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  • Small Scale Wind Power Analysis – Fail

    Posted by Dan from Madison on May 13th, 2010 (All posts by )

    I have mentioned that I am the proud owner of a hobby farm. On it we have five head of cattle, a couple ponies, a few chickens and that is it the last time I checked a week or so ago. The farm is about 20 acres.

    Recently I did a cost analysis of setting up this property with a windmill to power the place. My vision was to get “off the grid” and have a place I could retreat to and survive in if a natural disaster or act of terrorism happened, as well as getting “free” electricity and perhaps selling juice back to the grid as I have read others have done. I am very impressed with the small solar powered items I have bought and installed at the farm – they power the electric fences and provide power for some outdoor lighting. These items were relatively cheap and easy to install. You can get them at virtually any farm and/or retail store.

    Doing the research for this project I learned a lot. The first thing I did was email the local utility, Madison Gas and Electric. Within a few hours they referred me to Focus on Energy. You can read about who makes up this organization here. Basically Focus is an organization that encourages and helps people and businesses to conserve energy and buy appliances and systems that will use less energy in the future. They also have rebate programs.

    I didn’t have accurate data for the amount of electricity that my farm used over the past year, but I did have the bills. They are less than the usage at my house, so I used my home bills as a baseline. On average my house uses (or should I say we use) 1158 Kilowatt Hours (kwh) per month of electricity. The high months were January at 1,756 and December at 1,771. The lows were 747 in May and 905 for August (we had a very cool summer last year). The total usage in 2009 for my house was 13,897 kwh.

    If you take a look at the Focus on Energy website there is a TON of information on wind power. I took many of the following conclusions from the information presented there.

    To completely power an operation the size of my house with wind generated electricity I need approximately 14,000 kwh per year. I probably need less for the farm, but still it is a good number to use. But there are a few caveats. One is that any windmill or turbine needs to be thirty (30) feet above any structure or nearby trees to capture the best wind for usage. The planned site for my turbine was going to be next to the barn. The barn stands approximately 50 feet tall (maybe taller, I never really measured) so the turbine would need to be somewhere in the 75-100 foot range up in the air. This may be a zoning issue as my farm property is in the flight path of a local tiny municipal airport. I don’t think this is an issue but regardless it is a good point that my wife brought up.

    According to this page at Focus on Energy I would need the model ARE 442 with a 12 mph wind or the model Gaia-3 in a 10 mph wind. And that is something else I learned. The efficiency and power output of the turbines collapse in a huge way when you get below 10 mph. Fortunately, Focus on Energy has wind charts for 10 mph and up for the State of Wisconsin. Here is the chart at 30 meters, and here it is at 40 meters. I look good at 40 meters, but at 30 it is close – very close. Also, I have some hills on my land which doesn’t help any. By the way, 30 meters is almost 100 feet in the air. I don’t think looking at this information that I could keep the 10 mph target at my property. Large chunks of the State of Wisconsin fall under this, as a note of interest.

    But lets say that I can hit the 10 mph mark, just to continue this discussion to the end, the money part. The smallest unit I can use to fulfill my needs would be the Gaia-3 – BUT this is a three phase unit and I have no need for three phase at my farm. So, I would have to pray that the ARE442 unit would work (rated at 11,220 kwh at 10mph and 17,520 kwh at 12mph) or the Jacobs 31-20 unit (rated at 12,750 kwh at 10 mph and 21,990 kwh at 12mph). Again, there is a lot of praying involved to hopefully keep up that 10 mph wind, at least according to the wind charts provided by Focus on Energy.

    According once again to Focus, the installed cost for the ARE 442 as of January 2009 is $71,000 and the Jacobs 31-20 would cost $80,000. Of course these are cocktail napkin estimates – the final cost could be lower, or higher – but these are good ballpark numbers to use.

    Here is a bit of good news though – the feds (that is you and me) will give me a 30% tax credit for the cost of the turbine. And Focus on Energy will give me a maximum of 25% of the installed cost back (but this depends on the amount of energy generated so is not a hard figure – you can find it here) and any and all wind power stuff like this is exempt from Wisconsin state taxes. The Focus on Energy rebate dollars are only payable after one year of data collecting so if you believe in inflation as I do, those dollars will be worth less by the time I would get them. So in the end, lets just say that after the installed cost it really isn’t worth it. And remember, I need to pray that the wind stays above 10 mph or this is all pie in the sky.

