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Author Topic: Miners that pay for electricity should seriously start reconsidering  (Read 8090 times)
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August 09, 2011, 03:03:10 PM
Last edit: September 11, 2011, 09:41:23 PM by navigator
 #61

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Bert
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August 09, 2011, 06:18:51 PM
Last edit: August 10, 2011, 12:18:01 AM by Bert
 #62

For me  equilibrium is about a month away. Do I plan to sell my cards, with that much raw computing power I can think of a few other projects to use them for in small bursts, not 24/7 like they have been. Maybe even play a few games, without worrying about the drop in hash rate.

Here is the guts of a post I was going to make when I noticed this thread and instead of posting a new thread with a very confusing title of "Sky rocket or go Magma diving ?" I decided to add to this thread ..... they are both ultimately about your own personal equilibrium day.




Sorry for the poor beginning, I always seem to start my posts at the middle and work my way towards the beginning and finally get to the end.

Cost of Electricity per Kilowatt hour unit for me $0.25 (fixed)
Power used by my rig per day (about 220W x 3 + misc) circa 750Watts (24*0.750*0.25) = $4.50 (fixed, unless I add more hardware)
Hashed by rig per day on average 1300MH/sec @ current difficulty of 1888786.70535 is 0.692 BTC.

Assuming that 1 BTC is currently worth about $10 this would be $6.92 mined per day. Great news for me, I am printing money, at a profit using the current exchange rate.


If I assume that the value will increase in the future, I could print at a loss today for a possible profit tomorrow.
Or I could assume that BTC is a bad techo/nerd/geek/investment fad and the value will suddenly drop through the floor, and that I am printing money for a loss today and will be hit by an even larger loss tomorrow.

But I am an optimist and am reminded of that old saying "Always buy land, there ain't any more of it coming along any day soon", that is of course unless you live in Hawaii Smiley
But if you bought land 100 years ago, there is one thing for sure and that is that it will have appreciated in value. And if I bought land today, in 100 years time it will also have appreciate in value. In between there are ups and downs but overall the value it is up. I think of BTC in the same way as minerals, there is a limited fixed supply. There are ways to get more minerals, by bring them back to earth from space, but the extra mass would slowly spiral our planet into the Sun.


So anyhow back to the task at hand lets work backwards. i.e. At what difficulty will the cost of electricity for me  match the BTC being printed per day (at given exchange rates) ?



I have one constant the cost of electricity and two variables: the BTC generated per day on average and the exchange rate of BTC to dollars.
So to balance both sides of an equation I need to reduce the BTC generated per day to match my electricity costs.

$4.50/$10.00 would be 0.45 BTC per day to be operating at no loss and no profit. Or one 50BTC block found on average once every (50BTC/0.45BTC) 111.111111 days (111 days, 2 hours and 40 minutes)

Now here comes the flaw in trying to work out the magic difficulty, this duration of 111.111 days is larger than 14 days, which is the target duration of each new difficulty level (probably closer to 12 or 13 days in reality).
There is also a flaw that the future exchange rate all the way during the total 111.111 days will be constant and at today's assumed exchange rate of $10.00

Even with these two major flaws in the calculation both of which are unpredictable (BTC exchange rate and future difficulty growth[reduction] rate). Is having a flawed number better than having no number ? I would like to see a bad approximation rather than nothing.

The maths is trivial - see https://en.bitcoin.it/wiki/Difficulty#How_soon_might_I_expect_to_generate_a_block.3F I'm just flipping the formula to get a difficulty instead of an average time for a new block.

difficulty =  ( average duration for a block in seconds x hashrate in hashes per second) / 2^32  = ( 9,600,000 x 1,300,000,000 ) / 4,294,967,296 = 2,905,726.433

In my case a difficulty of 2905726.433 at a hash rate of 1.3Ghash/sec would yield one 50BTC block (ignoring block fees) found on average every 111 days, 2 hours and 40 minutes or 0.45BTC per day over 111.111 days (or a 54% increase from the current difficulty). This is as I mentioned assuming a constant exchange rate of $10 and a constant difficulty for 111.111 days of the 2905726.433 difficulty. 111.111 days divided by 14 days is 7.9, so the difficulty should have changed at least eight times during this period. But there is no way to know if the future difficulty will increase or decrease in the short term. In the long term it should increase, with increasingly more efferent future hardware.


