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Bitcoin => Mining => Topic started by: cbeast on May 27, 2011, 09:02:39 PM



Title: Calculating heat generated.
Post by: cbeast on May 27, 2011, 09:02:39 PM
I see that there are spreadsheets for calculating the BTC/Electricity to determine profitability. I live in the Southern US where it gets very hot in the summertime. I will also need A/C to vent out the heat from the GPU/CPU cooling system. Any idea on how much heat is emitted in terms of BTUs?


Title: Re: Calculating heat generated.
Post by: bobR on May 27, 2011, 09:11:43 PM
I see that there are spreadsheets for calculating the BTC/Electricity to determine profitability. I live in the Southern US where it gets very hot in the summertime. I will also need A/C to vent out the heat from the GPU/CPU cooling system. Any idea on how much heat is emitted in terms of BTUs?

btu's are heat
every Watt used per hr is 3.414btu per hr
the heat has to go somewhere... you can't cool something with warmer air



Title: Re: Calculating heat generated.
Post by: cbeast on May 27, 2011, 10:02:30 PM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.


Title: Re: Calculating heat generated.
Post by: allinvain on May 27, 2011, 10:10:39 PM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.

Umm yes and no. What you're doing is using electricity to heat your home instead of natural gas. In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs. The thing is that you'd have to figure out some way to push all that heat from the miners and circulate it around the house. I wonder if anyone has setup a ghetto rig to push the heat into a furnace's ducts.


Title: Re: Calculating heat generated.
Post by: xenon481 on May 27, 2011, 10:19:21 PM
In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs.

In my part of the US, Heating/Cooking/WaterHeating with Natural Gas is significantly cheaper than doing the equivalent with electricity.


Title: Re: Calculating heat generated.
Post by: w128 on May 27, 2011, 10:44:44 PM
In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs.

Where in the world are you?

There is absolutely no comparison between gas and electric heat where I am. I paid about $60 a month to keep a 4000 sq. ft house toasty warm with gas last winter.

I'd be better off burning dollar bills to keep warm than paying for electric heat.


Title: Re: Calculating heat generated.
Post by: benjamindees on May 27, 2011, 10:48:28 PM
Electricity can be cheaper if you use a heat pump.

You can use Google to convert Watts to BTU/hr:
http://www.google.com/search?q=188+watt+in+BTU%2Fhr

One Ton of cooling is 12,000 BTU/hr:
http://en.wikipedia.org/wiki/Ton#Refrigeration

Remember electric heaters are nearly 100% efficient, while gas can range from 40-100%.


Title: Re: Calculating heat generated.
Post by: cbeast on May 28, 2011, 12:15:52 AM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.

Umm yes and no. What you're doing is using electricity to heat your home instead of natural gas. In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs. The thing is that you'd have to figure out some way to push all that heat from the miners and circulate it around the house. I wonder if anyone has setup a ghetto rig to push the heat into a furnace's ducts.

I have a fireplace with a heatilator (sp?) circulating system. I suppose I could place the mining rig there and use a video monitor to display a GPU generated fireplace display.  :D


Title: Re: Calculating heat generated.
Post by: SgtSpike on May 28, 2011, 12:23:18 AM
I don't understand the conversion of watts to BTUs with regards to A/C units...

I have a Window A/C unit rated at 10,000 BTUs, but it only draws 9 amps max, which is equivalent to 1,080w.  Yet on the wiki site, it says that 12,000 BTUs is 3,517w.

I would have expected A/C to be LESS efficient than heat at the same wattage, not more... so is it true that a 12,000 BTU A/C unit can remove 3,517w worth of heat?


Title: Re: Calculating heat generated.
Post by: allinvain on May 28, 2011, 02:18:03 AM
In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs.

Where in the world are you?

There is absolutely no comparison between gas and electric heat where I am. I paid about $60 a month to keep a 4000 sq. ft house toasty warm with gas last winter.

I'd be better off burning dollar bills to keep warm than paying for electric heat.

I'm in Canada. You know what let me check my gas bill cause I may have spoken with my ass lol :p..one moment plz..nope I was correct..I pay $0.14 per cubic meter of gas, but pay only $0.06 in the winter for electricity.



Title: Re: Calculating heat generated.
Post by: allinvain on May 28, 2011, 02:20:57 AM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.

