had a business in northern Michigan in the early 70's selling wind turbines and photovoltacics. I turned out to be a bit early in the development of the products and after a few years they had to close up.
When we lived in Maine (Portland) my wife and I renovated a 4 story Queen Anne brick home right in the city. We put a new heating system in that would burn wood, coal or back up with oil if the temp dropped to low in the house. About once each heating season someone in the neighborhood would see the smoke coming from the chimney and call the Fire Dept. It would usually be on a Sunday afternoon the door bell would ring and when you answered it 6 or more Firemen would come rushing in telling me that the house was on fire. After I explained what it was they always wanted to go to the basement to to see what it looked like. 25 years ago there were a lot of wood stoves but not many furnaces.
When we moved to Florida I had visions of wind generation and geothermal exchange for heating and cooling when we were ready to build outside the city. Research I did do showed the possibilities of wind power for the Tampa area as virtually non-existent. The people I have talked to that have done geothermal keep saying they don't think its worth it. I keep looking for people with the answer I want and someone who has been successful with it since there is a lot of 60-70 degree sand not to many feet down.
Please keep writing about any part of your alternative power and heat/cooling choices that cross your mind it's quite interesting

Hi Brad.

Interesting historical in your note, regarding the fire dept and your situation. We do burn wood in the fireplace in winter, and were considering adding a wood stove to the large kitchen (just enlarged last year. I'm no authority in any of this. Everything I know I learned OTJ (so to speak).

Regarding heating: In Northern Maine as you know we have no gas. Heating is usually either oil or wood.
We bought a wood boiler as an alternative in case oil became scarce or non-deliverable. Hasn't happened yet, though prices are higher. Wood boiler is available for installation should we so choose.

Regarding cooling: We rarely run the air-conditioners. We have split units. Summers are generally nice and at nite it's extremely pleasant.

Regarding alternative power: besides the above wind system (and the desire but impractical cost of PV) we have standby generator(s) and battery backup which I'll detail in another post.

,,,to be continued regarding generator backup.

ABOUT GENERATOR BACKUP:

I said above that after first buying the house I had an electrician install a hookup outside for the "pigtal" from a 17 kW Kubota diesel generator. It backfed thru the panel, requiring manual switching by me when in use. The 50 AMP 220 v breaker had to be enabled and the main breakers disabled for lineman safety. Not code. Changed as soon as practical, but we used it when needed.

My system now consists of a number of components.
First there are two generators. One is diesel (17 kW Kubota. The other is propane (17 kW Martin Machinery. They make OEM for caterpillar. There is a manual tansfer switch, allowing a choice of either one. I did this for fuel diversity.

I have also a battery bank of 48VDC at 1800 amp hours. There are 24 2 volt cells in series. These are connected to the DC side of my two TRACE (now Xantrex) inverters, models SW5500. So they generate a sinewave and have 5500 watt capacity. Since there are two they supply both phases of a 220 v system. They are in sync with the grid and totally independent of the wind turbine system.
If the grid fails and my other manual transfer switch is set to what I call INVERTER PRIORITY (my idea and my nomenclature) the inverters will go to battery when grid fails and the house runs seamlessly on battery power, being conerted to AC by the inverters. When voltage falls below user-defined parameters for user-defined period of time (and if grid still down) the inverters will tell the generator to start. Batteries are now charging thur the inverters, and the house is running on generator.

I mentioned MANUAL TRANSFER SWITCH (MTS). This tells my system whether to pay use the batteries and inverters, or, if those are down or out or if I so choose, in another position of the MTS the grid failure tells the generator to start (and we don;t go on battery) via an automatic transfer switch (ATS). So as you can see I really have it both ways. Wait there's more.

More: Because we might be running the house on battery during a power failure, I decided that it would not be a good idea to run the dryer, dishwasher, oven (i.e. heavy resistive loads) on battery. So I had the electrician install a SUB-PANEL just for non critical loads, and it also includes the driveway lights. Here's how it works. When there is a power outage a latching contactor (which gets energized when power is present at a breaker) drops the non-critical subpanel. We know this is dropped because a red light comes on to indicate such. So we push a button to reset the contactor and I can pick and choose which loads (if any) I wish to allow at the time.

This has worked well for us and I've not had any problems. It cycles when there is a power outage.
As previously mentioned Southern Maine had ice storms several years ago and people were without power for a long time. I don't want to be.

NOW MY WISHLIST: I would like to be able to run my Jacobs windturbine and have it generate DC just as photovoltaics (PV) will do, and as does a Bergey wind turbine. But I want it to also have the AC grid-intertie which it now has. I want my cake and I wish to eat it, too. Jacobs agrees it can be done (easily) but doesn;t think there is a market for it. I think I know the general principles involved, but I can't do it myself, so I'lkl have to accept what I've got so far, which isn't too shabby .

Didn't mean to have long-winded (no pun intended) explanation

I hope this is of interest.

Thanks for the info! What kind of maintenance does the turbine require? How do you reach it. Jim

I have maintenance done twice a year. A mechanic-type climbs it (freestanding 120' tower). He changes the oil, grease-lube everything and everything. Checks every bolt on the tower and blades etc for tightnes.

Excellent writeup(s) nfaguys...very interesting. Did you need to take any special precautions regarding lightning?

Thanks for your comments, rance. and YES:
Regarding lightning: all three legs of the tower are bonded to 8' grounding rods, driven into the ground. They are all tied together with ground wire to create a "ground plane", according to the electrician.

I addition the rebard "cage" within the concrete base is connected to the ground plabe. I left threaded rod and rebar projecting fromm each of the three sides of the concrete base. So I guess this adds to the plane.

I love good grounds. Have not (cross fingers) had a hit.