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Mining with renewable energy.

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I'll definitely research this well. It's a very interesting subject. And I tend to feel attracted to this type of activity.

Nice :) The turbines are something I've been working on for a while and it's been interesting, modern designs have an almost unbelievable amount of scope for improvement and are at least an order of magnitude overpriced. I've been very lazy with it lately though but hopefully the weather turning bad will get me motivated again, the intention is open designs using mostly off the shelf parts an hopefully a network developing for sales, design tracking, operation monitoring... and accounting. Crypto of some sort will come into it if it gets that far, what I have in mind should allow installation to fund its self (ROI time is a key target), they're effectively money printing machines and any serious design should be able to stand over that and base its own income on it.

Anyway, I'll be quiet, less talk and more action :) Cheers solarminer, MPPT charge controllers is what I was looking for, sub-ether should be able to knock one together no problem ;)
 
Nice :)
Anyway, I'll be quiet, less talk and more action :) Cheers solarminer, MPPT charge controllers is what I was looking for, sub-ether should be able to knock one together no problem ;)
What about alternators from trucks, use mass produced none specialist parts, no neodymium magnets makes for less efficiency but can build more for same price, $132 dollars for 250 amp, 12 volts, making 3 kilowatts.
http://www.amazon.com/gp/product/B0..._m=ATVPDKIKX0DER&pf_rd_r=0SA2TCFEG8F7JQE9MYZ6

If you want the equivalent wind turbine generator its more like $400 for 2000 watts,
http://www.ebay.com/itm/Freedom-II-...hash=item43cabcf9e8:m:m3-CaIIJ84-5u_zN89F-aLQ
 
Speed ranges are all wrong, alternators are an absolute bargain otherwise, cheap, compact and efficient but they need to run about 5 to 10 times faster than an impeller sized to match their output. That sounds like a simple matter of adding a gearbox but it doesn't work out that simple in practice as gusts and inertia create very high shock loads. Those loads are way higher than you'd expect, toothed belt drives seem well suited but in practice they have to be speced to at least 3 times the calculated load and that puts the efficiency way down at regular operating speeds in the 10 to 20 mph range.

That's why swapping out the field wound rotor for a permanent magnet type is popular as it allows good output with direct drive but the windings are still a limiting factor, the power available rises exponentially with wind speed so something sized to stay within a 2kw limit in 50mph gusts only puts out a measly 60 watts at 15mph and if it gets hit by a 60mph gust then it spikes up to 4kw. That's where the variable voltage comes in, you'd be very lucky to be producing enough volts to charge a battery with that at 15mph and if you where limited to 18v at 60mph that's 250 amps, double the alternators rated output and the magic smoke will escape but alternator winding insulation handles 200v just fine and at 125 amps that's 25kw, plenty of head room without stressing anything and you can step up the low output voltage at low speeds.

Another option is to use a gearbox with torque limiting, a clutch to match the rating. I've not gone down that route so far as it has a lot of hazards, friction clutches wouldn't be consistent through wet and dry conditions, static friction is unpredictable and even if all that works out ok you'd have to dissipate several kilowatts in gale force winds which opens up another can of worms. Wet clutches would be the obvious way to go but then all your cost savings from using alternators get swallowed up and you'd be better of making an alternator suited to purpose.

Commercial turbines get around those issues by putting the brakes on at around 25mph and weathering out the storm. That's where all the videos of turbines on fire come from on youtube, worn brakes trying to dissipate several hundred kilowatts or even worse, worn out brakes failing and runaway turbines breaking apart. Seems crazy to me that the state of the art is something so fragile, high winds are where the really juicy outputs come from and capturing and storing that is the primary consideration with optimisation to make use of low winds secondary. It's doable but for now the state of the art has a long way to go.
 
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I've little experience with mining but a fair amount with renewables, mainly wind power and storage methods and always interested in sharing what I've learned over the years and learning more. Anyone using renewables for there setups? I'd be interested in hearing some of the pitfalls and experiences. Cheers.
Is a solar generator the best option to run a miner?
setting up a wind power generator is too much costly.
 
Ah, perfect angle...Sounds like you want a tracker. There are ideal angles, but then the real world comes in and says, the house faces here....make it work. If you have a flat roof, a ballasted racking system is typically 10 degrees, to put minimal weight on the roof. Residential, we are doing flush mounts on E/W and S sides. We don't put panels on north facing roofs, it just won't payoff. But we do run numbers based on where we 'can' put panels and then the customer decides if they want to go forward.

Here is a good site to calculate watts and power output specific to your location and angle the sun faces.
Good Idea
 
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