Umm yes and no. What you're doing is using electricity to heat your home instead of natural gas. In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs. The thing is that you'd have to figure out some way to push all that heat from the miners and circulate it around the house. I wonder if anyone has setup a ghetto rig to push the heat into a furnace's ducts.

I have a fireplace with a heatilator (sp?) circulating system. I suppose I could place the mining rig there and use a video monitor to display a GPU generated fireplace display.  :D

Well, what you ideally want is to circulate the heat throughout the whole house not just in the room where the fireplace is. Otherwise your miners will be eating that hot air. Ideally what would be best like I said is to put the miners in the basement and feed the hot air the give out straight into the furnaces air circulation system (it's a giant fan lol).


Title: Re: Calculating heat generated.
Post by: inh on May 28, 2011, 02:31:05 AM
I don't understand the conversion of watts to BTUs with regards to A/C units...

I have a Window A/C unit rated at 10,000 BTUs, but it only draws 9 amps max, which is equivalent to 1,080w.  Yet on the wiki site, it says that 12,000 BTUs is 3,517w.

I would have expected A/C to be LESS efficient than heat at the same wattage, not more... so is it true that a 12,000 BTU A/C unit can remove 3,517w worth of heat?

Your A/C isn't a heater or a cooler, its  a heat pump. It moves heat from one place to another. Takes the heat in your room and pumps it outside It's not converting the electricity in to cold and pumping it in. The electricity is used up whiel the A/C does the work of moving the heat from inside to outside.


Title: Re: Calculating heat generated.
Post by: xenon481 on May 28, 2011, 02:35:33 AM
I don't understand the conversion of watts to BTUs with regards to A/C units...

I have a Window A/C unit rated at 10,000 BTUs, but it only draws 9 amps max, which is equivalent to 1,080w.  Yet on the wiki site, it says that 12,000 BTUs is 3,517w.

I would have expected A/C to be LESS efficient than heat at the same wattage, not more... so is it true that a 12,000 BTU A/C unit can remove 3,517w worth of heat?

Your A/C isn't a heater or a cooler, its  a heat pump. It moves heat from one place to another. Takes the heat in your room and pumps it outside It's not converting the electricity in to cold and pumping it in. The electricity is used up whiel the A/C does the work of moving the heat from inside to outside.

This is not true for standard Central Air Conditioning. (with the exception of heat pumps)


Title: Re: Calculating heat generated.
Post by: SgtSpike on May 28, 2011, 03:42:21 AM
I don't understand the conversion of watts to BTUs with regards to A/C units...

I have a Window A/C unit rated at 10,000 BTUs, but it only draws 9 amps max, which is equivalent to 1,080w.  Yet on the wiki site, it says that 12,000 BTUs is 3,517w.

I would have expected A/C to be LESS efficient than heat at the same wattage, not more... so is it true that a 12,000 BTU A/C unit can remove 3,517w worth of heat?

Your A/C isn't a heater or a cooler, its  a heat pump. It moves heat from one place to another. Takes the heat in your room and pumps it outside It's not converting the electricity in to cold and pumping it in. The electricity is used up whiel the A/C does the work of moving the heat from inside to outside.
Dang... well that's cool!  Thanks for the explanation.


Title: Re: Calculating heat generated.
Post by: benjamindees on May 28, 2011, 03:59:17 AM
Your A/C isn't a heater or a cooler, its  a heat pump. It moves heat from one place to another. Takes the heat in your room and pumps it outside It's not converting the electricity in to cold and pumping it in. The electricity is used up whiel the A/C does the work of moving the heat from inside to outside.

This is not true for standard Central Air Conditioning. (with the exception of heat pumps)

Wrong.  That description is perfectly accurate.



Title: Re: Calculating heat generated.
Post by: allinvain on May 28, 2011, 04:35:20 PM
http://home.howstuffworks.com/ac1.htm

http://en.wikipedia.org/wiki/Air_conditioner

debate over...



Title: Re: Calculating heat generated.
Post by: keybaud on May 28, 2011, 05:26:46 PM
http://home.howstuffworks.com/ac1.htm

http://en.wikipedia.org/wiki/Air_conditioner

debate over...



Or in simple terms, an AC also creates its own heat in order to move heat from somewhere else, so it needs to be able to cool its own output as well as the environment it is in.


Title: Re: Calculating heat generated.
Post by: compro01 on May 29, 2011, 06:59:15 AM
In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs.

Where in the world are you?

