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Has a San Antonio Inventor Solved a Problem of Small-scale Wind Power?
www.texasmonthly.com ^ | August 10, 2023 | By Michael Agresta

Posted on 09/06/2023 11:09:36 AM PDT by Red Badger

Tinkering in his backyard, Dan Marsh aims to devise an efficient source of electricity for suburban rooftops and beachside barbecues.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

On arriving at Dan Marsh’s home in the King William Historic District of San Antonio, the first thing you notice is the oddly modified truck in the driveway. A custom wooden platform sits on the front of his 2013 Ford F-150, where Marsh can bolt various small wind turbines—miniature windmills that generate electricity—to take for a “spin” on the Interstate 35 and 410 frontage roads.

With help from his wife and a teenage neighbor with a beginner’s interest in engineering, Marsh has performed several such test runs, logging the voltage generated by each turbine while highway-speed winds turn the blades. The 64-year-old retired HVAC professional and amateur inventor is out to prove he has solved a key problem in scaling down wind power generation to the consumer level—small enough to someday efficiently power a home from a rooftop or a backyard.

Based on these highly unofficial field tests of the prototype he’s been building on his back porch and commercial models available on Amazon, as well as lab tests arranged through the EPIcenter Energy Incubator and Accelerator in San Antonio, Marsh claims that his proprietary-technology Pirate Wind Turbines will someday produce 30 percent more power at 40 percent lower cost than currently available models, while drastically reducing noise and vibration to boot. His biggest roadblock, he says, is funding more long-term testing and prototype-building. He is seeking investors.

“The military loved my bracket on the front of the truck,” says Marsh, who has met with representatives of the U.S. Air Force through a mentorship program at Texas State University. “They said, ‘That right there tells me who you are, that you’re not going to wait for money, you’re not going to wait for anything, you’ve got an idea and dammit, you’re gonna get it tested.’ ”

POPULAR VIDEOS PreviousNext Indeed, the goateed, gregarious Marsh is about the furthest thing imaginable from an ivory-tower research scientist. He’s a lifelong tradesman who spent 23 years servicing commercial heat, ventilation, and air conditioning systems on hot Texas rooftops before moving up in the industry to become a project manager, overseeing the installation of HVAC at high-tech factories for companies such as Intel, Micron Technology, and Motorola.

His gearhead tendencies date back to the fourth grade, growing up in Austin, when his father suggested that he try taking apart and reassembling the family lawnmower. Soon Marsh was hooked on working on anything with wheels. He built BMX-style bikes and, eventually, modified motorcycles, cars, and trucks. While enrolled in an HVAC program at Texas State Technical Institute in Waco, Marsh took up street racing for pocket money. His vehicle was a souped-up 1972 Toyota Hilux—a boxy truck, not your typical racing machine.

“My truck was so badass, you could actually feel the ground shaking,” he says. “I’d have people in Corvettes and Camaros and Trans-Ams opening their windows, looking around trying to figure out where the noise was coming from. Then I’d look over, and there’s a special nod, you know, we’d point to the light: ‘Mm-hmm.’ ‘Yeah.’ And then when the light turned green . . . Those were the good old days.”

As Marsh grew older, his tinkering shifted from speedy vehicles to renewable energy. At a previous home in Canyon Lake, featured on a 2009 episode of Discovery Channel’s Renovation Nation for its custom-built green technologies, he was an early adopter of home solar power and geothermal heat pumps. Marsh also tried mounting a wind turbine on that house, hoping to run his pool pump with the energy he generated, but he had to remove it because of excessive noise and vibration.

“Even though the instructions said, ‘Don’t bolt this to the house because of vibration,’ I was like, ‘Well, how bad can it be?’ ” Marsh says. “And it was horrible. It vibrated all the two-by-fours in the house.”

Small wind turbine technology, he learned, has long been limited by the problem of excess voltage generation in high winds. If too much voltage reaches the charge controller box, it can melt expensive components and even cause a fire. It can be hard to avoid a meltdown during storms and other high-wind events. Traditionally, the two ways to stop a wind turbine from generating excess voltage are to design the blades to furl—that is, to turn away from high winds—which leads to noisy vibrations, or to apply some sort of physical or electronic brake. E-brakes, however, can be quite expensive, costing nearly as much as the rest of the turbine combined.

