I only save $0.50 a day by burning wood?

[LakeFall]

I have an energy monitoring system and wanted to see how much energy I save burning wood. I picked 2 cold days this week with similar daytime temperatures. I have a LP furnace that kicks on under about 20deg or so therefore I only ran 12 hours during the day as I have no way to measure LP consumption. For those 12 hours I kept he insert well fed and at max air intake and fan speed. Active Zone temp needle was pointing straight up. I was surprised to see it only saved $0.50. Any input (other than maybe a larger sample size of days) on what I'm doing wrong here? I have a BK Ashford 25 and for wood burning days, I have a circulate mode on the AH that allows for a min amount of time the AH will run every hour, in this case 30 minutes. House is approx 2300 sq ft.

Date	21-Jan	22-Jan
Wood heat?	12 hours of wood burn	No
Daytime High/Low	28/19	30/21
Heat Pump kWh	17.923	21.019
Air Handler kWh	7.288	9.813
Est. stove fan 60W@12hrs (kWh)	0.72	N/A
Total kWh	25.931	30.832
Cost per kWh	$0.11	$0.11
Cost per day
Savings

[td]

$2.85​

[/td][td]

$3.39​

[/td]​

[td]

$0.54​

[/td]​

 

[JamieW]

Strange that your heat pump only used about 15% less during that time. How did the heat output feel from the stove? Was the area it’s in a lot warmer than without it burning? If your heat pump is using that amount of power still I would assume your AH unit is running anyway without having to force it to run every hour for 30 mins? At those temps I would assume your heat pump would not need to run at all with the stove firing at max output as described.

 

[Rickb]

its hard for me to compare because my stove is in the finished basement. No stove the basement is 60-63. Stove running its 70 - 72. Its our primary living area(IE Computer, TV). The main floor is getting some and the heat runs a lot less, but i like it colder to sleep so i dont want it so hot up there. Seemes odd that you would get those kinda results unless you set the temps lower when not running wood.

 

[30WCF]

I’m not too far from you. Tuesday was very overcast and breezy all day. Dark and damp, and it snowed starting around 5pm, off and on, for most of the night.

Wednesday it was blue skies and sun shine as soon as the sun came up. Our snow in Greensboro was gone for the most part by 10am just because the sun was out. It was still cold, but the sun was out.

My house just heats better when I get solar gain from the sun, especially if I open the blinds and exterior door and let the sun come in through the windows and storm door. Warms those hardwood floors right up.

 

[stoveliker]

Are you sure you are operating the insert properly? Is the bypass closed?

Also, do your ducts go through the attic?

 

[EbS-P]

So many variables. But with newer heat-pumps in our climate they are hard to beat. I imagine if you logged the temp of the basement you would see it was much warmer.

I am wondering when you say max air on the stove, how often were you loading it?

 

[LakeFall]

Cat was glowing orange most of the time. Stove is in a room with 1.5 story ceilings and open balcony to the upstairs which makes heating the upstairs very efficient (almost gets too hot up there). Tstat is located in hallway behind chimney and heat does not circulate well to that part of the house. Ducting runs through attic and unfinished basement. That particular day I was burning 3year seasoned pine. However, I think I found my problem and its with LP gas burn which I have no way of measuring yet. (Tuesday vs Wednesday AUX heat which is LP) I need to re-run this study on warmer days when LP wont be used.

 

[EbS-P]

you should measure the air temps at the return and at a few registers to see how long it takes to get room temp air throughout the house once the blower comes on. Ducts in unconditioned spaces generally mean running the fan is net heat loss.

I have my heatpump set to a minimum run time of 15 minutes and a 2 degree Stage 1 to stage 2 temp difference. I don’t use the fan by itself in the winter.

But if you have 1.5 story open space I could see how running it might help distribute heat even if it’s a net heat loss.

 

[EbS-P]

If you have LP runtime you can estimate btus per hour if you know how many btus the burner is.

 

[stoveliker]

Have a ceiling fan as heat will pool up there.
And don't run the HVAC. Many folks here end up concluding it makes things worse rather than better.

