More heat than light? Incandescent vs CFL vs LED

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Originally Posted By: Johnny2Bad
If the area is one that uses supplemental heat ... ie you have a Natural Gas furnace and the lamp is in an area heated by that furnace, then changing to a more efficient bulb will mean you will use more Natural Gas to replace the lost heat provided by the lamp. So you have gained nothing; you reduce one bill and increase another for the same net result.

Ideally you would use incandescents in winter and switch to LEDs when the air temperature is above about 70F, and back to incandescents in the fall. But of course regulators realize no-one will do this, so they ban incandescents and conveniently fail to mention the increase in winter heating load that will result.

As always, it's not the information you get that matters, it's the information held from you that matters.

Excellent.

Not to mention the eye damaging effects and melatonin disruption on sleep patterns caused by LED lights:

https://www.lewrockwell.com/2016/10/joseph-mercola/beware-eye-destroying-lightbulbs/
 
Originally Posted By: edwardh1
the lighting industry should be ashamed of the cfl hoax, "it will last 10 years etc etc.


In the 12 years we've lived here, I've replaced 2 CFL bulbs in the house. Those failed quite early but the others have been going strong. I had incandescents before that, and still do in some fixtures but have replaced dozens so far.

I'll not buy any more CFL and go to LED but still have a healthy stash of the same CFL bulbs that refuse to fail at $0.25 each that I'll use first. The 1 LED bulb we have works well, same colour as the halogen G10 it replaces, but slightly lower light output.
 
Originally Posted By: Rock_Hudstone
Originally Posted By: Johnny2Bad
If the area is one that uses supplemental heat ... ie you have a Natural Gas furnace and the lamp is in an area heated by that furnace, then changing to a more efficient bulb will mean you will use more Natural Gas to replace the lost heat provided by the lamp. So you have gained nothing; you reduce one bill and increase another for the same net result.

Ideally you would use incandescents in winter and switch to LEDs when the air temperature is above about 70F, and back to incandescents in the fall. But of course regulators realize no-one will do this, so they ban incandescents and conveniently fail to mention the increase in winter heating load that will result.

As always, it's not the information you get that matters, it's the information held from you that matters.

Excellent.

Not to mention the eye damaging effects and melatonin disruption on sleep patterns caused by LED lights:

https://www.lewrockwell.com/2016/10/joseph-mercola/beware-eye-destroying-lightbulbs/


You loose all credibility when you reference a quack like Mercola.
 
Originally Posted By: edwardh1
the lighting industry should be ashamed of the cfl hoax, "it will last 10 years etc etc.


Most of mine did...several lasted longer than that.
 
Originally Posted By: hatt
Originally Posted By: Johnny2Bad
LEDs are increasing efficiency at a very good rate ... the units available in five years will generate half the heat for the same light output at those available today, and those are very much advanced over LEDs of the past.

If you lose a light source this morning, you need to replace it today, not five years from now. So use what is available.

It should be noted that light efficiency is based on the assumption that heat is an unwanted side effect of operating the device. If you live in a northern climate, or you have lighting in an area of the home that is unheated but less than 68F, then the heat output is ** wanted ** output, not unwanted output. Thus the least efficient type is now 100% efficient, as both the heat and light are wanted output.

Electrical heating is 95% or better in efficiency. If you have one of the latest super-high efficiency natural gas furnaces you can equal that. Where electric heat is inefficient compared to the most recent Natural Gas heater technology is at the Power Plant, which can be as little as 70% efficient but also could be higher, depending on how your local utility generates electricity. Now it's a matter of your Natural Gas heater (how old is it?) versus your Power Plant (is it nuclear? Very efficient) as far as what is least damaging to "the Planet". Older furnaces can be less than 70% efficient.

If the area is one that uses supplemental heat ... ie you have a Natural Gas furnace and the lamp is in an area heated by that furnace, then changing to a more efficient bulb will mean you will use more Natural Gas to replace the lost heat provided by the lamp. So you have gained nothing; you reduce one bill and increase another for the same net result.

Ideally you would use incandescents in winter and switch to LEDs when the air temperature is above about 70F, and back to incandescents in the fall. But of course regulators realize no-one will do this, so they ban incandescents and conveniently fail to mention the increase in winter heating load that will result.

