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My basement is COLD in summer and COLDER in winter. Even it summer it feels good to cozy up to my mining machine. I haven't ordered a: Kill A Watt Electricity Usage Monitor, yet. I'm wondering how a mining machine compares to a space heater and also oil heaters.

These heaters usually run between 500 and 1500 watts, and based on using them before, the space heaters are not very efficient, the oil heaters probably produce more heat for less wattage. How does a mining machine stack up against a space heater and oil heater?

Are we getting over and saving a bit of money in the winter?

Of course most of us would not run the heater 24/7, but lets just ignore that for the time being.

In my experience the miners add just enough heat that its never cold. You wont be freezing but you wont be toasty either. Power wise, how can you even compare? Miner is negative cost as a heater.

Maybe you could get a bathtub next to your rig and try to heat the water with exhaust air from your GPUs. It wouldn't get any hotter than you GPUs are so no chance for boiling water for cooking or something like that. Maybe you could fry an egg on your graphics card if you were to replace the heat sink with a flat copper plating :P

Well I know I'm going to pay. But it feels like my miner is producing close to the heat of a space heater set on low (500 watts), if that is the case, then we are "getting over" (sorry for the use of USA slang) a little in winter time because I'm heating my room and generating bitcoins at the same time. If I'm just running a heater I get nothing but heat.

I don't expect much savings here, but I have heard other miners talk about their mining rigs making their rooms nice and warm in the winter (and too damn hot in the summer!)

LOL!

NO!!! All electric heaters are exactly 100% efficient. 1000W of electricity in is 1000W of heat out.

Now if you were to get a window air conditioner (heat pump) and put it in the window backwards then you might put 1000W of electricity in and get 2000W or more of heat out. But a window AC won't come on once the outside temperature falls below a certain point.

If you make enough bitcoins to pay the electric bill then you can heat for free!

We are definitely going to see some serious increase of network-hashrate in winter...  :o

A mining machine is almost as efficient in converting electricity to heat as a space heater since almost of the energy used in semiconductors are converted to heat. It just loses out mostly due to the fans and other mechanical parts. And it would probably work better since the fans in the machine will help spread the heat around the room better.

With this and your BTC guild posts, we can safely conclude you really are mad :D

MY mining machine used around 300W, My small fan heater uses around 190W and puts out 3X as much heat 5X faster. My oil heater uses 80W takes a hour to get up to the same temp but once its there it turns off and on saving power.

So stealing, people conspiring, air conditioners and heat pumps don't exist?

All these exists... just not an air conditioner that outputs 2000W or more with an input energy of 1000W in a room with a sub 500W mining machine. :D

Especially not when it is installed backwards with the radiator facing the inside of the room and the air vents facing outdoors during winter.

Of course I'm not a HVAC expert so feel free to illustrate technically how your perpetual motion aircon setup works :D

It doesn't lose out due to anything. Precisely 100% of the energy that the machine uses becomes eat. Even the energy that goes to fans turns into kinetic energy of molecules, which is pretty much the definition of heat. The friction in the bearings, the current through the wires, it's all heat.

If you don't see why this must be, consider a computer locked inside a room. All that can pass into or out of the room is electricity (through wires) and heat (through the walls of the room). Now imagine we let the room sit until it reaches an equilibrium. All that is going into the room is electric energy and all that is leaving the room is heat. If you assume the conversion wasn't a perfect 100% electricity-to-heat, that would mean something would be either building up in the room or being depleted from the room. But that would contradict our assumption that we let the room sit until it reached an equilibrium.

True and agreed, I got too focused on the superficial appearance rather than the fundamental nature :D

Not to detract from Joel's post, but to add to the silly side - obviously you should put your miners outside blowing onto the AC unit so it doesn't get cold.

On the proper side - I am enjoying winter and the rigs keep the place nice and tropical.

This is so stupid Xephan how can say I am just making up everything when you don't even know how a heat pump works.

If you buy one with a COP of 3 it may use 5,000W and put 15,000W (52,000 BTU) of heat in to your house.

Nope. Try again

An air conditioner most definitely CAN output more heat than the power it consumes if placed in a window "backwards".  It's called a heat pump, and it gives you more heat than just using that same electricity to make heat. Good heat pumps can have a COP (coefficient of performance) of over 6! So every watt it uses concentrates 6 watts of heat from one place and moves it to another.  The highest I've seen is 7-something, which blows my mind.

Indeed. But even in the worst case such a device is still more efficient than resistive heating.  This of course only applies to air-source heat pumps. Water-source are dependent only on the temperature of the water supply which stays relatively consistent year round.

Yes and no, and while air is still a gas, it has lots of kinetic energy.   Moving from 10C to 0C (50f to 32f) only extracts about 5% of the energy available.  Move it to -100C and it will choke.  Remember also that AC units (heating and cooling) are normally designed for their environment, that's why some will work happily at -15C and others will have iced up.

Flip side, exchanging energy from a hot room to an even hotter outside is the same principle.

My 1.1G/hash miner uses 750W's and generates A LOT of heat. The bright side of running it is that when its mining bitcoin its gaining more then it costs to operate. Hence the heat is free (kinda). about 10 of these should keep any 1200 ft home worm any time of year.

I have a hard time believing that all electric heaters are 100% efficient but I'm sure it's close.

As for a miner, your power supply might be 20% efficient (at generating heat), but then you have the efficiency of the other components to take into account.  I've worked with servers that put out enough heat to rival a space heater.

