My journey to mining bitcoin from electricity created by the sun began last year on a mountain in Tennessee. At the time, my family was living off grid, exploring what it was like to take a step out of the regularly scheduled societal program and into a life of greater connection to the natural world and the people around us. We were living well with the sun as our source of electricity. So well, in fact, that there were many days that our batteries were topped off well before noon, which meant that our solar panels were capable of harvesting much more energy than we needed. I’d been hearing that bitcoin miners are really good at soaking up and monetizing excess energy, so I took a look at our system’s capacity and the miner options available. I discovered that Bitmain’s S9 miner was plug and play ready for my application, and it only cost $125. It was perfect as a low risk way to learn more about home mining and an easy way to test what it was like to mine on solar. I started plugging in the miner on sunny days after the batteries had reached full charge and it worked! I was turning the extra solar capacity into hard money. I was hooked and began dreaming of ways to optimize the system. Before long, I discovered an online community of home miners who were tinkering with all sorts of interesting ways to use miners to add value to their lives. In particular, I was intrigued by the work of Dirtyshotya from 100acresranch, who builds a tuner that allows a modified S19 series miner to run on 12v dc current straight from solar panels. This increases efficiency by eliminating the AC-DC power supply miners require when running from AC power sources. I purchased a tuner box from Dirty in November and began assembling the necessary components to build a completely off-grid solar mine. This week marked the maiden voyage of the system. As with any project that pushes the boundaries of what has previously been done, the road has been bumpy and winding. What follows is my attempt to get into writing the process, challenges, and successes of this project, both as a reference for future me and as inspiration and information to anyone who is curious about mining bitcoin with solar.
Before embarking on this project, I identified the following goals:
  1. To invest capital in energy independence and resilience.
  2. To expand my experiential capital in both solar systems and bitcoin mining.
  3. To setup a relatively passive income stream that reduces the ROI of the solar system.
  4. To harvest the heat from the miner to supplement home space heating.
I don’t currently live in a home that I’m able to add a solar system to, so I had to get creative. Fortunately, I found a family member who was willing to host the system in exchange for the supplemental heat from the miner. I have designed it so we can move it when we move to property where we have more space. The system is an asset that should bear fruit for decades.
The system is composed of the following components:
  1. Solar panels. Due to the design, 12v panels are necessary for maximum utilization of electricity produced. Technically, higher voltage panels will work, but they will be limited to a fraction of their maximum output because the miner requires 12v supply. 12v panels are more difficult to find. I got mine on eBay. I started with 3 Kw of capacity, which is around the maximum draw of my miner. This doesn’t mean the panels will produce 3 kW. We’ll get to that in a bit.
  2. Miner. Currently the firmware for the tuner supports Bitmain’s S19 series miners. I went with a j Pro 100Th machine.
  3. Solar tuner box. This is where the magic happens, adjusting the power sent to the miner based on what’s available from the panels and batteries.
  4. Batteries. 400ah of 12v lithium.
  5. Racking. I spent a lot of time putting together racking that was as cost effective as possible while meeting aesthetic and functional needs.
  6. Wiring, fuses, breakers, connectors. Due to the length of my runs, this required upsizing my wire.
Challenges in setting up the system:
  1. Panel placement. The roof I have access to faces east/west. This is not ideal. After careful consideration, I decided to place panels on each slope of the roof. My hope was to capture more hours of sun rather than focussing on peak power production. The jury is still out on whether this was a good idea.
  2. Wire run. Low voltage systems do best with short wire runs because of the expense of running wire gauges that are large enough to safely carry the amps the panels produce. The constraints of my system required wire runs of up to 45ft., which meant I had to upsize my wire gauge. This was expensive.
  3. Setting up the tuner box. This was mostly due to my limited technical knowledge. I was learning how to setup and operate a solar system, a bitcoin miner, and the tuner all at the same time. There’s a learning curve. I spent a couple of days foiled by a bad sd card. Slow and steady wins the race.
After running the system for a few days, some things are becoming apparent:
  1. The solar panels seem to be the limiting factor right now. In full sun they harvest around 750w, which is 25% of their rated maximum. My current hypothesis is that panel placement is largely to blame. The panels are flat on the roof, facing east and west. I knew this wasn’t ideal, but it seems to be even less so than I hoped. The next step is to try tilting the panels south as much as I can. Production should improve as we enter the summer months and the earth’s axis shifts to bring the sun higher in the sky, striking the panels more directly. I will need to make improvements if I expect to hash over the winter. There is enough space on current racking to add another panel or two, so that is another option for adding watts.