As always, it's not the information you get that matters, it's the information held from you that matters.
When you're promoting an agenda you can't put out all the information and water down the narrative. Incandescents are always bad all the time. I wonder what the ACTUAL overall energy savings are in a colder climate.


Substantial...simply because heating with electricity is very expensive. It is cheaper to use the cfl for light, and a little more oil or gas for heat.

And, of course, you will never need heat more than 4-5 months of the year, unless you're somewhere like Barrow.
 
Originally Posted By: raytseng
Originally Posted By: Johnny2Bad
LEDs are increasing efficiency at a very good rate ... the units available in five years will generate half the heat for the same light output at those available today, and those are very much advanced over LEDs of the past.

If you lose a light source this morning, you need to replace it today, not five years from now. So use what is available.

It should be noted that light efficiency is based on the assumption that heat is an unwanted side effect of operating the device. If you live in a northern climate, or you have lighting in an area of the home that is unheated but less than 68F, then the heat output is ** wanted ** output, not unwanted output. Thus the least efficient type is now 100% efficient, as both the heat and light are wanted output.

Electrical heating is 95% or better in efficiency. If you have one of the latest super-high efficiency natural gas furnaces you can equal that. Where electric heat is inefficient compared to the most recent Natural Gas heater technology is at the Power Plant, which can be as little as 70% efficient but also could be higher, depending on how your local utility generates electricity. Now it's a matter of your Natural Gas heater (how old is it?) versus your Power Plant (is it nuclear? Very efficient) as far as what is least damaging to "the Planet". Older furnaces can be less than 70% efficient.

If the area is one that uses supplemental heat ... ie you have a Natural Gas furnace and the lamp is in an area heated by that furnace, then changing to a more efficient bulb will mean you will use more Natural Gas to replace the lost heat provided by the lamp. So you have gained nothing; you reduce one bill and increase another for the same net result.

Ideally you would use incandescents in winter and switch to LEDs when the air temperature is above about 70F, and back to incandescents in the fall. But of course regulators realize no-one will do this, so they ban incandescents and conveniently fail to mention the increase in winter heating load that will result.

As always, it's not the information you get that matters, it's the information held from you that matters.


There is an exception to your story and that is if you have a heatpump based heating.
Heatpumps provide much more than 100% efficiency in heat per watt of electricity used by including the outside environment as part of the thermodynamics equations. Most heatpumps should have at a minimum of over 100% efficiency except in the most extreme climates.

If you are doing the thought experiment of switching your light bulb type in the name of efficiency, this doesn't make sense, you should instead think even further outside the box (literally thinking outside the house as a closed system) and jumped to a heatpump based heating solution, which then renders all that busywork of swapping lightbulbs seasonally a moot point.


Heat pumps are not practical in cold climates. I recall seeing that they work poorly if at all below freezing.
 
Originally Posted By: Jarlaxle


Substantial...simply because heating with electricity is very expensive. It is cheaper to use the cfl for light, and a little more oil or gas for heat.

And, of course, you will never need heat more than 4-5 months of the year, unless you're somewhere like Barrow.
That's not the point. The point is that when it's cold the incandescent become more energy efficient because the heat generated becomes a useful byproduct. This must be accounted for when you start talking about nationwide energy policy.
 
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Originally Posted By: hatt
Originally Posted By: Jarlaxle


Substantial...simply because heating with electricity is very expensive. It is cheaper to use the cfl for light, and a little more oil or gas for heat.

And, of course, you will never need heat more than 4-5 months of the year, unless you're somewhere like Barrow.
That's not the point. The point is that when it's cold the incandescent become more energy efficient because the heat generated becomes a useful byproduct. This must be accounted for when you start talking about nationwide energy policy.


That's some pretty good quackery, it's already accounted for in that no one talks about it. It's very inefficient at other times when it's not needed. Notice how with boilers you turn them on when needed and shut them off when you don't. Not too many people go around changing light bulbs with the seasons, it's hard enough to get people to change the batteries in their smoke alarms where the by product of not doing so is death in the case of a fire. And you think they're going to switch light bulbs between seasons? Plus the cost of the bulbs on an hourly basis isn't that cheap and electric is typically 3 times or more what using fossil fuels like gas or oil would cost. It's also not laid out properly, most bulbs are in the ceiling light fixtures and heat rises so you don't get much heat below which is why most electric baseboard is on the floor or forced hot air vents are on the bottom so that hot air can rise and heat the whole room. We can also go on about doing a Manual J calculation and how many bulbs you'll need for the btu's required when the temperature is at -20 outside. How many light fixtures would you need to install to generate enough btu's to meet the housing code, here's it's 68 during the day and 64 at night.