Marsh believes he has found a way out of this dilemma with a patent-pending “secret sauce” he declines to discuss in detail, which he says can limit the amount of voltage generated so that it never exceeds what a charge controller can handle, even as high winds spin the turbine blades rapidly. Marsh has driven his truck-mounted turbines at up to 75 miles per hour, a speed that should be more than double what’s needed to damage a charge controller unprotected by an e-brake—but, he claims, his components did not catch fire or melt, thanks to his proprietary technology.

Because Marsh’s technology is so new, few engineers have gotten a chance to independently assess its potential. Mark McHenry, marketing manager of Morningstar Corporation, a leading producer of charge controllers, who has talked to Marsh about his plans and experiments, says, “I don’t have his turbine in my lab, but what he’s trying to do, sure, that sounds very good. That’s important, no question about it.” McHenry affirms that Morningstar controllers, like all others on the market, tend to melt down if fed too much voltage.

One industry figure who has observed a bit more of Marsh’s testing is Hauke Roeschmann, an MIT-trained engineer with a background at Dell and in management consulting. Roeschmann is an entrepreneur-in-residence at Texas State and serves as an advisor to winners of the university’s New Ventures pitch competition. As such, he has been working with Marsh on Pirate Wind Turbines for much of the past year, introducing him to contacts in government and industry and helping arrange a student-led long-term test of Marsh’s turbines on the roof of the campus engineering building this fall. “What the early tests seem to prove needs to be borne out long term and in a larger test, but so far, so good,” Roeschmann says of Marsh’s turbines. “He’s a crafty little guy.”

Roeschmann suggests the military might be interested in small turbines as a way to provide power to remote clandestine positions. “What if you were to drop into, let’s say, a remote observation spot where you can’t have a large solar array, because it might give you away?” Roeschmann says. “A wind turbine has a very, very small visual footprint from above. It might make sense to do that instead.”

Marsh, for his part, thinks his earliest customers might be beachgoers looking for a bit of electricity to power their good times in a high-wind environment. “My wife said, ‘Can this run a blender? So we can have a margarita on the beach?’ ” he says. “I’m like, ‘Yes!’ ” His homemade one-thousand-watt turbine prototype—an eight-by-eight-by-sixteen-inch aluminum box—loads easily in a car trunk or truck bed. Of course, you’d also have to haul and set up a blade assembly to attach the unit to—a long pole holding the fan blades—to enjoy that margarita. (The version Marsh has tested requires digging a small hole nearly three feet down into the sand, into which he plants a pole that extends more than 10 feet high with a fan between 4 and 6 feet in diameter at the top.) His three-thousand-watt prototype, on the other hand, is more than five times the size and much more difficult for a single person to lift.

Many of the other uses that Marsh imagines for his turbines are archetypically Texan—powering truck-mounted lights for night fishermen along the Gulf Coast, providing entertainment for football tailgaters, and even resurrecting abandoned well pumps in rural areas of the state. “Because my generator is self-regulating, I eventually could use the old-style fans that are up there and tie it into my generator and have it run a pump,” Marsh says of the classic Aermotor windmills that have fallen into disuse on many Texas ranches. “And it’d still look like it was old, except for the white or aluminum generator container up there.”

Of course, the largest potential market for small turbines is wind power generation that could be tied into the grid—setting up turbines on your roof or in your yard to reduce your electricity bill. The National Renewable Energy Laboratory estimated last year that the United States could profitably build 1,400 gigawatts of capacity from small wind turbines, which is equal to more than half of the country’s annual electricity consumption.

To power everything in your home (at least when the wind is blowing), you’d need more like five thousand watts, more than what any of Marsh’s existing prototypes can generate. He says it’s certainly feasible for him to eventually scale up to that size, but he estimates that the current return on investment for home wind generation is between ten and fifteen years. Plus, it still requires putting up with a lot of noise and vibration during high-wind events. (And the more wattage you hope to generate, the taller and larger your blade assembly typically needs to be.) He says that his Pirate Wind Turbines will be significantly more economical, but he’s not ready to make any specific predictions about how long it will take to recoup one’s investment via home energy savings.

Marsh’s target consumer price for a USA-built one-thousand-watt turbine is $1,800. He notes that a Chinese-made, one-thousand-watt turbine currently costs $1,300 on Amazon. But he argues that his price point is still a better bargain because many purchasers of the existing technology will eventually realize that they also have to buy an electronic brake for $800 to $1,000 extra.