Best to have a fan running low on the ground at strategic places to move cold air slow and steady into the stove room without mixing it with the warmer air higher up. It'll result in warm air flowing along the ceiling to where the cold air was taken from.

 

[LakeFall]

Have a ceiling fan as heat will pool up there.
And don't run the HVAC. Many folks here end up concluding it makes things worse rather than better.

Best to have a fan running low on the ground at strategic places to move cold air slow and steady into the stove room without mixing it with the warmer air higher up. It'll result in warm air flowing along the ceiling to where the cold air was taken from.

I wonder if i could achieve that by closing off the HVAC trunk damper and put one of these vent fans in the stove room? Theoretically it would pull from the floor vents in the cold rooms and with the damper shut completely, it wont pull from returns or upstairs vents. Has anyone tried that before?

 

[stoveliker]

I like the idea, if all of the ducts through which the air then flows are located within the insulation envelope.
That's the crucial part.

I don't know whether the trunk damper is very air tight though.

Another way is a through-the-wall fan. Fits between studs. Mount it near where you have an outlet (so you have can hardwire the fan and not have wiring visible), and suck cold air from the floor of that room and deposit it into the stove room.
Have the door of the "cold" room open, and it'll be replaced by warmer air.

 

[EbS-P]

I wonder if i could achieve that by closing off the HVAC trunk damper and put one of these vent fans in the stove room? Theoretically it would pull from the floor vents in the cold rooms and with the damper shut completely, it wont pull from returns or upstairs vents. Has anyone tried that before?
View attachment 335752

This just popped into my head. The results probably won’t impress. Think more along the lines of helping convective loops that may already exist. Or getting the coldest air out of where it is so it can be replaced by warm air.

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[crstrode]

I have an energy monitoring system and wanted to see how much energy I save burning wood. I picked 2 cold days this week with similar daytime temperatures. I have a LP furnace that kicks on under about 20deg or so therefore I only ran 12 hours during the day as I have no way to measure LP consumption. For those 12 hours I kept he insert well fed and at max air intake and fan speed. Active Zone temp needle was pointing straight up. I was surprised to see it only saved $0.50. Any input (other than maybe a larger sample size of days) on what I'm doing wrong here? I have a BK Ashford 25 and for wood burning days, I have a circulate mode on the AH that allows for a min amount of time the AH will run every hour, in this case 30 minutes. House is approx 2300 sq ft.

Date	21-Jan	22-Jan
Wood heat?	12 hours of wood burn	No
Daytime High/Low	28/19	30/21
Heat Pump kWh	17.923	21.019
Air Handler kWh	7.288	9.813
Est. stove fan 60W@12hrs (kWh)	0.72	N/A
Total kWh	25.931	30.832
Cost per kWh	$0.11	$0.11
Cost per day
Savings

[td]
$2.85

[/td][td]
$3.39

[/td]
[td]
$0.54

[/td]​

Comparing apples to oranges is very difficult. It is impossibly difficult with road apples and osage oranges.

 

[EbS-P]

I have some data to share. Similar climate to the op but warmer. We were gone dec 27- jan2. I looked and no HVAC or hot water usage the house uses 15kwh a day.

Yesterday the house used 50 kWh while we were all gone house was set to 65F. So that is 35 kWh on a cold day. Let’s call that $5. So a really cold day and keeping the house warmer maybe $7.

When I did my estimate I used $200 a year savings. I never expected to break even. And I burn anyway.

 

[30WCF]

Let’s not forget the chain saws, mixed gas, splitter, hauling wood…
I’ve never had to go get my own propane out of the ground, but I do cut my own wood.🤣

 

[stoveliker]

I have some data to share. Similar climate to the op but warmer. We were gone dec 27- jan2. I looked and no HVAC or hot water usage the house uses 15kwh a day.

Yesterday the house used 50 kWh while we were all gone house was set to 65F. So that is 35 kWh on a cold day. Let’s call that $5. So a really cold day and keeping the house warmer maybe $7.