It's called conservation of energy!

When a machine uses 1000W of electricity it will put out 1000W of heat. If it puts out more then you have a "free energy machine" or "perpetual motion machine". If it puts out less then you have violated the conservation of energy rule just as much.

If you have a 1000W electric motor that is 80% efficient that is running a fan, then 200W of heat is going to be made by the motor and 800W of heat is going to be created in the surroundings by the friction of the air blowing past everything. It will add exactly 1000W of heating to the room it is in.

A computer that is using 1000W will add exactly 1000W of heating to the room that it is in. A space heater that uses 1000W will put 1000W of heat in the room.

A radio station that is 1000W might make 400W of heat and 600W of energy may be radiated out in to the world and in to space. It will create heat eventually when it hits something like the side of a mountain.

An air conditioner (heat pump) is moving heat from one side to the other. It cools down the air going through one side and then puts that energy it took out of that air in to a liquid/gas which goes through some pipes and then it goes through the hot side which adds energy to the air on the hot side by heating it up when it goes through. All the heat from the electric motor, compressor and friction comes out as heat on the hot side in addition to the heat it took out of the cold side. So a heat pump will never put out less heat than the electricity it is using.

The noise will be a bit of a nuisance with a miner running in every room. :)

Yeah 'a bit'. I don't know about you but I can't sleep when all I hear is the blipping sound of the hard drive's needle moving in my otherwise silent htpc.

It seems that I was mistaken that "window air conditioner" aren't designed to be used as a heat pump and that those which are, are known as reverse cycle air conditioner and these are installed the normal way, rather than reversing them.

So is it true and a common thing that window air conditioner units sold in the states are also effective heat pumps when installed reversed? This is the part I'm skeptical about since a quick look up indicates that heat pumps have to be designed specifically for the temperature ranges desired or their efficiency drops rapidly. So it seems that using a window air conditioner not designed for such a purpose would result in even worse performance.

There are two types of air conditioning, refrigerated (a kind of heat pump) and the traditional evaporative.

Refrigerated uses gas phase change (inside a sealed cycle) to move heat from indoors to outdoor (or vis versa, if run as a heater).

Evaporative also uses phase change (water evaporation). Air is blown over a wet surface, the water evaporated (change phase) taking heat out of the air, before it enters the room. Requires dry air for the water to evaporate into, so doesn't  work in humid condition. This is the same principle as the human body uses cools itself by sweating (or "glowing" if you're a woman).

An unmodified, consumer product window AC unit would make a terrible heat pump, even installed reversed.  However, modifications are possible if you know what you are doing.  Probably more cost effective to buy a unit designed to do it to start with.

Thermodynamic fallacies like some expressed in this thread are hard to overcome. It still is impossible to convince my mother that turning out the lights is not necessary in winter, when the light bulbs are just doing the same job as the resistive electric furnace running at 3000W, eventually converting every bit of electricity they use into heat.

Not related to anything posted yet - when looking for a space heater as a space heater, there is human comfort factor that is also important. Humans like to be 37C. If we lose heat faster than we generate it, we feel cold. The thermal conductivity of the medium affects how cold we feel; for example 25C water removes heat from our bodies much faster than 25C air, so a 25C swimming pool is cold on a 25C day. Moving air also does the same thing, while my computer may be blowing 30C air on my legs, it feels cold because it is removing more heat from my body that cooler, but more stagnant, air would be.

The best space heaters are those that direct very hot air right at you. I have a Pelonic ceramic heater that puts out a slow flow of air at a constant 125C (only the fan speed changes when adjusting it from high to low, the ceramic element 'wants' to be 125C, and the element resistance drops quickly below that temperature). That is much better than a space heater that blows a lot of 35C air at me from across the room, because although they may both be using 1500W, one is removing heat from my body.

I think you need to re-read the wattage labels on those heaters. Your TV likely puts out more heat than 190 watts.

I live in a very cold country too, and our stupid politicians decided to ban traditional energy wasting light bulbs forcing people to buy those new expensive energy saving devices. Apparently they didn't realize, that the energy is not really saved, but moved to increased heating costs.

But some of the light escapes through the windows!!!

Same here. Incandescent bulbs are banned and electric heaters are not. I think I should relabel light bulb packages and start selling 100W electric heaters that emit light.

 :o :o :o

You just killed the Physics and the laws of the thermodynamic do you know?? The conservation of energy and whatelse  :o

100W Heaters with Ultra-Bright in-operation indicators
Ensures you won't leave home without realizing your heater's on ;)

I personally can't wait for winter.
I live in central Florida so the summer has been brutal ~97f every day.
Mining has been pretty costly. BUT. When it's gets to around nov/dec I'm looking at enough heating from my machine to not have to worry about central air. ( it's gets to be about 60f at night. But when you used to the climate. That's pretty damn cold)

That is an amazing idea!

It's probably worth a try if you don't pay for electricity. Scenarios include apartments in which you don't pay for utilities and unusually oblivious or generous neighbors.

I live in Alaska and my house, my boat & the immediate environment off the garage are now heated with 15KW of bitcoins per hour. :)

Personally my suggestion is to go for room heaters with minimum cost which are available in market. As mining costs more,going for these types of equipments can help you more.

Regards.



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Makes no sense. If you stop mining bitcoin you can still use the hardware for scientific computing. And the expense will be the SAME than with the room heater. With the added plus that you are doing something useful.