Even if only the sorts of customers he refers to as ”preppers” adopt his wind turbines for home electricity generation, Marsh still sees intrinsic value in moving the technology forward. “I’m doing what I’m doing because I want something that works, and I want it to be quiet, and I don’t want the vibration,” he says. “The industry is just filled with junk, so I’m doing something about it.”

What really makes Marsh’s eyes light up is not, in the end, the idea of making millions of dollars or dotting the beaches of Padre Island with his machines. Instead, Marsh gets most visibly excited when discussing his next idea for a turbine-testing setup—a purchase he hopes will someday replace his modified truck.

“My simple wind tunnel idea—I’ve already looked into it—is to buy an air-fan boat, like you see in the swamps of the Mississippi, with the big engine and propeller,” he says, smiling broadly. “I’d like to own one of those swamp boats, just so I could hit my turbine with a one-hundred-mile-an-hour wind. I would love to build a homemade wind tunnel out of an old swamp buggy.”


TOPICS: Business/Economy; Military/Veterans; Outdoors; Society
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To: mikey_hates_everything

The blades on my wind turbine are designed to detach when rpm goes above a certain level😂. No need to dump current then.


21 posted on 09/06/2023 11:51:56 AM PDT by steve86 (Numquam accusatus, numquam ad curiam ibit, numquam ad carcerem™)
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To: steve86

Yeah. the water heater is 5KW, the range is 3KW, the dryer is 2KW, then each room has a (minimum) 1KW baseboard heater. Add in the lighting load and well:

5KW doesn’t go very far in an all electric home, FRiend...


22 posted on 09/06/2023 11:55:18 AM PDT by Don W (When blacks riot, neighborhoods and cities burn. When whites riot, nations and continents burn)
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To: Red Badger

Windmill makers solved this problem in the 19th century by simply turning the turbine away from the direction of the wind.


23 posted on 09/06/2023 12:01:06 PM PDT by Chad C. Mulligan
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To: Chad C. Mulligan

Installing a Reeves drive, as used in snowmobiles and ATVs, between the turbine and the generator would work, although it would lose some efficiency. The principle behind the Reeves drive was invented in the early 1800s, if memory serves. A variation would use a bicycle derailleur.

None of this solves the problem of getting power when there’s no wind.


24 posted on 09/06/2023 12:08:57 PM PDT by Chad C. Mulligan
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To: Yo-Yo

A Doubting Thomas here. Drag. The drag produced by the platform is drag, plus the drag of the blades, plus the most important fact- the energy required by the moving vehicle to rotate the generator is largest factor.

Even our modern day alternators rob the engine of horsepower ( energy), I would be surprised if all the drag and strain on the engine ( more gasoline required) would barely exceed the “ windmill” energy output.

https://thepowerfacts.com/how-much-power-is-needed-to-turn-an-alternator/


25 posted on 09/06/2023 1:05:04 PM PDT by delta7
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To: Wilderness Conservative

—> These things have been on the market for boaters

Serious problems for boaters in big winds. They can break apart and damage the s/v


26 posted on 09/06/2023 1:28:48 PM PDT by aMorePerfectUnion (Fraud vitiates everything)
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To: Chad C. Mulligan

Assuming the alternator is a permanent-magnet type, and it can stand the RPM, you just switch out one or more of the stator coils, the way the alternators on British motorcycles did in the ‘50s and ‘60s.

Or change their connection pattern from series to parallel.

The original Honda 750 Fours had a live field coil, they simply manipulated the field voltage to control output. Both the field and the stator were stationary, so there was no RPM limit.


27 posted on 09/06/2023 1:46:16 PM PDT by Chad C. Mulligan
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To: Tell It Right
Can't the same be done by people who want to use small-scale wind turbines to make themselves a bit more energy self-reliant?

Isn't that bowing down and kissing the ass of the government that has successfully convinced the morons that wind power is more efficient than coal fueled electric plants?

28 posted on 09/06/2023 1:52:57 PM PDT by Hot Tabasco
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To: Tell It Right
I looked at solar power a few years ago. What I discovered is that the biggest problem is finding batteries at a reasonable price for a sufficiently useful amount of storage.