    Oh yes, one more thing I forgot. This. She isn’t sure that she wants to see this thing some 100′ in the air chopping up the cute birdies. Huh.

    Well, I learned a lot from this thought exercise. Wind power for farms I would imagine would be a great thing if you used a lot of power. But for my little hobby farm, I think I am much better served with my money getting a natural gas generator in case the electric goes down (my disaster plan). Or doing nothing at all.

    After looking at and analyzing my electric bills, I have started a program at my house that includes the family members to try to get everyone to quit leaving lights and TV’s on all over the house. If we do well I will take the family out for ice cream once a month. I project I will save over one thousand dollars a year from doing the simple things, but that is certainly grist for another post.

    Cross posted at LITGM.

     

    32 Responses to “Small Scale Wind Power Analysis – Fail”

    1. Jonathan Says:

      The wind speeds marked on the map are averages. How variable are they? The more calm periods there are, the less practical a wind generator would be as a source of full-time emergency power. And you could probably buy a reliable multi-fuel generator for a fraction of the cost of a windmill.

    2. Dan from Madison Says:

      Tough to know how variable those averages are. You can also spend more money on better batteries to get you though periods of no wind, such as we have today here in Southern Wisco. Agreed, a nat gas/diesel generator is the way to go for me, if I decide to go there.

    3. Tatyana Says:

      …or, you could do a mini-version of a big utilities companies’ policy on your own, small-scale “project” – to invest in a combination of various sources. Say, solar panels of the roof of your barn, plus batteries, plus small emergency generator, plus a windmill. Or, if that proves too ineffectual (expensive vs. your farm’s income) you could cooperate with several neighboring farmers, form some sort of cooperative energy production.

    4. Joseph Somsel Says:

      So the small wind example gives the same result as the large wind (grid) example – FAIL.

      You didn’t even get into the problem of matching wind-generated power with your own usage patterns. Of course, some will advocate electric storage devices (like batteries) but that’s an extra LARGE expense and the round-trip efficiency is roughly 75-80%.

    5. Dan from Madison Says:

      Joseph Somsel – “You didn’t even get into the problem of matching wind-generated power with your own usage patterns.” Pretty much – I didn’t even need to go there after the basic cost analysis.

    6. Dan from Madison Says:

      One other cost factor that I failed to mention – maintenance. I sure as hell am not going up there to oil the damned thing or do whatever needs to be done to a turbine, more expense. And I am still not sold on the fact that the things won’t ice up in our brutal Wisconsin winters.

    7. Paul Milenkovic Says:

      Dan From Madison, turn back from the supply-side solution to electric power and look towards the demand side! I tried in vain to get Marc “Armed Liberal” Danziger over at Winds of Change not to waste his money on a solar panel. He might know his firearms and how to not get gun oil on his good suit, but as a matter of fact, I Am an Electrical Engineer (IAAEE) and know more about electric appliances.

      There is an enormous amount that can be done by energy efficiency using readily available lighting and appliances, things that actually pay themselves back. I live in Madison with gas heat and hot water and electric everything else including air conditioning, and last year I averaged 220 kWhr/month.

      Some of that is fluorescent lights and motion detectors, some of it is Energy Star appliances, part of it is some “tricks” (no, not scientific fraud) such as running the clothes dryer to a “damp dry” instead of “bone try” and putting the clothes up on hangers in the shower afterwards, using humidity gauges to adjust the dehumidifier setting and pattern of A/C usage, setting the microprocessor board DIP switches to low airflow settings on the furnace. Some of it is simply turning stuff off.

      I know one fellow I met at an “energy policy lecture” who gets by with about 100 kWh, but he doesn’t seem to see the need for A/C, and he lives alone — I am thinking he pushed the energy-saving to the point where he pushed his wife out of the house and his life. But there is a lot you can do short of that.

    8. Joseph Somsel Says:

      Paul,

      I can’t even get my family to WASH their clothes, much less babysit the drying with labor-intensive but energy-saving techniques.

      I could improve furnance performance though – I’ll take the hit on that. However, I rent in California – it’s not mine to improve and we don’t use that much heating.