Anyhow there is a decision that I will need to make, circa a month from now. Nothing is set in stone, the BTC exchange rate could sky rocket, or go magma diving. And the difficulty rate could increase (or decrease) more rapidly than expected. There should be enough information above to help you workout your own approximation to your own personal equilibrium day.

EDIT: Actually in about a months time it will be getting close to winter where I live, so maybe I will continue to mine for subsided heating. *evil grin* Maybe next spring/summer you will see a drop off in mining, but I think that every winter there will be an increase. Why generate heat without doing something useful to make the heat.

There is an interesting idea, electric BTC radiators. Increase the hash rate to increase the temperature, and throttle the sharerate to lower the temperature. Maybe pulse it 5 minutes generating then allow it 5 minutes of idle, and adjust the on/off ratio to adjust the average room temperature. It would definitely be an idea that would get media attention. Although I don't know if it would be in a good way, or a bad way.

Anyhow here is a simple table, everyone loves tables, well except those who love graphs, bloody hedonists.
Code:
$/BTC                                          cost of used electricity per hour (US cents)
            5        6        7        8        9       10       11       12       15       20     22.5       25       30       40
    1 The past The past The past The past The past The past The past The past The past The past The past The past The past The past
    5  5448237  4540197  3891597  3405148  3026798  2724118  2476471  2270098 The past The past The past The past The past The past
  7.5  8172355  6810296  5837396  5107722  4540197  4086177  3714707  3405148  2724118  2043088 The past The past The past The past
   10 10896474  9080395  7783195  6810296  6053596  5448237  4952942  4540197  3632158  2724118  2421438  2179294 The past The past
 12.5 13620592 11350493  9728994  8512870  7566995  6810296  6191178  5675246  4540197  3405148  3026798  2724118  2270098 The past
   15 16344711 13620592 11674793 10215444  9080395  8172355  7429414  6810296  5448237  4086177  3632158  3268942  2724118  2043088
 17.5 19068829 15890691 13620592 11918018 10593794  9534414  8667649  7945345  6356276  4767207  4237517  3813765  3178138  2383603
   20 21792948 18160790 15566391 13620592 12107193 10896474  9905885  9080395  7264316  5448237  4842877  4358589  3632158  2724118
   25 27241185 22700987 19457989 17025740 15133991 13620592 12382356 11350493  9080395  6810296  6053596  5448237  4540197  3405148
   30 32689422 27241185 23349587 20430888 18160790 16344711 14858828 13620592 10896474  8172355  7264316  6537884  5448237  4086177
   35 38137659 31781382 27241185 23836037 21187588 19068829 17335299 15890691 12712553  9534414  8475035  7627531  6356276  4767207
   40 43585896 36321580 31132783 27241185 24214386 21792948 19811771 18160790 14528632 10896474  9685754  8717179  7264316  5448237
   45 49034133 40861777 35024381 30646333 27241185 24517066 22288242 20430888 16344711 12258533 10896474  9806826  8172355  6129266
   50 54482370 45401975 38915979 34051481 30267983 27241185 24764713 22700987 18160790 13620592 12107193 10896474  9080395  6810296
   75 81723555 68102963 58373968 51077222 45401975 40861777 37147070 34051481 27241185 20430888 18160790 16344711 13620592 10215444
The top row is cost in US cents per KWhour of electricity and the first column is the BTC to US dollar exchange rate.