It's basically a non starter which is why I dismiss it with a simple wave of the hand.
 
I think the more fun quackery I found before on the interenet was if you buy tealights in bulk and use those to get a trifecta of Cooking, lighting, and Heating!

There's a psychological urge to think 1) the industry is out to get you and 2) you can outsmart those folks with your good brain (e.g. about half the oil threads).
Thinking you found the holy grail of lightbulbs can e-z bake oven your house for climate control is a bit out there, compared to a device whose sole purpose is to heat the house and where a whole industry and engineers and the free market spent time to develop.

Hey though if it floats your boat go for it.
 
Speaking of quacks, lets not forget this whole business of CLF and LED light bulbs was quietly rammed through Congress and signed into law in 2007 by Bush.

Therefore, it was, and is, a totally political top down authoritarian edit based on the false science of reducing carbon emission to save the world from global warming. Not a free market driven technical advancment.
 
Originally Posted By: raytseng
I think the more fun quackery I found before on the interenet was if you buy tealights in bulk and use those to get a trifecta of Cooking, lighting, and Heating!

There's a psychological urge to think 1) the industry is out to get you and 2) you can outsmart those folks with your good brain (e.g. about half the oil threads).
Thinking you found the holy grail of lightbulbs can e-z bake oven your house for climate control is a bit out there, compared to a device whose sole purpose is to heat the house and where a whole industry and engineers and the free market spent time to develop.

Hey though if it floats your boat go for it.


Something just tells me that he didn't major in the STEM fields. Regular electricity is about 100% efficient in a heating system. Regular light bulbs product light and heat as a byproduct, right there it's less than 100% efficient as opposed to regular electric baseboard heat. Plus most electric baseboard I see is 15 amps at 240 volts, which is basically a double pole breaker and range from 1500-2500 watts. Most light fixtures are just 15 amp single pole so you'd have to do lots of wiring. And you're mostly limited to 120 watt bulbs and those can be a fire hazard in some light fixtures as some are only rated for 60 watts. You'd be better off with a portable 1500 watt heater although those are also fire hazards.
 
Quote:
If the area is one that uses supplemental heat ... ie you have a Natural Gas furnace and the lamp is in an area heated by that furnace, then changing to a more efficient bulb will mean you will use more Natural Gas to replace the lost heat provided by the lamp. So you have gained nothing; you reduce one bill and increase another for the same net result.

Ideally you would use incandescents in winter and switch to LEDs when the air temperature is above about 70F, and back to incandescents in the fall. But of course regulators realize no-one will do this, so they ban incandescents and conveniently fail to mention the increase in winter heating load that will result.

As always, it's not the information you get that matters, it's the information held from you that matters.

Umm.no incandescent is less efficient than natural gas or heat pump.
 
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Originally Posted By: fdcg27
Impressive, but we expect rapid improvements in electronics, which LED lamps are.
More impressive to me is that you actually got into a discussion of lighting efficiency with a seatmate on a commercial flight.
How in blue blazes did that happen?


I'm such a nerd, that's how. Hahahahaha
 
Originally Posted By: Wolf359
Originally Posted By: hatt
Originally Posted By: Jarlaxle


Substantial...simply because heating with electricity is very expensive. It is cheaper to use the cfl for light, and a little more oil or gas for heat.

And, of course, you will never need heat more than 4-5 months of the year, unless you're somewhere like Barrow.
That's not the point. The point is that when it's cold the incandescent become more energy efficient because the heat generated becomes a useful byproduct. This must be accounted for when you start talking about nationwide energy policy.


