Bitcoin Forum

Hi!

Maybe I'm doing the math wrong here:

Current difficulty = 567358
Good rig efficiency = 2e6 hashes/Joule

Average energy per block = (567358*2³²/2e6) J = 1.22e9 J = 338 kWh

Price of electricity per block = 338 kWh * 0.1 USD/kWh = 33.8 USD

Divide by 50 BTC per block and we get 33.8 USD / 50BTC = 0.676 USD/BTC

It seems to me that if you already own some hardware capable of hashing, mining pays off twentyfold or more.  So I'm guessing my math is wrong?

yea you doing it wrong take you Mhs and then find out how much power you rig is pulling then see how many coins you get a day vs how much you power is a day

I'm working with the assumption that the posted Mhash/J numbers are correct, so I don't need to measure them again like you suggest.

It costs me around US$3 in power per BTC as one of my computers is less efficient.  I could cut that back to US$2.10 per BTC, but also slow down my hashing rate.  10c/kwh is very cheap power.  I have to pay the equivalent of 27c/kwh in Australia.

Ouch, that must kill. Isn't half your country a desert wasteland you could fill with solar panels? :P

I'd say 10c/kWh is a fair average for America though, seeing as some states have as high as .15, while states with strong hydro or nuclear programs have as low as .045 .

Could be part of the problem be that you are a basement mom and popi illegal operation? ;)

I plan putting up some gear and found out that if I put up a LOT  my price of electricity goes from 27 eurocents to 6 eurocents - industrial power is a lot cheaper once you take a lot more than a couple of households, and steadily.

naturally "I have some mining rig in my basement" won't cut it. 30 high power rigs in 3 racks do.

Or: I plan to rount out mining rig. Finance the rig. FInance the room. Finance the seucrity and administration. Cheaper than you pay for the electricity ;)

I'm getting a 1.5kw solar system in a few weeks, but even that will generate maybe 3kwh per day in the middle of winter.

Vast arrays of solar power would make sense in Australia, but it's still much cheaper to dig up coal and burn it.  Nuclear power is out of the equation and will never happen, despite Australia being one of the world's top uranium exporters.

Power here is expensive and growing at more than 10%/year, and that's before a carbon emissions tax (if that ever happens).  Australia is an expensive place to live.  Our housing costs triple that of the US market (post bubble) and I buy pretty much everything I can online from the USA and England to avoid the local retailer and distributor price gouging.  Books are half price off Amazon.com, inc air mail, etc.

If its any consolation, the australian housing bubble will pop at some point, so you will be able to buy a house cheaper.

Yeah, it's more like 1.5$-2$ per BTC:
- not everyone is efficient as that
- the PC has other components that use power to support mining
- even efficient miners need cooling costs (fans, AC, extra energy)
- you need to pay for the decaying hardware (buy price minus sell price)
- account for failures in hardware (shit breaks, 100% loss on PC parts)
- account for failures in software (badly configured software, human mistakes, automated mistakes, pools go down, internet goes down)
- internet subscriptions or traffic (where applies)
- rent or loss of usable space costs (where applies)
- security costs (guardsmen, watchmen, alarms, systems)

Now, besides this, let me ask you the following:
- how much BTC do we create each day?
- how much BTC do we sell each day?

Find the answers and you will understand.

That's pretty silly. Why can't Australian companies resell things at less than 100% markup?

In The Netherlands (ever looked it up at the map? :P) one kWh is about 0.32 USD...
But it's still profitable...

It's not a hard formula

(power consumption in kWh)(price per kWh)(Time to earn 1 btc in Hours) = Cost per BTC

According to Bitcoin Mining Calculator, 565 Mhash will give you 1 btc per day, so we'll use that as an example here

(power consumption in kWh)(price per kWh)(24) = Cost per BTC

Now, we'll be liberal with the power consumption here (2 5850s could get that rate OC'd, maybe even 2 5830s)

(.75 )(price per kWh)(24) = Cost per BTC

According to eia.gov, the average cost of power in America was $.0966

(.75 )(.0966)(24) = Cost per BTC

(.75 )(.0966)(24) = $1.7388

Have I disagreed with you on the power costs? Why do you show the calculation of power costs, when I included many other costs reported by forum users.

Please remember the average power in the US per kw does NOT include additional fees and taxes.  The state I live in has average costs, around the quoted 10c kw/hr.  But by the time I get my bill a good 35% of additional fees are tacked on making my real costs closer to 14c kw/hr than 10.  And that is not even including all the above real, non-trivial additional costs.