    9. Dan from Madison Says:

      Paul – I hinted to that at the end of this post and hope to have a follow up in a few months after I train my family to turn off the damned lights (among other things). But I won’t be without my incandescent lighting, I simply cannot stand the cold sh1tty light that the compact fluorescents give off.

    10. TMLutas Says:

      I think that this sort of analysis is more useful if you go all the way through and figure out at what are the variables in motion and how much would variables have to drop/rise for this solution to make sense. For instance, if Wisconsin passed a $10/KwH tax on grid power, I think you’d find that non-taxed wind would suddenly be a great financial deal. The utility of this is twofold. As prices drop on these alternate energy solutions, you can start redoing the calculations when they start coming close to break-even. Also, knowing the gap enables you to get a pretty good guess how high green politicians *really* want to tax conventional energy.

    11. Shannon Love Says:

      You won’t be able to run the farm off wind or solar because you can’t store the electricity in anything approaching an efficient fashion.

      I think it very telling that farmers don’t even use windmills much to pump water anymore. You would naively think that would be a no brainer. You just pump water up into a tank and then drain it out when you need. If you have good wind, you fill the tank up and if you have poor wind, you just drain the tank. Yet, diesel and electrical pumps have wiped out all but a small number of windmill water pumps.

      Just in the case of water, storing useful amounts of water is a big undertaking. If you want to store it so you don’t have to pump it, you got to have an elevated location for the tank. That usually rules out any simple in ground tanks so you often end up with a large above ground tank which is expensive and has to be maintained and cleaned often. If you need more water than you have stored such as for irrigation or fighting a fire, you just can’t dial up the windmill. Your stuck with what water you’ve already pumped and the wind speed at that exact moment.

      Then you have the entire nerve racking fun of repairing a windmill way, way up in the air. One of my grandfathers first jobs as a teenager in the late 1920’s was repairing windmills out on the dusty arid planes of eastern New Mexico. He had some hair raising episodes.

      The simple truth is that we use power in the first place so that we don’t have to operate on nature’s schedule. Wind power does operate on nature’s schedule so right at the get go its nearly useless for what we need power for.

      Contrast a windmill with a simple diesel pump. You don’t need to store the water. You can dial the pump up and down at will. You can easily afford excesses capacity for times you need significantly more water. It’s small, compact easily protected from the elements and, oh yeah, you can repair with you feet planted firmly on the ground.

      If you’re looking for emergency power, I recommend a gasification rig. These rigs can (rather inefficiently) covert almost anything that will burn into a gaseous fuel that can run generators and vehicles. Better yet, they are portable. For a few thousands bucks at most, you could have a reliable emergency power supply that would work round the clock, rain or shine and which you could run with if you had to.

    12. Dan from Madison Says:

      TMLutas – agreed, the cost will more than likely come down in the future and may be worth analysis at a later date. Hopefully the technology will improve as well – if the wind isn’t there, as according to the charts it isn’t, it won’t matter anyway. IOW I need more KwH out of less wind at the place my farm is at. I assume that the tech will also improve over time.

    13. Tatyana Says:

      Dan, you are not buying the right CFs. Look for “warm white” marker, or a CCT of 2700-2750K; that’s the temperature an incandescent gives out, and there are some CFs in this range.

      Paul, I’ve noticed that techno guys often have this tendency to be excessively fanatical on some subject, be it elec. bill savings, or Star-trek convention, or diesel-punk watches…

    14. Shannon Love Says:

      Paul Milenkovic,

      turn back from the supply-side solution to electric power and look towards the demand side!

      Why? That defeats the entire point of using energy in the first place. Sure, you can save energy by simply not doing things but if you’re going to do that, your just making yourself more materially poor. After all, I doubt the peasant women in Mexico washing their clothes by hand in galvanized tubs by the river side are using less energy than I do with my washer and dryer but I don’t want to live like that.

      Besides, energy efficiency is self-defeating if the goal is the lowering of overall energy consumption. An economic effect called Jevon’s paradox mandates that any increase in efficiency of a technology, especially energy technology, cause an increased overall use of that technology. It is an iron law, never once observed to be broken since it was first formulated in the 1860s.

    15. Dan from Madison Says:

      Tatyana, thanks I will check it out – but I bought several cases of old school incandescents I will need to burn through first. Maybe I can Ebay them.

