Heat: Fuel Oil vs Propane vs Electric

[Carl_NH]

12 month average. I can hit $400+/month in the winter depending how cold and how windy.

Hi sdkubota,

At $.06 / KWH and $170 per month, thats roughly 2800KWH / month. Here in the northeast 2800KWH @ $.20 KWH would cost $560 per month! And if your bill goes up to $400 some months well, it would be $1500 here.

We will stick with oil for heat and hot water and electric - which is $3K per year total or $250 for heat and electric per month for 2800SF.

Oaktree,

Yes, when we looked at propane I only considered buying a 800 gal tank (enough to buy once for most of the winter) so we were not tied into one supplier for a long time.

 

[MasseyWV]

We heat with electric, and it sucks. Propane is used for emergencies, and if that runs out... anything that will burn is fair game.

 

[DKCDKC]

We have noticed that we can turn on the heat pump in the morning and heat the house to 73-75 and turn it off for the rest of the day. We might have to turn the heat pump on early in the evening to heat the house back up but that will be it. This is not as good as using the wood stove but it is working and we are comfortable.

I have seen strong research by EPRI and DOE that says turning a heat pump off and on during a day actually increases the total electric consumption. If temperatures drop more than a few degrees, the HP will call for expensive electric resistive backup and the total consumption will rise drastically. They recommend just turning it down a few degrees - if you must - but never shutting it off. They actually say running it constantly at the lowest comfortable temperature is the best way to save. Apparently the HP has to be off for more than a full day to have any hope of actually saving.

 

[aczlan]

I have seen strong research by EPRI and DOE that says turning a heat pump off and on during a day actually increases the total electric consumption. If temperatures drop more than a few degrees, the HP will call for expensive electric resistive backup and the total consumption will rise drastically. They recommend just turning it down a few degrees - if you must - but never shutting it off. They actually say running it constantly at the lowest comfortable temperature is the best way to save. Apparently the HP has to be off for more than a full day to have any hope of actually saving.

Our heating guy says the same thing about the hot water/radiator system in the house. If you drop the tamp by more than 3-4 degrees for part of the day (or just shut it off for part of the day), you burn more fuel bringing everything back up to temperature than you would if you had just dropped it 2 degrees.

Aaron Z

 

[jejeosborne]

Our heating guy says the same thing about the hot water/radiator system in the house. If you drop the tamp by more than 3-4 degrees for part of the day (or just shut it off for part of the day), you burn more fuel bringing everything back up to temperature than you would if you had just dropped it 2 degrees.

Aaron Z

Not sure this is true. All the BTUs stayed inside your conditioned space. Only losses in a combustion setup is what goes out the flue. Electric HP is using twice or 3 times the energy when using the resistant coils as the source rather than the HP. Setback thermometers should be used on combustion systems as drastic as possible in my mind. It is all about differential temps between the inside and outside.

 

[aczlan]

Not sure this is true. All the BTUs stayed inside your conditioned space. Only losses in a combustion setup is what goes out the flue. Electric HP is using twice or 3 times the energy when using the resistant coils as the source rather than the HP. Setback thermometers should be used on combustion systems as drastic as possible in my mind. It is all about differential temps between the inside and outside.

Good point.

Aaron Z

 

[GPintheMitten]

When I had the groundwater HP, I shut the breaker off for the resistance coils backup heat unless I left town. Even in cold Michigan winters, the HP always kept up.

The reason I did this was because sometimes we would adjust the thermostat, and I didn't want the resistance kicking in. But we did not rutinely use setbacks.

 

[jejeosborne]

When I had the groundwater HP, I shut the breaker off for the resistance coils backup heat unless I left town. Even in cold Michigan winters, the HP always kept up.

The reason I did this was because sometimes we would adjust the thermostat, and I didn't want the resistance kicking in. But we did not rutinely use setbacks.

One of the luxuries of ground source vs air source. I have the carrier infinity system air source and it allows me to determine a lockout temperature which locks out the backup unless the outside air temperature is below a certain temp. I have mine set at 25 degrees. Air source units really loose efficiency quickly below 25.

 

[Turbys_1700]

The house I live in was built by my grandfather in 1953...
1450 sq. ft. brick rancher with full basement...
The original heat source was an oil circulatory unit sitting in the hall way close to the bath room...
Around 10 years later or so my grandfather put in an oil furnace...
When I moved into the house in 1985 we utilized window air conditioners and the oil furnace...
Around 1994 or so Duke Energy had a promotion to convert current homes to heat pumps...
We had insulation blown in the side walls, ceiling, and basement in addition to installing a heat pump...
I can attest to the efficiency of the heat pump here in NC...
My house is over 60 years old and my utility bill runs around $2000 per year...
I think that our electric rates are in the 9.3 cents per KWH range...
That is total cost...
I am basically saving the cost of 700 gallons of fuel oil every year...
Not chump change...

 

[DKCDKC]

Heat pumps are efficient because they don't create heat, just move it around. However, the harder they have to work to pull heat out of cold outside air, the more power they use. A dual-fuel system is almost always better than a straight electric HP, geo like mine or not. Almost any energy is cheaper than the resistive electric used as backup. In an earlier house I had with oil heat, I replaced the central AC with a heat pump, but without even putting in the backup - because I had oil. In a dual fuel setup, when the system calls for backup, it simply fires up the oil. Worked great.

My current geo HP system has a much lower temp at which it kicks in backup - and is a zoned system set to keep rooms like the bedroom and spare room cooler. I have the backup for when I'm not home, but simply use a small woodstove otherwise. A small stove in a almost 3,000 sq ft ranch provides all the heat needed to stave off backup resistive at least down to 6 degrees, the coldest experienced in the last 12 years anyway. Since we almost never get colder temps here, that's enough.