That's some pretty good quackery, it's already accounted for in that no one talks about it. It's very inefficient at other times when it's not needed. Notice how with boilers you turn them on when needed and shut them off when you don't. Not too many people go around changing light bulbs with the seasons, it's hard enough to get people to change the batteries in their smoke alarms where the by product of not doing so is death in the case of a fire. And you think they're going to switch light bulbs between seasons? Plus the cost of the bulbs on an hourly basis isn't that cheap and electric is typically 3 times or more what using fossil fuels like gas or oil would cost. It's also not laid out properly, most bulbs are in the ceiling light fixtures and heat rises so you don't get much heat below which is why most electric baseboard is on the floor or forced hot air vents are on the bottom so that hot air can rise and heat the whole room. We can also go on about doing a Manual J calculation and how many bulbs you'll need for the btu's required when the temperature is at -20 outside. How many light fixtures would you need to install to generate enough btu's to meet the housing code, here's it's 68 during the day and 64 at night.

It's basically a non starter which is why I dismiss it with a simple wave of the hand.
I never said heating a house with light bulbs was smart. Only that you have to factor that into any energy calculations.
 
Originally Posted By: Wolf359
Originally Posted By: raytseng
I think the more fun quackery I found before on the interenet was if you buy tealights in bulk and use those to get a trifecta of Cooking, lighting, and Heating!

There's a psychological urge to think 1) the industry is out to get you and 2) you can outsmart those folks with your good brain (e.g. about half the oil threads).
Thinking you found the holy grail of lightbulbs can e-z bake oven your house for climate control is a bit out there, compared to a device whose sole purpose is to heat the house and where a whole industry and engineers and the free market spent time to develop.

Hey though if it floats your boat go for it.


Something just tells me that he didn't major in the STEM fields. Regular electricity is about 100% efficient in a heating system. Regular light bulbs product light and heat as a byproduct, right there it's less than 100% efficient as opposed to regular electric baseboard heat. Plus most electric baseboard I see is 15 amps at 240 volts, which is basically a double pole breaker and range from 1500-2500 watts. Most light fixtures are just 15 amp single pole so you'd have to do lots of wiring. And you're mostly limited to 120 watt bulbs and those can be a fire hazard in some light fixtures as some are only rated for 60 watts. You'd be better off with a portable 1500 watt heater although those are also fire hazards.
Appears you didn't major in reading comprehension.
 
Neither CFL nor LED are efficient since 85-to-90% of the energy is wasted as heat. We do have more-efficient bulbs, but they are single color sources like sodium lamps (yellow). They waste 75% as heat.
Quote:
Electrical heating is 95% or better in efficiency. If you have one of the latest super-high efficiency natural gas furnaces you can equal that. Where electric heat is inefficient compared to the most recent Natural Gas heater technology is at the Power Plant, which can be as little as 70% efficient

I'm wondering where you get natural gas is 95%? I think you forgot to take into account fuel transmission losses from the well to the tanker to the pipes & finally your home. (Also wouldn't a power plant have a better CNG burner than you have? Almost certainly.)

Greenercars.org compares a CNG Civic versus a Hybrid Civic. They found the CNG is less clean, due to burning more energy & also the fuel transmission losses.
 
Originally Posted By: veryHeavy
(Also wouldn't a power plant have a better CNG burner than you have? Almost certainly.)


Power plants have to have a thermodynamic cycle to get electricity out of them, "burner efficiency" is a term that in and of itself makes no sense whatsoever.

"Burner efficiency" relates to unintended reactions, or lack thereof, such as incomplete combustion, or CO, NOx, HC, whatever, and it's in the really high 90s...

But due to a thermodynamic cycle to extract energy, the overall CONVERSION efficiency is very low compared to home heating.

Brayton Cycle (Gas Turbines) top out around 35-40%.
CCGT (Brayton with a boiler/steam turbine on the back end) top out around 55-60%.
Rankine cycle (boiler and steam turbine) top out at the low 40s.

(That's all LHV, as you can't let the flue gasses condense)

So YES, heating your house with NG, using any reasonable method is going to be more efficient than burning the gas at a power station.

That's why we should be using coal/nukes for power, they aren't that useful at heating your home, as the fuel transport is a pain...

Using electric Resistance heating should be limited, as even at virtually 100%, the power plant at the other end is far from that.

As to the premise on incandescent heating, a neighbour used her halogen cooktop as a means of heating her kitchen during one of our more miserable winters...didn't end well at all.
 