    16. Tatyana Says:

      Dan, your best bet is moderation (hmmm…that seems to be the topic of my comments today…), i.e. – in mixing various light sources according to the task needed.
      For lighting the garage, for example, the sharp “true white” fluorescent is better than yellowish warm incandescent – and an added bonus is that it lasts 10000hrs w/o replacement; you don’t want the light suddenly go off when you’re under the hood of your car.
      Usually it is recommended even within one room to have several light sources. Bathroom: a recessed CF downlight, UL-rated for “wet environment” – it’ll give you a sharp illumination in a spot with potential health hazard. The mirror above the sink, though, could be lit with two small halogen wall sconces (incandescent) on each side, insuring warm glow on your Wife’s skin, so she could apply makeup in most day-like light condition (to match the conditions she’ll be seen outside). Your living room’ chandelier could be incandescents on dimmer, and you might want to install a LED ceiling light in an egress corridor so it’ll stay lit in case of fire and smoke infestation.

      Etc, etc. The principle is mixing light sources, like mixing energy sources, or “not putting all eggs in one basket” – is always better.

    17. Dan from Madison Says:

      Tatyana – hopefully my wife won’t read your last comment or that will cost me an upgrade in the master bath.

    18. JaimeRoberto Says:

      I had a similar calculation with solar. My house is in a prime location for solar; unobstructed southern and western exposure and sun 300 days/year. Even with the subsidies in place the payback period would be about 15 years in the best case, and 50% of the payback was due to the increased value of my home. And since I don’t plan to move until I’m much closer to death, the increased home value really doesn’t do me any good. My conclusion was that conservation is by far the most effective solution, though it won’t do much good in case of a disaster.

    19. Tatyana Says:

      Dan – but it’s not an UPgrade, it’s a savings measure! The shower CF downlight only turns on when someone’s in the shower, and the small halogens are low-voltage on a separate switch. When you count the times you had to change your usual A-lightbulb, adding all the 75w – and compare the sum to the CF +lv-incandescents – there is just no question about it!

      Solar panels: why, I wonder, half of Israel homeowners are using them on their roofs? They must be cheaper there.

    20. Paul Milenkovic Says:

      “Paul, I’ve noticed that techno guys often have this tendency to be excessively fanatical on some subject, be it elec. bill savings, or Star-trek convention, or diesel-punk watches…”

      I tell this joke about those “reality TV shows”, especially the PBS versions. They had this “Frontier House” where the people were given some supplies and told to live like their great grandparents on the edge of the wilderness, kind of leaving out that a lot of the great grand aunts and uncles died under those circumstances. Then there was “London Under the German Blitz House” where the family snuggled at night in a backyard bomb shelter and the kids mewled from hunger from the short rations. People forget that (my) parents grew up as those kids, and to think of all of the suffering involved, having those wartime kids as your parents and having to listen to how easy I had it growing up.

      My concept is something called “20’th Century America House.” People will watch the program, under conditions resembling that “Road Warrior” movie and marvel, “They had central heat! And all of the electricity they could want! And big screen TV’s! And they had ‘cars’, where they could go anyplace they wanted any time they wanted.”

      Look, I have this 5-fold reduction in electric use, but I still have hot meals, a color TV, a computer, and central A/C, and I haven’t driven my wife out of the house . . . yet.

    21. Tatyana Says:

      Paul, interesting concept, but it wouldn’t work on American cable: the audience lie in the same conditions as portrayed in the program; who’s going to “marvel”? The viewers all have TVs and computers and whatnot.
      Now, if you want to sell this concept to some South-American cable company…or Mongolian…but I’m afraid you’ll only trigger either a) new wave of immigration (including illegal) or b)new wave of anti-American hatred. Or both at the same time.

    22. Ben-David Says:

      Tatyana asks:
      Solar panels: why, I wonder, half of Israel homeowners are using them on their roofs? They must be cheaper there.
      – – – – – – – – – – – –
      Shalom!
      The panels on Israeli roofs heat water, they don’t generate electricity.
      These systems are an order of magnitude less expensive than photovoltaic technology. They’re basically a bunch of black irrigation piping – or corrugated metal sheet painted black – put in a glazed frame and hooked up to a water tank.