It appears Lithium Iron Phosphate is the way to go, but they aren't cheap, and you will spend more on batteries than the rest of the system put together.

29 posted on 09/06/2023 1:57:37 PM PDT by DiogenesLamp ("of parents owing allegiance to no other sovereignty.")
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To: Red Badger

I don’t actually grasp how this thing is beneficial. Could someone explain it in a few simple sentences?


30 posted on 09/06/2023 1:58:48 PM PDT by DiogenesLamp ("of parents owing allegiance to no other sovereignty.")
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To: DiogenesLamp

His three-thousand-watt prototype, on the other hand, is more than five times the size and much more difficult for a single person to lift.


31 posted on 09/06/2023 2:04:57 PM PDT by Vaduz (....)
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To: Hot Tabasco
Isn't that bowing down and kissing the ass of the government that has successfully convinced the morons that wind power is more efficient than coal fueled electric plants?

I can't speak for micro wind power owners. But for the solar power owners on FR we're not conceding anything of the sort. I believe coal, uranium, and natural gas are the best for powering the grid (with hydro power IMHO being good too, but that's about maxed out). And I believe natural gas is best for heating the home and cooking (we heat the home some here in Alabama, but obviously not as much as we consume energy for cooling). And I believe in most ways gasoline fueled ICE cars are better than EV's.

But, and this is very important to me and most of the few FReepers with solar: I can't mine my own coal. I can't drill my own natural gas. I can't drill and refine my own oil. If I want some level of self-efficiency with energy to reduce my family's dependency on over-regulated and over-restricted energy sources then I have to produce energy on my own in the only way that's feasible and practical to do it on a small scale for an individual home (at least in Alabama). And that's with decentralized solar (solar for me, not utility level solar making the grid dependent on solar like the Dims push). I can't blame someone for doing the research I did to implement decentralized wind power like I implemented decentralized solar power (assuming the person is in a situation and environment for doing so).

You and I are on the same side of the argument on how best to power the grid (coal, nuclear, maybe some natural gas) and what to do about gasoline prices (drill baby drill). Evidently the difference between you and me is I'm for taking the next step and each of us as individuals (families) doing what we can to be more self-reliant (including with energy) so that the government has less control over us. That's what I think about when I see articles like this about micro wind turbines or micro hydro turbines or residential solar panels. It's working for me to greatly reduce how much energy I buy from the traditional sources that the Dims control way too much.

32 posted on 09/06/2023 2:14:47 PM PDT by Tell It Right (1st Thessalonians 5:21 -- Put everything to the test, hold fast to that which is true.)
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To: DiogenesLamp
True that on batteries being a significant cost in home solar. All the more so with the solar tax credit artificially inflating the costs like other government "help" does in other industries.

I basically pay for my batteries with a HELOC I took out for my home energy project (solar equipment, added insulation, converted my two natural gas appliances to electric ones that are very efficient appliances). My HELOC payment plus small power bill were a hair more each month than what I was paying in year 2019 for power + natural gas (year 2019 IMHO is a good standard for energy prices since covid hadn't distorted energy prices). And the solar tax credit paid down a significant chunk of my HELOC, which made my HELOC payments go down to the point where my HELOC payment + power bill in year 2022 was even to what what I was paying for power + natural gas in year 2019. Yay! I had beaten 3 years of inflation! Further, if I stayed the course, as I slowly paid down the HELOC my HELOC payments would go down in future years, while the energy prices I avoided half of would go up. In other words, it's cost me less to save more, then the next year it'd cost me even less to save even more, etc. And this was with Phase I of my solar project, producing 58.5% of all the power we consumed in a year. But that wasn't as far as I wanted to take it if Phase I proved that the equipment and my analysis of solar in my area plus mine and my wife's power consumption habits were correct. So I did the data analysis (yay to my inverter having a good telemetry export recorded at 5-minute candles) and implemented Phase II last year. That included replacing my wife's car (which needed replacing anyway) with an EV, doubling my solar panels and inverter capacity, and tripling my battery storage. Last month was the 1-year anniversary of the upgrade and it's producing 82% of all the power we consume in a year, including charging the EV (by my estimate about 22K to 23K miles are charged at home of the total 26K miles we drove the first year).

