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Hydro/Wind/Wood/Geothermal And other types of alternative energy

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  #1  
Old 03-30-2013, 09:19 AM
Plowpoint Male Plowpoint is offline
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Default Wind Thermal

Chrisser had a great idea for Wind-Thermal, which is using wind to produce heat. In my home's case, I live on a hill and have plenty of wind, but really do not need electricity as much as I need warm water. My biggest consumer of electrcity is actually in producing warm water; for our domestic needs, for the sheep stock tanks, for the chicken coops, and for radiant floor heat. If I could produce hot water from the wind, I really would be in great shape.

My idea came from my knowledge of hydraulics. Whenever my tractor puts its hydraulic system into relief, the oil is shot through a very small orifice under heavy spring pressure. That makes the oil really hot, really fast. Under that theory I devised this idea for a wind-thermal idea.

If a windmill was connected to a piston and oil put inside, through the laws of hydraulics, the piston would drive a high volume of oil through a small orifice and produce high heat. That oil would then be pumped back into the top of the piston to be redriven down through the orifice in an endless cycle. Now if that piston chamber was surrounded by a tank of water, it would be heated by the oil continuously pumping through it, and that hot water could be pumped into the house or barn for various uses.

That is the simple version.

If more efficiency wanted to be added, a windmill could drive a swash plate that powered multiple pistons that created heat. In this way, you would not get a single stroke per revolution of the windmill, but rather multiple strokes through one revolution of the windmill.

The beauty is, the harder the wind blows, the more oil that is pumped producing more heat. A governor would need to be added only to prevent the wind mill blades from disintegrating from too high of a speed.

I have thought about this a lot over the years and really think it would work. It does not go against any laws of physics, hydraulics or thermal dynamics and thus should work.
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Old 04-11-2013, 02:11 AM
SubDan Male SubDan is offline
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My only concerns in generating heat in this manner is flow rate and pressure. What is the inlet water temperature and expected flow rate. I have used chilled water cooling for hydraulic systems in the past but they were 100hp and larger systems. Please keep the post up-to-date when you start testing.
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Old 04-13-2013, 09:19 AM
Plowpoint Male Plowpoint is offline
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What I heat is dependent upon what the wind-thermal unit produces for btu's. In doing a detailed calculation of my home, I need a 65,000 btu heating appliance for my heat loss. I would have to size the wind-thermal unit to meet that (if possible) but if I could, I would be able to heat my radiant floor with it.

What the target temperature is varies with the temperature outside of course, but with a flow of 1/4 gallon per minute, I get a drop of 15 degrees in my floor upon the return, which is ideal. My target temperature varies between 76 degrees and 100 degrees, so if we average it out and say for most of the heating system I need 85 degree water flowing through my concrete slab, at a 15 degree loss at the return, my input water temperature (on average) would be 70 degrees.

More than likely, I would not hook it up "direct drive" so to speak to my radiant floor heat. I would just loop the wind-thermal unit to my main boiler loop so that when the wind is not blowing, the boiler would automatically compensate. In that role, the wind-thermal unit would just be putting extra btu's into the main boiler loops so that the boiler would not come on as often. The mixing pump would then distribute that hot water in the proper amounts to the floor as needed, just as it does with my propane boiler now.

If I did that, it would mean the incoming water would be 100 degrees. I say that because the propane boiler comes on at that temp and shuts off at 150 degrees. Flow rate could be variable, but I am thinking 1/4 to 1/2 gallon a minute would be a good place to start.
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Old 04-19-2013, 11:49 PM
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Compressing a fluid increases the temp of the fluid. Think of it as dissipating the kinetic energy of the piston as thermal energy in the fluid. The problem is, using a wind mill to move a piston against dense water is probably less efficient than using it to turn an armature in a generator. And there's the problem of fluid volume, flow rate and total heat content: a cup of boiling water may register 212deg, but a swimming pool of water at 40deg contains more heat. A wind mill may not be able to heat enough water fast enough to be effective as a heating method. 65,0000 btu equals 19kW-hrs, so, allowing for inefficiencies in converting the mechanical energy into water heat, you'd need a pretty big system to supply that.
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Old 04-20-2013, 08:42 AM
Plowpoint Male Plowpoint is offline
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Thanks for doing the math on that for me.

