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Mining with renewable energy.

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stan.distortion

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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.
 
I'd love to know where to start. I have never actually moved in this direction because I suppose it might demand quite a big investment. Also, I have never been sure if it would be a lucrative activity.

But it has always attracted my attention, not only mining, but better, mining using renewable energy sources.

I have got the perfect place for it, a house in a city in the Northeast of Brazil (Natal), sunny and windy 365 days/year.

When I retire, I'll possibly set something like this:

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Sounds like an ideal spot :) As far as I can see the panels in the second pic are solar heating though, the best move you can make in terms of bang for your buck but not much good for running miners ;) You wouldn't get a whole lot from a turbine that size either but they're well worth experimenting with because they've often a far better return on investment time than bigger units and energy storage is far more manageable. That's an area often overlooked, you can have a serious surplus of power in high winds and even dumping it can be problematic and adequate storage can cost way more than the turbine its self.

I've very little experience with solar, not much sun here in Ireland but I'd imagine its the best thing to start off with in Brazil, the tech race is advancing pretty fast with panels and its easy to feel left behind but its simple to figure out how long they'll take to pay for themselves and so long as space isn't really tight then that's all that really matters. A bit jealous now, turning cold here at the mo and some sun would be nice :)
 
Thanks for the ping on this Splawik.

I have a 10KW solar grid tied system and about 6TH of miners undervolted to run a 3TH. The solar system feeds into the electric grid and there is no direct connection to the miners. The decision to add solar and miners was made independently. Here is how you would decide.
For Mining:
Low electric rates are the main requirement for a profitable mining operation. Right now about 8 cents/kwhr electricity will give you about 1 year return on a mining investment. And even then, you would need to keep mining or sell your equipment to get be ahead. It really isn't profitable except for those that live by hydroelectric plants with 5 cents/kwhr electricity. Right now, I am converting my BFL Monarch miners to heat water when my solar water system doesn't keep up in winter. It really isn't profitable for me now without getting creative.

For Solar:
There are incentives by the utility, state, and federal in the US to install solar. We have a 30% federal rebate and a utility rebate that is about 10% of the cost. So first check what incentives are available. High electric rates give a better return with solar. And in warmer climates you get more solar energy. For our commercial customers our systems return about a 5 year payback and residential customers closer to 8 years. This is for Minnesota(coldest climate in the US) with about 10-14 cents/kwhr electricity. The decision to go solar is a long term investment, and you will want a local installer to help you with the details.
 
Ever look into running everything from DC? We're limited to supplying a max of 5kw/h to the grid for domestic setups here and the rates are atrocious, paying 0.18 euro per kw/h and receiving 0.09 so using the grid instead of batteries makes little sense plus the grid tie inverter specs are different to the rest of europe and its about 5k euro for an inverter. I guess running off DC for regular PC hardware could be tricky but ASIC hardware should be simple enough.
 
I'd love to know where to start. I have never actually moved in this direction because I suppose it might demand quite a big investment. Also, I have never been sure if it would be a lucrative activity.

But it has always attracted my attention, not only mining, but better, mining using renewable energy sources.

I have got the perfect place for it, a house in a city in the Northeast of Brazil (Natal), sunny and windy 365 days/year.

When I retire, I'll possibly set something like this:
My suggestion would be to skip the wind generator. Wind generators will require maintenance and replacing parts, and typically, this is a lot more that what the manufacture claims.

Solar is the way to go. Solar water heating in your area, is going to give you a lot of hot water for just 1 or two collectors. I would suggest considering building these yourself. Check out this site for details on building your own:
www.builditsolar.com

For electric, you can get photovoltaic panels. Your payback will depend on your electric rate and if they pay you for the energy you produce. We have net metering here: utility pays you the same rate for what you produce as what you use. Also check for any incentives. You are right about this being a big investment. But if there are incentives, it may be attractive. There are also companies that lease solar systems and offer 10% reduction in your bill. It is better to pay for a system because you get that invested value back when you sell your house, but it is an option.
 
Ever look into running everything from DC? We're limited to supplying a max of 5kw/h to the grid for domestic setups here and the rates are atrocious, paying 0.18 euro per kw/h and receiving 0.09 so using the grid instead of batteries makes little sense plus the grid tie inverter specs are different to the rest of europe and its about 5k euro for an inverter. I guess running off DC for regular PC hardware could be tricky but ASIC hardware should be simple enough.
You can get battery backup inverters for your situation. Basically, the solar will offset what you are using. If it has extra it charges the batteries. If you are using more power it pulls from the batteries. Basically, you save that .18 euro power. We don't deal with this much here, but check out these sites.
http://www.teslamotors.com/powerwall
http://outbackpower.com

As for running DC, no. The ASIC miners I use take about 4000W of power. A DC cable to power that would be handling over 300 amps and would be a thick 2/0 cable. Plus the power needs to be regulated and it ends up costing a lot to get regulated DC from batteries.
 