To the above laundry list of costs I'd like to add the labor cost to set up and maintain the mining gear.  But while that reflects true cost of BTC the original title is all about the power cost.  I'd say .7 is way too low, I'm planning using $2.5/btc and expecting to up that to $3 come next Tuesday, possibly $5 for the next difficulty jump.  I don't think we'll see $9/BTC in power costs for a very, very long time.

Sure, you dont need an equal amount of airconditiong to keep the mining rig cool since the
summer daytime high is only 22C. 

They very often won't be. They usually just use the TDP, and that will be wrong because they overclock and don't add overhead from other parts in the system and power conversion in the PSU.

Two difficulty rises later, we're up to, using a 800 watt (remember PSUs are not 100% efficient) overclocked quad 5830 setup:

280 Mhash * 4 = 1120 Mhash = .817 BTC/day (in actuality lower, since solo mining is impractical and pools are not 100% efficient)

800 watts * 24 hours = 19.2Kw/day

19.2Kw/day * $.14 Kw/hr = $2.688/day.

So what we have is $2.688 / .817 = $3.29 per bit coin without factoring in cooling, cost of hardware, etc etc.  Another way to look at it,

$17.50 - $3.29 * .817 = $11.6 daily return on a ~$900 investment.  Yuck!

Yeah, because you know, you can get 100% ROI in 2-3 months with just 20% risk in any other market, right?!

28C tomorrow... Summer has just begun...
But I don't have airconditioning, that's true :P Just open a window when things get to hot...

Yea its a good thing its mid-winter where I am. I find that I dont need a heater on when I would normally have one in use - I just use the heat from my PC to keep my room warm :)

Also realize that power costs vary significantly based on when you use your power.  Home users typically pay lower rates in regulated markets because they're assumed to use their power off-peak, while businesses pay high rates due to the expectation of peak hour usage.

Interestingly, for the "can't your just fill those deserts with solar panels" post, solar generation still doesn't really pay without significant subsidization from the government.  The payout on a panel using reasonable discount rate ALMOST works if you lie to yourself about it with the subsidies currently being offered in the US.

You know what else doesn't work without massive subsidies?  Digging up and burning coal. Yet that's where about half the power in the US comes from.  If all subsidies were eliminated, there would be many viable options that don't involve fossil fuels.  Look up Coal River Mountain in West Virginia. In order to avoid mountaintop removal mining, some people put together a proposal for a wind farm on the mountain.  It has some of the strongest, most consistent winds in this country.  The government would have received 1.7 million a year for the use of the land, and it would produce more energy at a lower cost than mining and burning the coal.  The coal company won out even though they only have to pay 36k a year to destroy the mountain.  All our state politicians are corrupt.  Wind was better all around, but the coal industry controls nearly all campaign funding.

Really not the point of my post.  I'm not a strong proponent of utilizing fossil fuels, either, but they're largely a better solution than photovoltaic cells right now.  Putting some subsidies out there to drive technology is a good thing, because it keeps people investing in R&D, so I'm not against the subsidies, but suggesting that building enough PV generation to supply power for large populations with the current state of the technology is off-base.

I can agree with that.  There are currently much better ways to do solar than PV panels.  Maybe one day, but we don't have it figured out yet.  A shitload of mirrors and a tower painted black with molten salt to transport the heat is much more efficient, and actually economical even in the fucked up political environment here in the states (in areas with enough sun).  I have no idea about Australia though.

The key thing is that you can't change things overnight.  Significant capital has been spent on our existing infrastructure and it's already bursting at the seams, so none of it is going offline anytime soon.  Things that provide obvious ROI will be done, things that are marginal will be done with some amount of subsidy, but mostly things that are safe will be done, which is why natural gas generation is almost the only thing that's been built significantly for some time.  Wind is the next most logical thing (with subsidies).  Other novel approaches will take someone leading the way and betting a lot of capital before they're widely adopted.

I assume you mean economically safe since there are many people near me with unsafe levels of methane in their water near where I live due to natural gas fracking.  A very large portion of people around here have no water lines and must rely on well water.  And if you were referring to CST as exotic, there are several plants in operation already and more are being built.

Yes, I mean economically safe.  Any yes, that's the process, a few people go out on a limb and build pilot plants (almost always with some sort of subsidy) and once things work out, more and larger plants are constructed utilizing the same technology.  The thing is, people won't pour in the billions of dollars required without either a government safety net or a very strong financial model.

I'm not saying you don't understand this, just clarifying my statement.

Yeah.... I'm just argumentative today ;).  Thanks for being my target.  You seem refeeshingly intelligent for these forums.  Hopefully those with interests in keeping things the way they are don't slow things down too much.  But I won't hold my breath.

LOL, no problem at all.  I'm pretty argumentative, too.  I'm sure we could go for rounds on the details... ;)