  2. Current battery capacity will only extend runtime marginally. It works well if the sun is momentarily obstructed by clouds, but if I want extended runtimes when the sun is down I’ll need to add batteries.
  3. Turning extra electricity into heat and BTC is fun! I see lots of potential to keep tweaking the system for maximum efficiency.
Questions? Ask away. Comments? Send’em over.
Very interesting. We've been considering rooftop solar for our house and I'm still thinking through getting a miner.
We have a decent roof for solar, although most of it is east/west. I was thinking of starting relatively small and just installing panels on the south facing portions of our roof.
I'll probably wait on the miner until next fall. when the "waste" heat will be useful for us.
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I have been using an S9 as a space heater all winter and loving it. Now I'm thinking of ways I can put it to use in the warmer months. One idea is a food dehydrator.
I thought that east/west would work well enough, as my panels are still in unobstructed sunlight. I'm discovering that angle toward the sun makes a huge difference as well. My next step is tilting the panels toward the sun. I'll post updates with what I learn.
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83 sats \ 3 replies \ @OT 15 Mar
How do you deal with the noise? Is the S9 in some kind of container?
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I replaced the power supply fan with a quieter one from Noctua and underclock the s9 to 900 watts. If I want it quieter I can underclock it further or replace the miner fans with Noctua fans, but so far that is unnecessary.
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21 sats \ 1 reply \ @OT 15 Mar
So the noise doesn't bother you or your family?
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No, it's about as loud as our air purifier on its medium setting. Just a gentle white noise in the background.
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When I will step into phase two of my citadel, I will come back to you with more questions about setup a mining rig. I am planning to build a micro hydro in my homesteading place.
For the moment, I just bookmark this post and will keep in mind to ask you more. Thank you for the detailed guide!
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Awesome. Always happy to share what I've learned. Hydro is a dream of mine. Maybe someday you can help with my hydro questions!
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Very cool stuff. Saw this on Nostr and glad you posted it here — now I can add it to my “Best of Stacker News” for March. Would be nice if there were some pics in the mix.
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I tried to add some pics. They didn't show up. Not sure what went wrong. I'll do some more digging and add them when I figure it out.
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@ek wanna help a newbie understand the mechanics of posting pics with markdown in SN?
For me at least, the icon with the picture symbol and plus sign works fine and then search for the image in my folders.
Essentially I guess SN is acting as host at that point. My other blog I had to pay for that ability (to drag in images). If I wanted images at first I had to host elsewhere and then paste the markdown link
Sounds good. Saw your comment with the pics. 🤙
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I'm pretty bullish on mini-miners + solar. In my ideal world, when you buy your solar system it includes a mini-miner to utilize excess capacity.
This could be a big boom to the solar panel companies as they would probably run the mining pool. Maybe this also reduces acquisition cost of solar systems as you will be generating revenue for them forever....
The public markets would love this idea as its highly invest-able. I hope it happens...
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That's similar to how I'm thinking about it. The resilience afforded by supplying your own electricity is wonderful. Large scale solar doesn't make sense to me. Small scale, absolutely.
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Solar energy is legit and usable?
It’s not propaganda?
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I think it is legit and usable on a small scale. I loved living on solar. We lacked nothing and had an abundance of energy many days.
Large scale and government subsidized I think it's a shitcoin.
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Good to know
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I am very curious to see the components that make up your setup. I run 6 s19 miners off of solar but I am using just the standard 240v power supplies. I have not got into the 12v DC mods yet. On the solar side it seems like it would be challenging with loew voltages. I use all 48v battery setups and high voltage solar runs to keep wire size and voltage drops down. Here is a a little video I made if anyone in interested. Thanks for the post.
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I watched your video! Love to see what you've done. Are you turning the miners on and off manually?
The low voltage is definitely a challenge. My furthest wire run is 45ft and I had to spend quite a bit on wire that could handle the runs. Thankfully it's a one time cost. I'm still gathering data to see what my efficiency numbers will be, but Dirty says he's achieved as low as 16w/Th on a j pro. Those power supplies do eat up some watts.
I don't think that direct dc is the best solution for all applications, but it is pretty cool to see the miner tuning it's power draw to what the panels are producing in real time.
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We should de-cenrtalized energy as we did with Bitcoin. F the grid it is a big waste. Every home should have its own energy source generator (depending where you live). An independent source. In case yours fail, a neighbor can help you with his until you get back on. GE back in the day proposed hydrogen generators on your front lawn, but they stopped that movement (because it made too much sense) I think. lol. For some it would be solar, for others maybe hydro or wind or combination of them. Pumped hydro-storage is big as well if you live next to the river and can use natural flow. Solar pumps during the day and hydro turbine at night.. So many opportunities. Buy you are on the right track @arealpeacemonger
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We're thinking along the same lines. A decentralized grid is a resilient grid.