Originally Posted By: hatt
Originally Posted By: Wolf359
Originally Posted By: hatt
Originally Posted By: Jarlaxle


Substantial...simply because heating with electricity is very expensive. It is cheaper to use the cfl for light, and a little more oil or gas for heat.

And, of course, you will never need heat more than 4-5 months of the year, unless you're somewhere like Barrow.
That's not the point. The point is that when it's cold the incandescent become more energy efficient because the heat generated becomes a useful byproduct. This must be accounted for when you start talking about nationwide energy policy.


That's some pretty good quackery, it's already accounted for in that no one talks about it. It's very inefficient at other times when it's not needed. Notice how with boilers you turn them on when needed and shut them off when you don't. Not too many people go around changing light bulbs with the seasons, it's hard enough to get people to change the batteries in their smoke alarms where the by product of not doing so is death in the case of a fire. And you think they're going to switch light bulbs between seasons? Plus the cost of the bulbs on an hourly basis isn't that cheap and electric is typically 3 times or more what using fossil fuels like gas or oil would cost. It's also not laid out properly, most bulbs are in the ceiling light fixtures and heat rises so you don't get much heat below which is why most electric baseboard is on the floor or forced hot air vents are on the bottom so that hot air can rise and heat the whole room. We can also go on about doing a Manual J calculation and how many bulbs you'll need for the btu's required when the temperature is at -20 outside. How many light fixtures would you need to install to generate enough btu's to meet the housing code, here's it's 68 during the day and 64 at night.

It's basically a non starter which is why I dismiss it with a simple wave of the hand.
I never said heating a house with light bulbs was smart. Only that you have to factor that into any energy calculations.


Like I said, I don't think you're from the STEM field. That's what a manual J calculation does, it's a heat loss calculation. If you did the math, the heat from a light bulb is negligible. That's why it's not a factor for all the reasons I mentioned earlier.
 
Originally Posted By: Shannow
Originally Posted By: veryHeavy
(Also wouldn't a power plant have a better CNG burner than you have? Almost certainly.)


Power plants have to have a thermodynamic cycle to get electricity out of them, "burner efficiency" is a term that in and of itself makes no sense whatsoever.

"Burner efficiency" relates to unintended reactions, or lack thereof, such as incomplete combustion, or CO, NOx, HC, whatever, and it's in the really high 90s...

But due to a thermodynamic cycle to extract energy, the overall CONVERSION efficiency is very low compared to home heating.

Brayton Cycle (Gas Turbines) top out around 35-40%.
CCGT (Brayton with a boiler/steam turbine on the back end) top out around 55-60%.
Rankine cycle (boiler and steam turbine) top out at the low 40s.

(That's all LHV, as you can't let the flue gasses condense)

So YES, heating your house with NG, using any reasonable method is going to be more efficient than burning the gas at a power station.

That's why we should be using coal/nukes for power, they aren't that useful at heating your home, as the fuel transport is a pain...

Using electric Resistance heating should be limited, as even at virtually 100%, the power plant at the other end is far from that.

As to the premise on incandescent heating, a neighbour used her halogen cooktop as a means of heating her kitchen during one of our more miserable winters...didn't end well at all.


Well it's been a long time since I worked at a cogen power plant. But basically, it didn't use a CNG burner, it was basically two combustion turbines with a steam generator. I seem to remember it burned about 60-65k decatherms per hour depending on the weather, hot weather could be as bad as 260 megawatts and cold weather was up to 330 megawatts or more. The turbines were basically jet engines, the exhaust went into the steam turbine and that was also connected to a generator. It was connected to the grid with 360kv lines. Took about 5-7 megawatts just to run the plant if the turbines were off line due to maintenance. A certain percentage of the steam was used for another process hence the term co-generation. And yes, the efficiency of the generators were about 33% just from power sent to the grid vs the btu in the gas burned. Then you have transmission line losses, cost of transmission etc so even though electric heat is about 100% efficient, the btu input to generate that electricity makes it very inefficient. At least for gas. Now if nuclear had turned out to be too cheap to meter, then electric heat might work in some other areas. I think some areas that have lots of hydro power have really cheap costs per kilowatt rates so that it's cheaper to use electric heat than gas.
 
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