You can get battery backup inverters for your situation. Basically, the solar will offset what you are using. If it has extra it charges the batteries. If you are using more power it pulls from the batteries. Basically, you save that .18 euro power. We don't deal with this much here, but check out these sites.
http://www.teslamotors.com/powerwall
http://outbackpower.com

Cheers. I'd had a look at the Tesla ones before and wasn't that impressed, very highly priced in terms of capacity but good for residential setups, clean and compact and ofc there's the branding. Hadn't come across Outback Power before but they look more tailored to the application, will add up their rates in a while. One thing nice with the Tesla systems is they'll raise public awareness, the erratic nature of renewables really screw up the grids distribution so the more storage the better, they make a hell of a lot of sense when cheap rate electricity is available and the more storage in use the more chance power companies will bring in dynamic rates and then folks can make really big savings.

Your 10Kw setup, what sort of area does that cover and what does its average output during the day?
 
Solar really matches the AC load of buildings. It is almost a perfect match, so I don't see the problems you see with erratic power. Of course, that is more of a neighborhood level. If you want to run offgrid, batteries are needed and usually a generator too.

The Tesla unit is expensive and personally, don't see much benefit. But who knows. The outback units will also cost about $5K vs $2.5K for a standard inverter.

I have 230W panels on my roof, but newer panels are 260W, so a newer system will use less space. I have 43 panels and each panel is 39" x 60"(1m x 1.5m). They pretty much cover my entire roof. If I am not mining, I will get $50-100 checks back from the utility in the summer and pay $80-100 in winter. Pretty much nets out my average $80 bill each month.
 
Solar really matches the AC load of buildings...
How do you calculate the perfect angle, I appreciate most people just stick them flat on the roof as is, I have often seen solar placed in what appears to be the wrong angles to get the most sun light, so what is the formula to calculate from your latitude and time of year, the very best optimum placement ?
 
I mean erratic for the grid its self, not so bad for solar but wind really messes it up and makes loads very hard to plan. The head of the electricity board here made a laughing stock of himself a few years ago when he said wind power was "the wrong type of electricity", I guess he was just doing the best he could when explaining it briefly to non-technical folks :)

Sounds like it was well worth the investment for you :) I was wondering about the figures because its hard to find anything consistent, the manufacturers tend to be a little over-optimistic and there's a lot of outdated data but even then its regional, as far as I can see Ireland averages about 0.4kwh/day per square meter but that data's from about 5 years ago.
 
How do you calculate the perfect angle, I appreciate most people just stick them flat on the roof as is, I have often seen solar placed in what appears to be the wrong angles to get the most sun light, so what is the formula to calculate from your latitude and time of year, the very best optimum placement ?
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.
http://pvwatts.nrel.gov/
 
I mean erratic for the grid its self, not so bad for solar but wind really messes it up and makes loads very hard to plan. The head of the electricity board here made a laughing stock of himself a few years ago when he said wind power was "the wrong type of electricity", I guess he was just doing the best he could when explaining it briefly to non-technical folks :)

Sounds like it was well worth the investment for you :) I was wondering about the figures because its hard to find anything consistent, the manufacturers tend to be a little over-optimistic and there's a lot of outdated data but even then its regional, as far as I can see Ireland averages about 0.4kwh/day per square meter but that data's from about 5 years ago.
Utilities look at renewable energy as an added pain to deal with. They also lose revenue as more people add solar/wind. So they are usually negative about renewable energy. Funny that he mispoke and got called out on it. See my link above to answer your question.
 
...
Here is a good site to calculate watts and power output specific to your location and angle the sun faces.
http://pvwatts.nrel.gov/

Impressive, thanks. Really wasn't expecting that to work for Ireland but it came up with very detailed info.

Yes, the supply board here is making things very difficult individuals trying to get started with it, quite accommodating to foreign investors setting up big operations though... :/
 
Just read something that reminded me of something I meant to ask. Solarminer, do you use DC to DC converters or know if they're in common use? I mean for turning a variable output voltage into a fixed voltage suitable for batteries? Not sure if it comes up with solar much but with wind the output range is so variable that windings in permanent magnet alternators can't really be spec'd correctly for fixed voltage, DC to DC converters would solve that but I've very rarely heard of anyone using them.
Cheers.
 
Just read something that reminded me of something I meant to ask. Solarminer, do you use DC to DC converters or know if they're in common use? I mean for turning a variable output voltage into a fixed voltage suitable for batteries? Not sure if it comes up with solar much but with wind the output range is so variable that windings in permanent magnet alternators can't really be spec'd correctly for fixed voltage, DC to DC converters would solve that but I've very rarely heard of anyone using them.
Cheers.
For off-grid systems we do use the solar panels to charge batteries. Solar panels are 18V for 12V batteries and 30V for 24V batteries. You can just hook the panels up to the batteries directly, but you do risk overcharging the batteries. So we use charge controllers. The simple version just shuts off the panel power when the batteries hit a certain voltage. There are MPPT charge controllers that accept a wide voltage(30-150V) so you can have several panels in series. They step this down to the battery voltage and also stop charging when full.

Wind turbines generate AC. The frequency of the voltage is tied to have fast the blades spin and the voltage is tie to how fast blades spin and how much load is on the output. With high speed switching devices(IGBTs an MOSFETs) this is getting easier to control. I think this is how the voltage actually gets transformed to something useful.
Wind --> AC --> Rectified to DC --> Inverted to AC Grid voltage
Or
Wind --> AC --> Rectified to DC --> MPPT controller to battery voltage
 
I'll definitely research this well. It's a very interesting subject. And I tend to feel attracted to this type of activity.
 
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