      They do save energy – but the water tanks contain electric heating elements for when the sun isn’t out. And many Israelis have installed super-efficient gas or electric “instant heat” systems for their showers, to supplement the solar collectors.

      Also we use European-style washing machines that heat their own water – which reduces the load on the rooftop systems.

    23. Shannon Love Says:

      Tayana,

      Solar panels: why, I wonder, half of Israel homeowners are using them on their roofs? They must be cheaper there.

      As noted, they are solar water heaters not photovoltaic. More importantly, however, Israel is (1) very close to the equator and (2) in a dessert and (3) in a dessert moderated by the Mediterranean.

      All this makes Israel the near perfect location for using thermal solar energy. You have more intense sunlight, more hours of the day, without clouds, without rain, without hail, without high winds. Heck, the average temperature of the water coming into the house will be lukewarm as opposed to near freezing as it in half the US during the winter. Of course, because it is a dessert, they have to struggle to get the water to heat in the first place.

      If you wanted to live in the Mexican Baja, you could make ready use thermal solar just like the Israeli do.

      I can’t repeat this enough. Alternative energy works on nature’s schedule. If you’re willing to only consume energy when and where nature provides it, then you can use it. If you need the energy to offset natures own lack of energy in the immediate environment e.g. heat in the winter, then you can’t.

    24. Paul Milenkovic Says:

      “Paul, interesting concept, but it wouldn’t work on American cable: the audience lie in the same conditions as portrayed in the program; who’s going to “marvel”? ”

      OK, how about this? The people watching the show are our comfortable energy-sated selves, but the show is “reality TV” about a group of young adults living under “peak oil” or perhaps “Al Gore’s idea of how you will have to live to save the polar bear.” And the participants get to complain about having to walk someplace or about putting makeup on under fluorescent light or about cravings for refined sugar they are unable to satisfy with what they get from a home garden.

    25. Tatyana Says:

      Paul, this is better, except it might not work either.

      If anything my 3-years-reading of ApartmentTherapy (link goes to their official “Green” section, but there is plenty of similar entertaining material in their regular broadcasting) taught me, the younger crowd, led by their Green Shamer Masters is thoroughly indoctrinated in virtuous self-flagellation in the name of Saving Polar Bears (or fill in any other Endangered Flavor of the Day). They all displaying classical abused-children syndrome: they blame and punish themselves for the sins of others – or what they perceive (or led to believe) to be sins of others.

      So there will be no complainers, even if the participants were forced to drink reconstituted-urine-water, produced by their own endless bike-pedaling-pumping. They’ll only feel like heroes, dying for their ideals, you know.

      Would you like to manufacture Martyrs For Environmental Living? I thought not.
      [talking, once again, about fanatical enthusiasts…]

      Ben-David and Shannon: thank you for your explanation.
      I was not suggesting to use solar panels as an exclusive energy source, either photovoltaic or simply “black-body-heat-collectors” (it’s not black-body, of course, but I can’t think of a correct term now). Rather as one of the elements in a building power supply, one of several supplements – as it seems, in fact, it has been used in Israel. Since we here use electricity (or gas water heaters which, anyway, are piloted by electricity) to warm our water – why not harvest free solar energy to do it, and save a bit on electric bills? Even if its reliability is seasonal and climate-dependent, still: every bit counts.
      I can see some homeowners in Arizona or NM installing these panels to lower their summer electrical A/C bills (which must be enormous). Why not?

    26. Shannon Love Says:

      Tatyana,

      … why not harvest free solar energy to do it, and save a bit on electric bills? Even if its reliability is seasonal and climate-dependent, still: every bit counts.

      Because nothing is free. The cost in all senses, time, money, energy, CO2 production etc of the new system probably means that the marginal system will do more harm than good. Every little bit may not count. In fact, every little bit might dig you deeper in the hole.

      For example, it has been estimate that solar and wind generators will have to operate for 5-10 years just break even in saving enough CO2 to offset the CO2 created by their manufacture, installation and maintenance.

      To often these systems are evaluating with unidimensional criteria e.g. saving on the utility bill. However, evaluating the true cost of a system requires a multidimensional analysis of many, many tradeoffs.

      This is the kind of complex equations that only experimentation in the free-market can solve. If people were left free to experiment with these systems, then there would be no reason for people like me to have to make such an effort to point out their limitations.