I should have suspected it; wind is just junk energy and is unusable. I say that because despite being in a high wind area, everyone that has tried wind power has learned how inefficient it is.

I could scale the system down and possibly heat three areas that are currently done with electricity; a high proposition here in Maine since we have the highest electric rates in the country. Rather then trying to heat an entire home, I could use the same wind-thermal concept to heat my lambing pens, or my chicken coop, or my stock tank. All currently use electricity for heat.

But while wind is relatively inexpensive, creating the device to harness it would be riddled with challenges and expense. Probably in the long run it would just be easier to pay for the electricity, or use other proven methods to obtain the same heat.

Thanks again for doing the math though it just makes my anger towards wind all that much greater.
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Old 04-21-2013, 12:16 AM
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I've been following wind & PV electricity generation since the 60s. Seems like "free energy" but it isn't. They always seem to keep the costs of apparatus just too high to be economically efficient, even if you do your own labor.

Advocates of alternative energy always ignore the cost of lost investment potential on the money spent up front for the sytems: instead of buying wind turbines or PV units, maybe with borrowed money, making it even more expensive, that capital invested in something safe like a Dow fund (the Dow has returned 5%+ for the past century or so) would turn each $1000 dollars into $2650 after 20 yrs, the lifetime of most alternative systems. That $20,000 system has cost them $53,000 in lost investment returns after 20 yrs. Would they have spent that much on grid power?

Living in Maine, you must have access to plenty of waste brush, trees, etc. Have you considered using an old engine fueled by wood gas to generate electricity (and heat from the cooling system)? http://www.gengas.nu/byggbes/index.shtml Free fuel; very reliable energy source.
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Old 04-21-2013, 07:04 AM
Plowpoint Male Plowpoint is offline
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Yep, you certainly hit the nail on the head in terms of Return on Investment and Purchase Cost. My Uncle has a grid-based bought wind mill and it is a total waste of money. Initial cost was 17,000 and he saves about $65 dollars in electricity a month, which at that rate will take him about 27 years to pay off, at which he will long be dead!

Even the huge win turbines going up around the state are big losers. If it was not for the green credits they get from the big coal powered plants in the mid-west, they would not have a favorable return on investment either!

I have reduced my electrical consumption greatly, but not with alternative methods of producing it, but rather by using more efficient fuel choices. For instance our cook stove is propane, as is our clothes dryer, and soon our domestic hot water. The meager amount of propane used, compared to how fast and easily they heat up is actually staggering in comparison to using electricity to do the same thing.

I ran into this issue a few years ago when considering compost heat. I know from being a farmer that our silage piles contain a huge amount of heat, staying 120 degrees or so all winter long, and if I ran pipes through a pile of compost, it would heat my radiant floor. I did tons of research and found other people are doing this, so it is possible, but here is the thing; while doable, it would take less time and effort to just go out and harvest the 4 cords of firewood I need to heat my home with a wood stove then it would be to go through the expense and trouble to use compost heat.
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Old 08-27-2013, 01:15 PM
Post_Oakie Male Post_Oakie is offline
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Plowpoint, are you not running the sawmill these days? I figured you'd have plenty of slabs. Ground source heat pump might make good sense, whether powered by a wind turbine or conventional electricity. The Lost Investment Potential analysis is valid, but assumes that the price of electricity will not increase significantly. If you are preparing for major changes, you need to adjust your thinking accordingly. For payback, solar thermal is hard to beat, but might not be as attractive in Maine as it is here in Missouri.
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