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Have you calculated the ROI? According to some online calculators, an S19 will earn about $11 USD a day, if running 100% and with zero electricity cost. I assume you're way less than that and that amount will get reduced every 2 weeks with the difficulty adjustment (also it will be cut in half in about a month).
How much are you spending on hardware for this setup?
Also, remember you can just buy Bitcoin now with the USD you're buying hardware with. In fact, the $125 you bought the S19 with back in November would be worth about $225 right now. I doubt you'll ever see $100 profit with this mining setup.
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You're right that, purely in USD terms I would come out ahead just purchasing BTC.
My considerations also take into account increasing my experiential capital, investing in energy resilience and abundance for my family, the value of the heat produced by the miner, and satisfaction I get from participation in the network.
The s9 is used as a space heater in a cool room in our house, so the BTC mined is essentially a rebate on power that would've otherwise been consumed by a resistive heater.
The short answer is, I don't need it to ROI in a certain amount of time. The miner is always available to turn excess electricity into BTC and heat. If I want to use the electricity the system produces for other tasks, the miner simply ramps down until there's extra electricity that needs a consumer.
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Very cool project. I would love some pics of the setup.
Also, Have you used the s9 in place of the s19? Maybe the s9 will work with your solar and batteries better?
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I tried to upload pics, but haven't figured it out yet. There are some pics on nostr here: https://primal.net/e/note1v3ean329z69h3mhgqjzlcf8n0afjj2epdmzn7v03r9ema8rqwf4sjrjjk2
As the system is currently configured the s19 is mining at around 20Th, so significantly more than my s9 hashes. I'm hearing from folks that tilting the panels south should help increase production. I'll post again when there's more data.
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You can upload pics easily if you click on the picture icon in the top right corner of the write/preview window.
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Got it. I was trying to upload an unsupported file format.
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When you said "solar system" I thought you meant the sun and the 9 (yes, NINE) planets around it in our general vicinity of space.
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20 sats \ 0 replies \ @OT 15 Mar
Thanks for sharing!
I'm thinking of getting into small home mining when we move later this year
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Impressive work!
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0 sats \ 0 replies \ @rtr 22 Apr
I'm interested to reading a full log of this complete with pictures. I'm also mulling over the idea of mining using solar panels so I'm trying to read as much as I can about the topic.
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Very cool! Thank you for sharing!
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The solar panels seem to be the limiting factor right now. In full sun they harvest around 750w, which is 25% of their rated maximum
The amount of power is partially based on intensity (which you don't control) and partially based on angle of incidence (which you only control in some scenarios). 90 degree incidence is ideal (it is a cosine function).
Some people build robotic systems that actually track the sun but they are complex and not cheap. I've dabbled in this but it'd be interesting to see if there's different strategies on optimizing your output more.
I had not thought about just cutting out the AC and going straight to DC. I am curious if you have any data on about how much efficiency you saved.
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I've been working on improving the angle of incidence. Results so far are greatly improved. I'll share more here when I have more data.
I don't yet have data on efficiency gains from going direct-dc, but Dirty from 100acresranch says he generally sees between 16-25 j/Th on a jPro. Again, I'll share what I'm seeing when I get the panel angle optimized.
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says he generally sees between 16-25 j/Th on a jPro
What does this mean in the overall picture of efficiency? I'm an EE but haven't really played with mining just yet.
Even really good AC to DC converters will lose you 8-10% and state of the art is probably like 3-5% under perfect conditions. I wonder if commercial miners will get on this tip and invest in DC microgrids
Got a link to the solar tuner work that Dirtyshotya from 100acresranch did? I'm coming up blank when I'm searching.
I'd also appreciate some links to the 12v mods of the Antminer!
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100acresranch.com is the website. He's active on TG and I think he's on X as well. He's been very responsive and helpful getting the tuner setup.
I removed the power supply and added a Loki board from Pivotal Pleb Tech (pivotalpleb.com) to the control board before installing it in the tuner box. Pivotal Pleb has a detailed guide on their site for installing the Loki, which can also be used to allow a single s19 hashboard to be powered from 120v AC.
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Great project 👏 keep up with it 💪
and I wish you luck with your endeavor 👏
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Love resiliencemaxxing infrastructure
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It's kind of a rush.
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Great first post.
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Thank you so much. I'm also planning to plant a solar panel on the roof. Bookmarked it, this will be a real help for me
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Glad this is helpful! I hear a lot of fud around mining on solar, so I'm hoping that sharing what I'm learning will help inspire other folks to give it a try.
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