So far the overall energy project has saved my cash flow (read: my retirement investments) a total of $1,900 more than it's cost me (expenses I didn't put into the HELOC). Now that the EV is part of the equation, I'm basing my gas and oil change savings off of 2019 prices too. Any time the overall energy costs ($75 power bill + HELOC payment + car payment) are more than what I was paying in year 2019 for power + natural gas + gasoline + monthly savings deposit for car repairs and replacement I take the difference from the HELOC. And when I get the tax credits (which I get 3 tax years for the EV and solar upgrade because the EV and solar tax credits are non-refundable, but the solar tax credit at least carries forward to future years) I use it to pay down the HELOC. At the point the EV is paid off 3 years from now I still will have saved my cash flow $6K more than the project cost me (assuming a reasonable 3% inflation rate of energy costs I'm avoiding in power, natural gas, and gasoline). After that, with no car payment, the savings skyrocket with my energy portion of my budget paying just a small power bill and an ever decreasing HELOC payment.

Admittedly, this was when we could get a loan with a low fixed interest rate.

33 posted on 09/06/2023 2:35:32 PM PDT by Tell It Right (1st Thessalonians 5:21 -- Put everything to the test, hold fast to that which is true.)
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To: delta7

I think he’s using the car to test his windmill output, not to generate usable energy but simply to test and gauge his equipment.


34 posted on 09/06/2023 2:35:55 PM PDT by muir_redwoods (Freedom isn't free, liberty isn't liberal and you'll never find anything Right on the Left)
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To: Paladin2

No problem. Get your E-Cat personal fusion generator ... any day now.


35 posted on 09/06/2023 2:40:18 PM PDT by RetiredTexasVet (Biden not only suffers fools and criminals, he appoints them to positions of responsibility. )
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To: DiogenesLamp

Solar energy is FREE!

YMMV....


36 posted on 09/06/2023 2:45:56 PM PDT by Paladin2
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To: DiogenesLamp

Solar energy is FREE!

YMMV....


37 posted on 09/06/2023 2:45:56 PM PDT by Paladin2
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To: DiogenesLamp
I don’t actually grasp how this thing is beneficial. Could someone explain it in a few simple sentences?

Look at it from a personal power production perspective to reduce how much power a person (or family) has to buy from the grid. That's what to think about when you see that it's about micro wind turbines (or micro water turbines, or residential solar). Another word to look for in this concept is "decentralized" as in "decentralized solar" like some of us FReepers with solar have to reduce how much power we buy from the grid to reduce how much the Dim's stupid energy policies impact our wallets. It's not about saving the world our powering the grid with so-called "clean energy". Devices like these don't put power onto the grid. This is about increasing a person's self-reliance.

And about what makes his invention special is, ostensibly, it handles wind gusts better. When the turbine creates power based on the expected wind speed for the area, the charge controller taking in that power isn't maxed out. But with excessive wind speeds a fixed propeller will generated more power than the charge controller can take in. So this guy (and the makers of the large scale wind turbines for grid power) try to account for that by having the wind turbines' propellers automatically change shape to reduce how fast the wind turns them when wind speeds exceed the usual amount. As to why that's the approach instead of just making the charge controller able to take more power anyway, I don't know. Maybe that'd be infeasible to do. (See my post # 10 on how we handle a similar problem with decentralized solar in a way that IMHO is cheap and doesn't add maintenance.)

38 posted on 09/06/2023 2:51:13 PM PDT by Tell It Right (1st Thessalonians 5:21 -- Put everything to the test, hold fast to that which is true.)
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To: Tell It Right
Sounds like you did well.
39 posted on 09/06/2023 2:51:17 PM PDT by DiogenesLamp ("of parents owing allegiance to no other sovereignty.")
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To: Tell It Right
So this guy (and the makers of the large scale wind turbines for grid power) try to account for that by having the wind turbines' propellers automatically change shape to reduce how fast the wind turns them when wind speeds exceed the usual amount.

I think someone came up with that idea around 1900.

But the primary problem with self sufficient energy systems for the home is the batteries. I forgot what the prices I was seeing was, but it was looking like I was going to have to spend between $5,000 to $10,000 dollars to get a decent battery system.

And then I had the worry of where I would put them so they didn't burn everything down if they caught on fire.

Still working on the idea, but a home energy system is a back burner project for me now.

40 posted on 09/06/2023 3:00:15 PM PDT by DiogenesLamp ("of parents owing allegiance to no other sovereignty.")
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