Thursday, November 26, 2009
Sunday, November 22, 2009
Condensing Boiler vs Geothermal Heat Pump: Cheap Heat Surprise
Many a home owner on the look out for something new to replace an old, inefficient heating system probably knows a thing or two about the exceptional efficiency of geothermal heat pumps. But few people are aware of the new 95% efficient condensing boilers fueled by natural gas.
While a geothermal heat pump’s 350% efficiency far outstrips that of a 95% efficient condensing boiler, higher efficiency ratings don’t always mean lower heating costs.
It’s only when the cost of fuel is factored in can you determine the actual cost of heating for each system. In the example below the cost to produce 100,000 Btu will be used to compare the systems.
Since a geothermal heat pump runs on electricity measured in kilowatt hours (kWh), and a condensing boiler is fueled by natural gas measured in therms, it’s necessary to convert kWh of electricity into “therms” to make an accurate comparison.
One therm of gas produces 100,000 Btu so we need to know how many kWh of electricity it would take to produce 100,000 Btu. Since one kWh = 3,413 Btu it would require 29.3 kWh to produce 100,000 Btu, or one “therm” of electricity.
Here in New England electricity goes for $0.143 per kWh. So a “therm” of electricity would cost $4.19 (29.3 x $0.143). A therm of natural gas, according to National Grid, retails for $0.78.
The next step is to apply each appliance’s efficiency to its respective fuel price. But it’s not as simple as multiplying the fuel price by the percentage of efficiency (95% or 350%). Instead you would use the coefficient of each percentage as a constant to keep the comparison apples to apples.
The condensing boiler efficiency is 95% therefore the coefficient is 1/.95 or 1.05
The geothermal heat pump efficiency is 350% so the coefficient would be 1/3.50 or .29
Finally, the efficiency coefficient is multiplied by the cost per therm of fuel for each system to determine which one produces 100,000 Btu of heat for the least amount of money.
Geothermal Heat Pump: .29 x $4.19 = $1.22 per 100,000 Btu
Condensing Boiler: 1.05 x $0.78 = $0.82 per 100,000 Btu
The surprising results show that even though a geothermal heat pump is 3½ times more efficient than a condensing boiler the heat it produces is 49% more expensive.
This paradox is brought about by recent low natural gas prices and the high cost of electricity in New England.
Depending on where you live, utility rates will vary from the ones used in this example but it should be simple enough to substitute local rates for the ones here to make your own comparisons.
Find out which condensing boilers contractors love at Best High Efficiency Condensing Boilers.
While a geothermal heat pump’s 350% efficiency far outstrips that of a 95% efficient condensing boiler, higher efficiency ratings don’t always mean lower heating costs.
It’s only when the cost of fuel is factored in can you determine the actual cost of heating for each system. In the example below the cost to produce 100,000 Btu will be used to compare the systems.
Since a geothermal heat pump runs on electricity measured in kilowatt hours (kWh), and a condensing boiler is fueled by natural gas measured in therms, it’s necessary to convert kWh of electricity into “therms” to make an accurate comparison.
One therm of gas produces 100,000 Btu so we need to know how many kWh of electricity it would take to produce 100,000 Btu. Since one kWh = 3,413 Btu it would require 29.3 kWh to produce 100,000 Btu, or one “therm” of electricity.
Here in New England electricity goes for $0.143 per kWh. So a “therm” of electricity would cost $4.19 (29.3 x $0.143). A therm of natural gas, according to National Grid, retails for $0.78.
The next step is to apply each appliance’s efficiency to its respective fuel price. But it’s not as simple as multiplying the fuel price by the percentage of efficiency (95% or 350%). Instead you would use the coefficient of each percentage as a constant to keep the comparison apples to apples.
The condensing boiler efficiency is 95% therefore the coefficient is 1/.95 or 1.05
The geothermal heat pump efficiency is 350% so the coefficient would be 1/3.50 or .29
Finally, the efficiency coefficient is multiplied by the cost per therm of fuel for each system to determine which one produces 100,000 Btu of heat for the least amount of money.
Geothermal Heat Pump: .29 x $4.19 = $1.22 per 100,000 Btu
Condensing Boiler: 1.05 x $0.78 = $0.82 per 100,000 Btu
The surprising results show that even though a geothermal heat pump is 3½ times more efficient than a condensing boiler the heat it produces is 49% more expensive.
This paradox is brought about by recent low natural gas prices and the high cost of electricity in New England.
Depending on where you live, utility rates will vary from the ones used in this example but it should be simple enough to substitute local rates for the ones here to make your own comparisons.
Find out which condensing boilers contractors love at Best High Efficiency Condensing Boilers.
Friday, November 20, 2009
Which Is Safer: The Electric Space Heater or Electric Fireplace?