When I did my estimate I used $200 a year savings. I never expected to break even. And I burn anyway.

What is that 15 kWh spent on?
. If you're not home - no laundry, no coffee, basically no resistive heat, and no HVAC, no tv, what takes 15 kWh?

My home uses a fridge and 3 LED lights for a few hours on a timer when I'm gone and HVAC is off.
TV and radio etc. are off (dead off, no ghost draw), computers are off,
Fridge and microwave clock...

 

[EbS-P]

What is that 15 kWh spent on?
. If you're not home - no laundry, no coffee, basically no resistive heat, and no HVAC, no tv, what takes 15 kWh?

My home uses a fridge and 3 LED lights for a few hours on a timer when I'm gone and HVAC is off.
TV and radio etc. are off (dead off, no ghost draw), computers are off,
Fridge and microwave clock...

Oh I forgot to turn off the bathroom floor heat. Two fridges one is 16 years old and lights dim when it starts. Internet. All my smart home devices. At some point I’ll control and drop the phantom loads and replace that fridge. Not this week

 

[EbS-P]

What is that 15 kWh spent on?
. If you're not home - no laundry, no coffee, basically no resistive heat, and no HVAC, no tv, what takes 15 kWh?

My home uses a fridge and 3 LED lights for a few hours on a timer when I'm gone and HVAC is off.
TV and radio etc. are off (dead off, no ghost draw), computers are off,
Fridge and microwave clock...

Floor heat runs 5-6 kWh a day.

 

[GrumpyDad]

It was zero to negative out last weekend.
My Dauntless in a 670 sqft expansion, w/ cathedral ceilings and 14 windows (yes 14), kept that room at 72-73 degrees, and the adjacent room at mid 60's. The adjacent room is very poorly insulated 2x4 walls with insulation batts from the 50's and 1/4 paneling. There is nothing but a crawlspace next to it. There is another couple of expansion that were much colder without baseboard heat. I didnt turn on the oil furnace once, except when I made the mistake of dialing down the stove at night too much on day and woke up to the stove room being 63 and the living room (adjacent room) at 46!

 

[NickW]

$.11 kwh!?!? That's right around what my off peak costs! On peak is 2 1/2 times that! If I did straight rate it's around $.17 I think.

 

[BillBurns]

I save a lot burning wood. My wallet is the only proof I need. Thats not counting the heating oil bill. I save basically 1500 every mild winter. A bad year, i still save 1000. Electric is down too, due to the steady warmth of the fire.

 

[Orion 4343]

Burning firewood is also not just about finances. Processing firewood keeps me fit, healthy, and sane. Hard to put a price on that, but I know I am coming out ahead.

 

[GrumpyDad]

Burning firewood is also not just about finances. Processing firewood keeps me fit, healthy, and sane. Hard to put a price on that, but I know I am coming out ahead.

I struggled with my stove early on, but with the damper closed It's a pleasure to generate heat from an arm full of logs for a big chunk of the day. Hard to put words to it. At first I tried to quantify my cost of the stove, plus splitter, plus time and effort to have wood delivered or to process what I get here and there for free from my property or elsewhere.
If you just try to match dollar for dollar against burning say oil or dare I say natural gas if you have it available, you will probably at best break even.
But go get a quote for a new furnace plus install.
Also consider that wood heat provides an emergency backup both short term and long term. All you need is some wood piled up in the yard for a few years

 

[reaperman1]

I think your over stating the wattage of the inserts fan. I have a BK double wheel fan on my Boxer which is probably the same as your insert. My fan runs around 29 watts as I keep it on the lowest setting. I have my fan connected to a smart plug that I can voice activate thru Alexa/google. That smart plug tracks wattage, Kwh, etc. for the past 30 days. Either way, the energy expense used by a blower fan is next to nothing. My fan used 5.26 Kwh in 201running hours. I pay 13 cents per Kwh, or 68 cents for the past 30 days or running my fan for 201 hours.