Mining farms in the US how is demand calculated with electrical rate?

[Bjorn_Blockchain]

I'm trying to calculate what our bill would be assuming these factors:

Power draw would be 75,000 watts constant.
Rate is $ 0.04644 per kwh
Demand Charge, per kw $ 3.40

Demand charge kicks in after exceeding 7,500 KW month.

I calculated our farm would be using roughly 54,000 KW a month.

Can anyone who has intimate experience in calculating Kwh and demand able to figure out the monthly bill including demand charge on the figures I've posted please. Help would be really appreciated.

[bsobel]

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

[Entropy-uc]

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

This is largely correct.  In practice your demand needs to be scaled up to account for losses after the meter in conductors and transformers.  This will add 5-10%.  Plus your actual usage will increase with temperature so expect an additional 5-10% for your peak loading versus the average.

You also will need to budget for your cooling load.  75 kW of miners cannot be passively cooled, so you will have to account for the fans and A/C required to keep the space in temperature control.

Free advice.  Take 1/2 of what you think you will invest and just put it in bitcoins.  Use the other half for your buildout. When you have things under control at half capacity and understand the profitability and risks you can make a decision about building out to full capacity.

[Bjorn_Blockchain]

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

This is largely correct.  In practice your demand needs to be scaled up to account for losses after the meter in conductors and transformers.  This will add 5-10%.  Plus your actual usage will increase with temperature so expect an additional 5-10% for your peak loading versus the average.

You also will need to budget for your cooling load.  75 kW of miners cannot be passively cooled, so you will have to account for the fans and A/C required to keep the space in temperature control.

Free advice.  Take 1/2 of what you think you will invest and just put it in bitcoins.  Use the other half for your buildout. When you have things under control at half capacity and understand the profitability and risks you can make a decision about building out to full capacity.

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

Thank you both for the advice, very appreciated. Our team is at 36 KW now so we understand the cooling aspect, however I wanted to ensure the demand charge was a one time per month peak only charge and this info wasn't readily available in plain English on the utility website.

[unholycactus]

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

This is largely correct.  In practice your demand needs to be scaled up to account for losses after the meter in conductors and transformers.  This will add 5-10%.  Plus your actual usage will increase with temperature so expect an additional 5-10% for your peak loading versus the average.

You also will need to budget for your cooling load.  75 kW of miners cannot be passively cooled, so you will have to account for the fans and A/C required to keep the space in temperature control.

Free advice.  Take 1/2 of what you think you will invest and just put it in bitcoins.  Use the other half for your buildout. When you have things under control at half capacity and understand the profitability and risks you can make a decision about building out to full capacity.

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

Thank you both for the advice, very appreciated. Our team is at 36 KW now so we understand the cooling aspect, however I wanted to ensure the demand charge was a one time per month peak only charge and this info wasn't readily available in plain English on the utility website.

It should correspond to the peak yes.
There are probably costs associated with the infrastructure required to supply the power as well.

[paintballrefjosh]

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

This is largely correct.  In practice your demand needs to be scaled up to account for losses after the meter in conductors and transformers.  This will add 5-10%.  Plus your actual usage will increase with temperature so expect an additional 5-10% for your peak loading versus the average.

You also will need to budget for your cooling load.  75 kW of miners cannot be passively cooled, so you will have to account for the fans and A/C required to keep the space in temperature control.

Free advice.  Take 1/2 of what you think you will invest and just put it in bitcoins.  Use the other half for your buildout. When you have things under control at half capacity and understand the profitability and risks you can make a decision about building out to full capacity.

I partially agree with your cooling statement and partially disagree.  You don't need AC to cool them but you do need a lot of air movement to get the heat away.  I've got around 96 KW going right now in Texas with only large fans removing air from the room to outside my building and it works fine.

[Entropy-uc]

75*3.4  plus (75 * 0.4644 * 24 * 30)

Your demand charge is easy as you have constant demand.  Demmand charges are really for traditional businesses which need more whatts during certain hours.  Your 24/7 and can just multiply and get them.