According to the National Fire Protection Assoc. (NFPA) heating equipment was the second leading cause of home fires and home fire deaths.
The heating equipment category includes central heating, fixed and portable space heaters and wood stoves. Of these, fixed space heaters (wall mounted or freestanding propane heaters) accounted for 17% of the fires and 28% of the civilian deaths.
Portable heaters (propane and electric) caused far fewer fires, only 8% of the total, but accounted for 46% of the total deaths resulting from heating equipment fires.
So how can this be with increasingly stringent space heater manufacturing safety standards?
The best answer to this question comes from Fire Chief Eric Chichester of Parkersburg, WV, a state which had 6 space heater related deaths in October: “The problem isn't really with the space heater itself, but with misusing it and leaving it unattended.”
If misuse of the space heater and not the space heater itself is the cause of fires, which type of heater would be prone to misuse more frequently; an electric fireplace or space heater?
Although far fewer electric fireplaces are sold in North America than small space heaters, close tracking of the occurrences of space heater fires so far this season has yet to reveal an instance where an electric fireplace was a contributing factor.
This suggests that people are less likely to misuse an electric fireplace and therefore the electric fireplace is safer. But this begs the question; why are electric fireplaces misused less than ordinary space heaters?
The answer to this lies in the overall size and design of the electric fireplace. The placement of the electric firebox in the middle of a 4 foot wide unit creates a natural buffer zone on either side between it and draperies, furniture or bedding that might be in the room.
By keeping flammables away from the heater you will practically eliminate the number one cause of space heater fires.
An electric fireplace is also regarded as a beautiful piece of furniture which makes it less likely that bags of clothing, boxes, etc. would be piled in front of it – never mind blocking the heat source.
The perception that an electric fireplace, by virtue of its size, is more powerful than it really is probably tempts fewer people to plug it into an overloaded extension cord. Plugging an electric fireplace into its own wall socket all but eliminates another potential fire hazard.
Finally, the flame display, crackling fire sound effect, and humming of the blower serve as a constant reminder the fireplace is running and makes it less likely it would be left on when the house is unoccupied.
Rather than trying to pit the electric fireplace against the electric space heater, the real purpose of this article is to remind everyone that any space heater can be a safe space heater if you keep it at least 3’ away from combustibles, don’t use an extension cord, and remember to turn it off when you go to bed and leave the house.
Electric fireplaces are beautiful, fun and efficient. Find exactly what you’re looking for in a price range you can afford at Sam’s Guide to Electric Fireplaces.
The heating equipment category includes central heating, fixed and portable space heaters and wood stoves. Of these, fixed space heaters (wall mounted or freestanding propane heaters) accounted for 17% of the fires and 28% of the civilian deaths.
Portable heaters (propane and electric) caused far fewer fires, only 8% of the total, but accounted for 46% of the total deaths resulting from heating equipment fires.
So how can this be with increasingly stringent space heater manufacturing safety standards?
The best answer to this question comes from Fire Chief Eric Chichester of Parkersburg, WV, a state which had 6 space heater related deaths in October: “The problem isn't really with the space heater itself, but with misusing it and leaving it unattended.”
If misuse of the space heater and not the space heater itself is the cause of fires, which type of heater would be prone to misuse more frequently; an electric fireplace or space heater?
Although far fewer electric fireplaces are sold in North America than small space heaters, close tracking of the occurrences of space heater fires so far this season has yet to reveal an instance where an electric fireplace was a contributing factor.
This suggests that people are less likely to misuse an electric fireplace and therefore the electric fireplace is safer. But this begs the question; why are electric fireplaces misused less than ordinary space heaters?
The answer to this lies in the overall size and design of the electric fireplace. The placement of the electric firebox in the middle of a 4 foot wide unit creates a natural buffer zone on either side between it and draperies, furniture or bedding that might be in the room.
By keeping flammables away from the heater you will practically eliminate the number one cause of space heater fires.
An electric fireplace is also regarded as a beautiful piece of furniture which makes it less likely that bags of clothing, boxes, etc. would be piled in front of it – never mind blocking the heat source.
The perception that an electric fireplace, by virtue of its size, is more powerful than it really is probably tempts fewer people to plug it into an overloaded extension cord. Plugging an electric fireplace into its own wall socket all but eliminates another potential fire hazard.
Finally, the flame display, crackling fire sound effect, and humming of the blower serve as a constant reminder the fireplace is running and makes it less likely it would be left on when the house is unoccupied.
Rather than trying to pit the electric fireplace against the electric space heater, the real purpose of this article is to remind everyone that any space heater can be a safe space heater if you keep it at least 3’ away from combustibles, don’t use an extension cord, and remember to turn it off when you go to bed and leave the house.
Electric fireplaces are beautiful, fun and efficient. Find exactly what you’re looking for in a price range you can afford at Sam’s Guide to Electric Fireplaces.
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