      The problem is that to many people want the government to force the adoption of the systems by either (1) simply requiring people and institutions to adopt them under penalty of the law or (2) forcibly taking money from some people to bribe others to install the systems. In this kind of coercive environment, it becomes very important to make the limitations of such system brutally explicit.

    27. Tatyana Says:

      Shannon, I meant the solar water-heating glazed panels Ben-David described, not the solar power generators.
      If I understood correctly, these panels are just lying on the roof absorbing heat – no power generation and no bi-product of CO2.

    28. Sam Says:

      Shannon,
      Back in the 1990s I attended a seminar on using photovoltaic arrays to pump water for rural stock watering. The payoff in this case was to reduce or eliminate miles long low voltage distribution lines that feed a 100 watt or so water pump. The seminar was directed at rural electric coops that were serving the stock watering loads.

      In this application, the PV made a lot of sense, much cheaper than grid power. The array was sized to power the pump and the stock watering tank was the storage medium – large enough to ride through nights and cloudy days. Unfortunately, powering stock watering tanks or oil well telemetry is not a very big user of PV panels, so instead they are put on peoples roofs and expected to compete with grid power. Maybe some day PV will be competitive with grid power, but I’m not holding my breath waiting.

      Sam

    29. Shannon Love Says:

      Tatyana,

      … these panels are just lying on the roof absorbing heat – no power generation and no bi-product of CO2.

      Their manufacture generates CO2 and rather a lot of it. People assume that most of the CO2 generated by technologies such as cars comes from their fuel but around 25% of their lifecycle CO2 production comes from emission related to their manufacture. Complex vehicles like hybrids can actually have a higher lifecycle CO2 production than a conventional car of the same specs.

      In the case of these alternative systems, they have to save enough fossil fuel consumption over their lifecycle to offset the CO2 burden of their manufacture, installation and maintenance. It’s very doubtful that they can.

      Since cost eventually boils down to energy consumption, you can simply use cost as a proxy for energy consumption. Since most manufacturing energy still comes from fossil fuel sources, you can use about 70% of the cost as a conservative proxy for CO2 emissions. (The CO2 emissions across different fossil fuels systems are roughly comparable.)

      So, if I install a thermal system that cost $10,000 then its manufacture emits as much CO2 as generating $7,000 of electricity from fossil fuels or burning $7,000 of gas in a water heater. In the long run, I have to save at least $7,000 just to break even on CO2 emissions.

    30. Tatyana Says:

      Shannon – all of this would be valid if the concern about harmfulness of CO2 was valid. And I become less and less convinced that it is so.

    31. Shannon Love Says:

      Tatyana,

      CO2 production, rightly or wrongly, has major policy implications today. That’s why I bring it up. However, it is the same for any criteria.

      The problem with “alternative” systems is that can’t carry the full load. You have to have 100% “conventional” system backing the alternative system such that the true cost of the system is the conventional + alternative. Even if your goal is just saving on utilities bills it takes years, often over a decade for even an inexpensive thermal system to pay off.

      There’s nothing “wrong” with people who live where nature provides energy spending money to harvest that energy as long as they don’t insist that the rest of us pay for it. However, as I noted, these system are romanticized to such a dangerous degree that many feel justified forcing the rest of us to use them or pay for them. For example, look at how you phrased your post question on the subject: “If these systems don’t work why does everyone in Israel use them?” That could be taken as “Israeli use proves they work therefore our resistance to them must be irrational so we could justify passing laws to force people to use or pay for the systems.” In reality, Israel can only use the systems because of the specific natural environment of Israel. 95% of North America has no hope of using such systems.

      (Yes, I know you personally would philosophically not support such force but someone else reading this might.)

      That is the reason I lean on them so hard. I am attacking the romantic fantasy that drive political action that drives force.

    32. Tatyana Says:

      Shannon, but I didn’t phrase my question the way you remember it! I said, specifically:
      “Solar panels: why, I wonder, half of Israel homeowners are using them on their roofs? They must be cheaper there.”

      “Cheaper” does not mean “Israeli use proves they work therefore our resistance to them must be irrational”. It does not even mean “If these systems don’t work why does everyone in Israel use them?” Don’t you see the difference?
      It was a totally neutral question and limited to economical factor. Nothing more!