There is absolutely no comparison between gas and electric heat where I am. I paid about $60 a month to keep a 4000 sq. ft house toasty warm with gas last winter.

I'd be better off burning dollar bills to keep warm than paying for electric heat.

I'm in Canada. You know what let me check my gas bill cause I may have spoken with my ass lol :p..one moment plz..nope I was correct..I pay $0.14 per cubic meter of gas, but pay only $0.06 in the winter for electricity.



You need to check your units.  a cubic metre of gas is a lot more energy than a kilowatt-hour of electricity.

On equal units:

a gigajoule of natural gas (26.3 cubic metres) costs me $4.55 ($0.1725/cubic metre)

a gigajoule of electricity (278 kilowatt-hours) costs me $24.93 ($0.09/kilowatt-hour)

Even using your prices, natural gas is still way cheaper ($16.68 vs. $3.68).


Title: Re: Calculating heat generated.
Post by: mathx on May 29, 2011, 07:34:17 AM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.

Umm yes and no. What you're doing is using electricity to heat your home instead of natural gas. In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs. The thing is that you'd have to figure out some way to push all that heat from the miners and circulate it around the house. I wonder if anyone has setup a ghetto rig to push the heat into a furnace's ducts.

Electricity isnt anywhere close to cheaper than natgas, or people would be running generators all the time to make electricity to save money. This would quickly make the prices equal (modulo some consideration for ease of use/transport, etc).

The other way around. nat gas is about 3.5c/kWh of heat here for us. Electricity is about 12c/kWh.

If you are going to run your rig on electricity, then your electricity for the rig in winter, assuming it heats the house in the right places nicely (perhaps not, fan noise keeps it away from humans and humans are the thing that need heating, most of the rest of the house would be happy at 35F/2C all winter), then that just makes your electricity cheaper - 12-3.5 = 7.5c/kWh of power.

In summer its the opposite, with nearly double the cost for power + cooling. Not to mention extra AC noise and capital cost for the AC.


Title: Re: Calculating heat generated.
Post by: mathx on May 29, 2011, 07:36:43 AM

I'm in Canada. You know what let me check my gas bill cause I may have spoken with my ass lol :p..one moment plz..nope I was correct..I pay $0.14 per cubic meter of gas, but pay only $0.06 in the winter for electricity.



Do you tihnk 1 cu m of gas = $0.06 whatevers of electricity? Need some units please. kWH are fine. its a unit of energy. Throw in efficiency of device after that too (as someone said, gas furnace is
about 40-98%, then there's 300W furnace fan for my 1800 sq ft house, but all of its waste heat goes into the house too, for the most part...)


Title: Re: Calculating heat generated.
Post by: allinvain on May 29, 2011, 07:54:21 AM
In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs.

Where in the world are you?

There is absolutely no comparison between gas and electric heat where I am. I paid about $60 a month to keep a 4000 sq. ft house toasty warm with gas last winter.

I'd be better off burning dollar bills to keep warm than paying for electric heat.

I'm in Canada. You know what let me check my gas bill cause I may have spoken with my ass lol :p..one moment plz..nope I was correct..I pay $0.14 per cubic meter of gas, but pay only $0.06 in the winter for electricity.



You need to check your units.  a cubic metre of gas is a lot more energy than a kilowatt-hour of electricity.

On equal units:

a gigajoule of natural gas (26.3 cubic metres) costs me $4.55 ($0.1725/cubic metre)

a gigajoule of electricity (278 kilowatt-hours) costs me $24.93 ($0.09/kilowatt-hour)

Even using your prices, natural gas is still way cheaper ($16.68 vs. $3.68).

Oooops :P I guess I totally forgot about the total energy content of both sources of energy. So yeah in the end when you take in the total amount of energy required to heat a house with electricity alone natural gas would be cheaper even though on a per minimum unit of consumption basis electricity is cheaper. One can easily get fooled if you don't take the energy content into consideration.

I don't think anyone will realistically use miner heat to warm up the house. I think a smarter solution would be to move mining equipment into a room or area where you can shut off the furnace vents or maybe even open up the windows and let in the cold winter air.


Title: Re: Calculating heat generated.
Post by: mathx on May 29, 2011, 10:23:15 AM


I don't think anyone will realistically use miner heat to warm up the house. I think a smarter solution would be to move mining equipment into a room or area where you can shut off the furnace vents or maybe even open up the windows and let in the cold winter air.

haha, you're missing the point! any money saved by heating your house with your rigs is now LOST to the outside! why not just... HEAT YOUR HOUSE with your rigs?