You are either ON the table or OFF the table. This is because "average duration for a block in seconds x hashrate in hashes per second" is a constant for everyone mining. So if you are mining less than the required number of BTC's a day to break even you can not be on the table above. So in my case I am mining 0.69 BTC per day (1.3Ghash/sec) and my electricity cost is 0.45 BTC per day. If I was CPU mining at 10MHash/second generating 0.01 BTC a day with the same power cost of  0.45 BTC per day (or anything greater than 0.01), even though I could read values from the above table, I would be asleep probably in deep space and would definitely not be ON the above table. My current exchange rate ($10 per BTC) and current cost (18.75 cents per hour) of electricity would be there and point to a cell with the difficulty equilibrium answer if I was mining sensibly.

So My rig uses 750 watts per hour or 0.75 KW hours at 25 cents per KW hour unit. Thats 18.75 cents (0.75*25) , the 20 cent column is the closest to my true value and at a current exchange rate of $10 would give the approximate value of 2724118 for 20 cents but if I adjust this (20/18.75*2724118 = 2,905,725.867) I get the same value as above, or as close as makes no difference: 2,905,725.867 instead of 2,905,726.433


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September 06, 2011, 06:24:27 PM
 #63

There's absolutely no reason to mine at a loss beyond equilibrium, when you can just buy the same amount of BTC for LESS money!!!

For me  equilibrium is about a month away. Do I plan to sell my cards, with that much raw computing power I can think of a few other projects to use them for in small bursts, not 24/7 like they have been. Maybe even play a few games, without worrying about the drop in hash rate.

Here is the guts of a post I was going to make when I noticed this thread and instead of posting a new thread with a very confusing title of "Sky rocket or go Magma diving ?" I decided to add to this thread ..... they are both ultimately about your own personal equilibrium day.




Sorry for the poor beginning, I always seem to start my posts at the middle and work my way towards the beginning and finally get to the end.

Cost of Electricity per Kilowatt hour unit for me $0.25 (fixed)
Power used by my rig per day (about 220W x 3 + misc) circa 750Watts (24*0.750*0.25) = $4.50 (fixed, unless I add more hardware)
Hashed by rig per day on average 1300MH/sec @ current difficulty of 1888786.70535 is 0.692 BTC.

Assuming that 1 BTC is currently worth about $10 this would be $6.92 mined per day. Great news for me, I am printing money, at a profit using the current exchange rate.


If I assume that the value will increase in the future, I could print at a loss today for a possible profit tomorrow.
Or I could assume that BTC is a bad techo/nerd/geek/investment fad and the value will suddenly drop through the floor, and that I am printing money for a loss today and will be hit by an even larger loss tomorrow.

But I am an optimist and am reminded of that old saying "Always buy land, there ain't any more of it coming along any day soon", that is of course unless you live in Hawaii Smiley
But if you bought land 100 years ago, there is one thing for sure and that is that it will have appreciated in value. And if I bought land today, in 100 years time it will also have appreciate in value. In between there are ups and downs but overall the value it is up. I think of BTC in the same way as minerals, there is a limited fixed supply. There are ways to get more minerals, by bring them back to earth from space, but the extra mass would slowly spiral our planet into the Sun.


So anyhow back to the task at hand lets work backwards. i.e. At what difficulty will the cost of electricity for me  match the BTC being printed per day (at given exchange rates) ?



I have one constant the cost of electricity and two variables: the BTC generated per day on average and the exchange rate of BTC to dollars.
So to balance both sides of an equation I need to reduce the BTC generated per day to match my electricity costs.

$4.50/$10.00 would be 0.45 BTC per day to be operating at no loss and no profit. Or one 50BTC block found on average once every (50BTC/0.45BTC) 111.111111 days (111 days, 2 hours and 40 minutes)

Now here comes the flaw in trying to work out the magic difficulty, this duration of 111.111 days is larger than 14 days, which is the target duration of each new difficulty level (probably closer to 12 or 13 days in reality).
There is also a flaw that the future exchange rate all the way during the total 111.111 days will be constant and at today's assumed exchange rate of $10.00

Even with these two major flaws in the calculation both of which are unpredictable (BTC exchange rate and future difficulty growth[reduction] rate). Is having a flawed number better than having no number ? I would like to see a bad approximation rather than nothing.

