Right now Antminer S9 in decent condition is available locally. I have some, but considering getting more. I am saving up for a M30S or S17 running somewhere around 40 W/Th. Used S17 prices seems to hover around 55 USD per Th and Whatsminer about 80 USD (but warranty included).

S9 is about 20 USD per Th.

Trying to use braiins insight to make a decision.

Given 2 years investment horizon:
Setup 1:
50 % difficulty increase every year.
50 % price increase every year.
Hodl all.
6c power (2c power. 4c taxes and expenses)(expected to stay at same level in next years)

Scenario 1: Buy 6x S9: 1800 USD
Hashrate: 90 Th
Power: 7200 W

@24 months: 0.211 BTC
Power cost: 7560 USD power cost
Average cost of production 36294 USD per BTC.
Net profit: 7600, IRR =940%

Scenario 2: Buy 1x S17 pro 59th: 3400 USD
Hashrate: 90 Th
Power: 2900 W

@24 months: 0.139 BTC
Power cost: 2424 USD
Average cost of production 17604 USD per BTC.
Net profit: 8800 USD, IRR=490%


Different setup:
Setup 2:
50 % difficulty increase every year.
100 % price increase every year.

Scenario 1 with S9 now :
@24 months: 0.211 BTC
Net profit: 17200 USD, IRR =2000 %

Scenario 2 with S17 pro now:
@24 months: 0.139 BTC
Net profit: 16600 USD, IRR=950 %


Different setup:
Setup 3:
100 % difficulty increase every year.
50 % price increase.

Scenario 1 with S9s now:
@24 months: 0.169 BTC
Power cost: 7560 USD
Average cost of production 50337 USD per BTC.
Net profit: 3700 USD, IRR=640%

Scenario 2 with S17 pro now:
@24 months: 0.111 BTC
Power cost: 2424 USD
Average cost of production 24529 USD per BTC.
Net profit: 6300 USD, IRR=400%

I am planning to invest in mining equipment in the next years, but the prices right now for efficient gear are very high. Will we see another crypto winter? Will bitcoin spike and every piece of old mining gear suddenly be valuable again? Will difficulty growth outpace price growth? If mining becomes tough (and difficulty decreases) and bitcoin price increases - S9 investment will be better than saving for more efficient gear.

What are the best predictions with regard to difficulty development in the short term?

Hi,

Long time lurker, some GPU-mining previously - but recently got into asic mining.

Currently have some S9s controlled with aftermarket firmware running them at 900 W inhouse. Fan speed around 15-20% of maximum. Next up I plan to replace the fans with a duct-ventilator system, which I'm planning will be able to accommodate a bigger miner S17 or S19 in the future.

Noise suppressing boxes for the miners are popular, but as the fans are the root cause for the noise - fixing airflow or cooling by other means seems like a better solution.

My main motivation for investing in miners are seeing a return on the investment, and secondary using some of the excess heat to heat our house.

Electricity are stable slightly below 0.1 USD pr kWh all taxes paid, so the S9s are at the moment barely profitable - but they provide 'free' heat which comes in handy now during winter and most of the year.

My plan going forward with investments are:
1. Max out total power around 10 kW. Service to our house are 18 kW.
2. Keep noise to acceptable level, preferably below 30 dB inside house and having the garage somewhat not like the inside of a server room is a plus.
3. Recouperating some of the heat to provide heated water (and maybe a heated pool in the future).

I have extensive knowledge within electronics and SMT repair work, but I would like to have miners running rather than fixing them. But modifying them to run silent or longer between maintenance is no problem to undertake.

Immersion cooling seems like a no-brainer to reduce noise level. Watercooling seemed like a better solution at first, but it seems immersion is safer. As long as the immersion liquid is fine to handle and keep around the house (many are not).

Ideally I would like to run the liquid around 70 deg celsius and use a heat-exchanger (plate cooler) to heat the hot-water in our house. With regards to efficiency of the mining hardware, that does not seem to be a good idea with S19 series miners.

What, if any, mining equipment is known to thrive around 70-90 deg C? Basically 1 miner between 1-2kW will cover all hot water needs, so could possibly run separate baths for hot water heating.

Planning to invest around 10k USD yearly the next 2-5 years, focusing on gear when prices are high and miners when krypto prices are depressed. As my power-budget is fast consumed, I am looking into ETH-based miners which are very profitable right now - but certainly other asic offerings are better on power cost to revenue, any models to keep an extra close eye on?

Noone?

Don't know if it is Nicehash or some other big fish that shows up to the low network difficulty party - but sometimes the difficulty goes from 6 Mh to ~20 Mh near instantaneous. As long as the exchange price is low, the network hashrate keep going down - until profitabillity reaches a certain point. Then boom.

Someone must've done any work like what is outlined in the OP?

Hi,

I've got several years experience as a embedded programmer. Yet I find myself coming short when it comes to web scraping, scripts and fooling windows into doing what I want.

Basically I'm mining 3 Cryptonight / Cryptonode coins. The difficulty is varying a lot.

Coin X: Stable with high hashrate, ~250 Mh, pretty much regardless of price. ~70% of the time, I believe this is the most profitable coin (with regards to the future).

Coin Y: Price all over the place. Network hashrate going from 5 Mh to 40 Mh in a blink. Quite often, with future price estimate, this coin could be vastly more profitable than Coin X.

Coin Z: Stable price. Network hashrate going from ~10 Mh to ~40 Mh. To diversify my portofolio I'd like some of this aswell.

I want to achieve this:
1. Scrape the current difficulty on the coins from the web.
2. Multiply this with my own estimate of future price.
3. Mine that coin.
4. Reevaluate continously and swap to the coin that scores the highest (Preferably without re-compiling and restarting miner).
5. ....
6. Profit.

I think, done correctly, swapping between coins like this could increase yield from mining by 20-50% and also even the returns.

Can this be achieved? Cue discussion! Thanks for the attention so far 

Have a few rigs. Mining halts frequently on 2 different pools and switches over to other CN coins. Seems it is stable for 1-2h, then drops out.

Pool problem?
Anyone mining this share the same experience?