If the rigs are putting out too much heat however, you could have a distribution issue, and need fans (which cost power too). Better to spread the rigs around the house,
in drafty areas, say under windows ;)

Still you are saving the cost of gas on that electricity only, still going to be 7-10c/kWh in most of the cheaper markets for heating by electricity, and still much more (tho in such markets,
gas tends to be more $ too - there's some friction between gas and electricity prices in each market).


Title: Re: Calculating heat generated.
Post by: allinvain on May 29, 2011, 01:46:01 PM
Hmm I guess, but isn't it going to take a LOT of heat from the miners to reasonably warm up the house. I guess if you can tolerate colder than what you're used to temps during the winter then it's ok.

I think to reasonably heat up a modestly sized house you're going to need to output multiple kilowatts/h of heat. But if you have good insulation you can maybe slowly warm up the house and it will retain the heat for a while.



Title: Re: Calculating heat generated.
Post by: mathx on June 04, 2011, 04:31:51 AM
Hmm I guess, but isn't it going to take a LOT of heat from the miners to reasonably warm up the house. I guess if you can tolerate colder than what you're used to temps during the winter then it's ok.

I think to reasonably heat up a modestly sized house you're going to need to output multiple kilowatts/h of heat. But if you have good insulation you can maybe slowly warm up the house and it will retain the heat for a while.

Super efficient houses use a 1000W heater at intervals for the whole house. Most space heaters are 1200+W and you'd need 5-10 of them for a regular house (1500-2000 sq ft), more for bigger houses, if they're poorly insulated.

Depends on how many rigs yer running.


Title: Re: Calculating heat generated.
Post by: c-rock on June 04, 2011, 04:59:06 AM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.

Umm yes and no. What you're doing is using electricity to heat your home instead of natural gas. In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs. The thing is that you'd have to figure out some way to push all that heat from the miners and circulate it around the house. I wonder if anyone has setup a ghetto rig to push the heat into a furnace's ducts.

I have a fireplace with a heatilator (sp?) circulating system. I suppose I could place the mining rig there and use a video monitor to display a GPU generated fireplace display.  :D


I got my two rigs in the fireplace, dumping the heat out the chimney :-X. 


Title: Re: Calculating heat generated.
Post by: gigabytecoin on June 04, 2011, 06:57:21 AM
I have a feeling that a $200 12k BTU AC is much crappier/warmer than a $400 12k BTU AC... so be careful! I have looked into portable ACs as well and it seems that the less you pay.. the worse quality you receive. As in it's not actually 12k BTUs worth of cold for example.


Title: Re: Calculating heat generated.
Post by: allinvain on June 04, 2011, 07:34:28 AM
Thanks, that's what I'm looking for when using an A/C rated in BTUs.

I imagine in cold climates that the electric used for the system converted to heat would equate to home heat savings.

Umm yes and no. What you're doing is using electricity to heat your home instead of natural gas. In most places I know of electricity is cheaper than natural gas/heating oil so yeah I guess you would be saving $ on heating costs. The thing is that you'd have to figure out some way to push all that heat from the miners and circulate it around the house. I wonder if anyone has setup a ghetto rig to push the heat into a furnace's ducts.

I have a fireplace with a heatilator (sp?) circulating system. I suppose I could place the mining rig there and use a video monitor to display a GPU generated fireplace display.  :D


I got my two rigs in the fireplace, dumping the heat out the chimney :-X. 

 :D kick ass...that's one smart use of the fireplace..




Title: Re: Calculating heat generated.
Post by: allinvain on June 04, 2011, 07:57:17 AM
I have a feeling that a $200 12k BTU AC is much crappier/warmer than a $400 12k BTU AC... so be careful! I have looked into portable ACs as well and it seems that the less you pay.. the worse quality you receive. As in it's not actually 12k BTUs worth of cold for example.

Well, remember the old adage: "you get what you pay for"

Some of those portable ACs are most likely not as efficient as regular in window or central air style ACs. Quote from the consumer reports website

"Dual-hose portables—which have two hoses that vent through a window; one brings air in from the outside to cool the condenser coils, and the other exhausts the hoy, humid room air back to the outside—did a slightly better cooling job than the single-hose models we've previously tested, But their ability to cool fell short of similar-size window units, and they couldn't cool the testing chamber to the desired temperature."