The maths is trivial - see https://en.bitcoin.it/wiki/Difficulty#How_soon_might_I_expect_to_generate_a_block.3F I'm just flipping the formula to get a difficulty instead of an average time for a new block.

difficulty =  ( average duration for a block in seconds x hashrate in hashes per second) / 2^32  = ( 9,600,000 x 1,300,000,000 ) / 4,294,967,296 = 2,905,726.433

In my case a difficulty of 2905726.433 at a hash rate of 1.3Ghash/sec would yield one 50BTC block (ignoring block fees) found on average every 111 days, 2 hours and 40 minutes or 0.45BTC per day over 111.111 days (or a 54% increase from the current difficulty). This is as I mentioned assuming a constant exchange rate of $10 and a constant difficulty for 111.111 days of the 2905726.433 difficulty. 111.111 days divided by 14 days is 7.9, so the difficulty should have changed at least eight times during this period. But there is no way to know if the future difficulty will increase or decrease in the short term. In the long term it should increase, with increasingly more efferent future hardware.


Anyhow there is a decision that I will need to make, circa a month from now. Nothing is set in stone, the BTC exchange rate could sky rocket, or go magma diving. And the difficulty rate could increase (or decrease) more rapidly than expected. There should be enough information above to help you workout your own approximation to your own personal equilibrium day.

EDIT: Actually in about a months time it will be getting close to winter where I live, so maybe I will continue to mine for subsided heating. *evil grin* Maybe next spring/summer you will see a drop off in mining, but I think that every winter there will be an increase. Why generate heat without doing something useful to make the heat.

There is an interesting idea, electric BTC radiators. Increase the hash rate to increase the temperature, and throttle the sharerate to lower the temperature. Maybe pulse it 5 minutes generating then allow it 5 minutes of idle, and adjust the on/off ratio to adjust the average room temperature. It would definitely be an idea that would get media attention. Although I don't know if it would be in a good way, or a bad way.

Anyhow here is a simple table, everyone loves tables, well except those who love graphs, bloody hedonists.
Code:
$/BTC                                          cost of used electricity per hour (US cents)
            5        6        7        8        9       10       11       12       15       20     22.5       25       30       40
    1 The past The past The past The past The past The past The past The past The past The past The past The past The past The past
    5  5448237  4540197  3891597  3405148  3026798  2724118  2476471  2270098 The past The past The past The past The past The past
  7.5  8172355  6810296  5837396  5107722  4540197  4086177  3714707  3405148  2724118  2043088 The past The past The past The past
   10 10896474  9080395  7783195  6810296  6053596  5448237  4952942  4540197  3632158  2724118  2421438  2179294 The past The past
 12.5 13620592 11350493  9728994  8512870  7566995  6810296  6191178  5675246  4540197  3405148  3026798  2724118  2270098 The past
   15 16344711 13620592 11674793 10215444  9080395  8172355  7429414  6810296  5448237  4086177  3632158  3268942  2724118  2043088
 17.5 19068829 15890691 13620592 11918018 10593794  9534414  8667649  7945345  6356276  4767207  4237517  3813765  3178138  2383603
   20 21792948 18160790 15566391 13620592 12107193 10896474  9905885  9080395  7264316  5448237  4842877  4358589  3632158  2724118
   25 27241185 22700987 19457989 17025740 15133991 13620592 12382356 11350493  9080395  6810296  6053596  5448237  4540197  3405148
   30 32689422 27241185 23349587 20430888 18160790 16344711 14858828 13620592 10896474  8172355  7264316  6537884  5448237  4086177
   35 38137659 31781382 27241185 23836037 21187588 19068829 17335299 15890691 12712553  9534414  8475035  7627531  6356276  4767207
   40 43585896 36321580 31132783 27241185 24214386 21792948 19811771 18160790 14528632 10896474  9685754  8717179  7264316  5448237
   45 49034133 40861777 35024381 30646333 27241185 24517066 22288242 20430888 16344711 12258533 10896474  9806826  8172355  6129266
   50 54482370 45401975 38915979 34051481 30267983 27241185 24764713 22700987 18160790 13620592 12107193 10896474  9080395  6810296
   75 81723555 68102963 58373968 51077222 45401975 40861777 37147070 34051481 27241185 20430888 18160790 16344711 13620592 10215444
The top row is cost in US cents per KWhour of electricity and the first column is the BTC to US dollar exchange rate.