This is largely correct.  In practice your demand needs to be scaled up to account for losses after the meter in conductors and transformers.  This will add 5-10%.  Plus your actual usage will increase with temperature so expect an additional 5-10% for your peak loading versus the average.

You also will need to budget for your cooling load.  75 kW of miners cannot be passively cooled, so you will have to account for the fans and A/C required to keep the space in temperature control.

Free advice.  Take 1/2 of what you think you will invest and just put it in bitcoins.  Use the other half for your buildout. When you have things under control at half capacity and understand the profitability and risks you can make a decision about building out to full capacity.

I partially agree with your cooling statement and partially disagree.  You don't need AC to cool them but you do need a lot of air movement to get the heat away.  I've got around 96 KW going right now in Texas with only large fans removing air from the room to outside my building and it works fine.

Do your fans run on good intentions? 

In the real world fans require power and that is part of the total demand that OP is asking about.

[paintballrefjosh]

I don't know what you read but your response makes little sense.  I didn't say fans use zero electricity.  I simply stated you don't need AC which is extremely expensive if you plan to cool a sealed room of these miners.  All you need, even in a hotter climate, is good airflow from a decent quality exhaust fan or similar.

[Raymond_B]

I don't know what you read but your response makes little sense.  I didn't say fans use zero electricity.  I simply stated you don't need AC which is extremely expensive if you plan to cool a sealed room of these miners.  All you need, even in a hotter climate, is good airflow from a decent quality exhaust fan or similar.

I am glad you posted, that is good information. I am in Texas as well and was planning to cool the cold side of a 40-60 miner setup (to start) in a 1,000 sq/ft warehouse. Do you have your miners set up that way or are they open with just good exhaust fans?

[paintballrefjosh]

Mine are open no cooling.  GPUs did fine last summer so we'll see how the ASICs perform.  Worst case I'll offset the heat slightly with some AC but I don't ever plan to cool the room down to 60 degrees, that's just a waste of money.

[Raymond_B]

Mine are open no cooling.  GPUs did fine last summer so we'll see how the ASICs perform.  Worst case I'll offset the heat slightly with some AC but I don't ever plan to cool the room down to 60 degrees, that's just a waste of money.

100% agree, I was simply talking about the cold isle of my setup, which would only be like 20-30 sq/ft. And I was thinking 70-75F would be fine, maybe even warmer.

[paintballrefjosh]

Got it.  It would obviously be nice to be in a colder climate but we'll survive with good quality fans

[Raymond_B]

Got it.  It would obviously be nice to be in a colder climate but we'll survive with good quality fans

Right on

[QuintLeo]

Mine are open no cooling.  GPUs did fine last summer so we'll see how the ASICs perform.  Worst case I'll offset the heat slightly with some AC but I don't ever plan to cool the room down to 60 degrees, that's just a waste of money.

100% agree, I was simply talking about the cold isle of my setup, which would only be like 20-30 sq/ft. And I was thinking 70-75F would be fine, maybe even warmer.

 80 F is plenty cool - even Yahoo doesn't build their new data centers to go below that.

 Look up "yahoo chicken coop" on Google sometime.

[bsobel]

I don't know what you read but your response makes little sense.  I didn't say fans use zero electricity.  I simply stated you don't need AC which is extremely expensive if you plan to cool a sealed room of these miners.  All you need, even in a hotter climate, is good airflow from a decent quality exhaust fan or similar.

I will just add, be sure you get exhaust fans which are rated for higher heat.  Most off the shelf (e.g. Grainger) fans are rated to 104.  In the Texas summers thats too close to ambient for my liking.  I use commercial grease fans (restaurants use them) which are rated to 300f.  I'd hate for a fan to fail because its summer and then lose the miners because the air cooling stopped.   I also put in 3 instead of the 2 I needed (because Im paranoid like that).  One set to turn on at 80, another 90, the third 100.  The third should never run, but if another fan fails during a heatwave it will.