You are either ON the table or OFF the table. This is because "average duration for a block in seconds x hashrate in hashes per second" is a constant for everyone mining. So if you are mining less than the required number of BTC's a day to break even you can not be on the table above. So in my case I am mining 0.69 BTC per day (1.3Ghash/sec) and my electricity cost is 0.45 BTC per day. If I was CPU mining at 10MHash/second generating 0.01 BTC a day with the same power cost of  0.45 BTC per day (or anything greater than 0.01), even though I could read values from the above table, I would be asleep probably in deep space and would definitely not be ON the above table. My current exchange rate ($10 per BTC) and current cost (18.75 cents per hour) of electricity would be there and point to a cell with the difficulty equilibrium answer if I was mining sensibly.

So My rig uses 750 watts per hour or 0.75 KW hours at 25 cents per KW hour unit. Thats 18.75 cents (0.75*25) , the 20 cent column is the closest to my true value and at a current exchange rate of $10 would give the approximate value of 2724118 for 20 cents but if I adjust this (20/18.75*2724118 = 2,905,725.867) I get the same value as above, or as close as makes no difference: 2,905,725.867 instead of 2,905,726.433



btc: 15sFnThw58hiGHYXyUAasgfauifTEB1ZF6
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September 08, 2011, 02:42:18 PM
 #64

There's absolutely no reason to mine at a loss beyond equilibrium, when you can just buy the same amount of BTC for LESS money!!!


That is true, apart from it is not at loss it is heating the house during winter. So in effect it is subsidised heating. But come next spring it will be time, for me anyhow, to stop mining and buy Bitcoins.

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September 08, 2011, 06:46:23 PM
 #65

I rented a new place.
I pay only 10$ [in local currency] for electricity no matter how much kw's i use  Grin

I am thinking of creating a bitcoin farm  Roll Eyes
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September 08, 2011, 07:29:26 PM
 #66

I rented a new place.
I pay only 10$ [in local currency] for electricity no matter how much kw's i use  Grin

I am thinking of creating a bitcoin farm  Roll Eyes

Start your farm, and see how long that lasts.

Just because they don't care if you run your stove 10 minutes or 20 minutes doesn't mean they don't care if you run a small server farm in the house.

You see, if you exclude things like server farms, electricity use CAN be guessed or estimated. Most people take a shower, make some breakfast, wash 1 weeks' worth of clothes each week, watch a few hours' TV, leave a PC on 24/7, etc.

But if you start a science lab in your basement, and run up a $500/month electric bill trying to re-create Frankenstein's monster, you can bet the landlord WILL notice.

I'm sure that the landlord's first $400 electric bill for your house will cause him to pay you a visit. He's not in the business of losing money.
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September 08, 2011, 08:42:14 PM
 #67

I rented a new place.
I pay only 10$ [in local currency] for electricity no matter how much kw's i use  Grin

I am thinking of creating a bitcoin farm  Roll Eyes

Start your farm, and see how long that lasts.

Just because they don't care if you run your stove 10 minutes or 20 minutes doesn't mean they don't care if you run a small server farm in the house.

You see, if you exclude things like server farms, electricity use CAN be guessed or estimated. Most people take a shower, make some breakfast, wash 1 weeks' worth of clothes each week, watch a few hours' TV, leave a PC on 24/7, etc.

But if you start a science lab in your basement, and run up a $500/month electric bill trying to re-create Frankenstein's monster, you can bet the landlord WILL notice.

I'm sure that the landlord's first $400 electric bill for your house will cause him to pay you a visit. He's not in the business of losing money.

So..  he will get free electricity for at least a month and possibly more until your landlord goes through proper evition procedure.
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September 08, 2011, 08:42:37 PM
 #68

I rented a new place.
I pay only 10$ [in local currency] for electricity no matter how much kw's i use  Grin

I am thinking of creating a bitcoin farm  Roll Eyes

Start your farm, and see how long that lasts.

Just because they don't care if you run your stove 10 minutes or 20 minutes doesn't mean they don't care if you run a small server farm in the house.

You see, if you exclude things like server farms, electricity use CAN be guessed or estimated. Most people take a shower, make some breakfast, wash 1 weeks' worth of clothes each week, watch a few hours' TV, leave a PC on 24/7, etc.

But if you start a science lab in your basement, and run up a $500/month electric bill trying to re-create Frankenstein's monster, you can bet the landlord WILL notice.

I'm sure that the landlord's first $400 electric bill for your house will cause him to pay you a visit. He's not in the business of losing money.

So..  he will get free electricity for at least a month and possibly more until your landlord goes through proper eviction procedure?
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September 09, 2011, 05:10:31 AM
 #69

I rented a new place.
I pay only 10$ [in local currency] for electricity no matter how much kw's i use  Grin

I am thinking of creating a bitcoin farm  Roll Eyes

Start your farm, and see how long that lasts.

Just because they don't care if you run your stove 10 minutes or 20 minutes doesn't mean they don't care if you run a small server farm in the house.

You see, if you exclude things like server farms, electricity use CAN be guessed or estimated. Most people take a shower, make some breakfast, wash 1 weeks' worth of clothes each week, watch a few hours' TV, leave a PC on 24/7, etc.

But if you start a science lab in your basement, and run up a $500/month electric bill trying to re-create Frankenstein's monster, you can bet the landlord WILL notice.

I'm sure that the landlord's first $400 electric bill for your house will cause him to pay you a visit. He's not in the business of losing money.
No sir, here is the thing.
There is no KW-Meters thingy.
The 10$ [50 Egyptian pounds] is a fine for not installing one <= which is totally legal.
And i am fine with that fine Cheesy
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September 09, 2011, 05:11:34 AM
 #70

If you get "free" electricity. Isnt that in your contract/lease?
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September 09, 2011, 05:53:29 AM
 #71

So..  he will get free electricity for at least a month and possibly more until your landlord goes through proper eviction procedure?
No, he have no way of finding how much KW i used.
So i get free electricity and pay a 10$ each month as a fine.

And no that won't change in the -near- future.
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September 09, 2011, 04:03:15 PM
 #72

Yep, eventually the mining game will be limited to people with free or low flat electricity cost, like newminerr. Basically anyone paying more than 0.5c per KW is going to be looking at mining at a loss in the near future, you just can't compete with people like newminerr that pay $10 flat for unlimited electricity.

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September 09, 2011, 04:21:38 PM
 #73

Yep, eventually the mining game will be limited to people with free or low flat electricity cost, like newminerr. Basically anyone paying more than 0.5c per KW is going to be looking at mining at a loss in the near future, you just can't compete with people like newminerr that pay $10 flat for unlimited electricity.
If the price stays this low difficulty will drastically lower making it profitable again for quite a few people who do pay electricity.
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September 11, 2011, 10:49:08 AM
 #74

Yep, eventually the mining game will be limited to people with free or low flat electricity cost, like newminerr. Basically anyone paying more than 0.5c per KW is going to be looking at mining at a loss in the near future, you just can't compete with people like newminerr that pay $10 flat for unlimited electricity.
If the price stays this low difficulty will drastically lower making it profitable again for quite a few people who do pay electricity.

I hope so.
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