Cost–benefit analysis

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libirm

Member
Jun 1, 2008
138
Long Island, NY
I check my usage with oil from last year and have saved only 50 gals to date.
Now that pretty disappointing considering the cost of the new stove & pellets.
Both furnace & water have been serviced, and maybe because it has been so warm the savings from stove is not as great as expected.
So here are a few questions.
Has any one found a site or knows what a Oil fired hot air furnace should burn per month or day?
Same question for a 50 gal. Bock oil fired hot water heater? Hot water usage is for Washer cloths/dish, showers.
I burn 1.5-2 gallons of oil per day roughly to heat water and a small apartment, my thermostat have not been set above 50 degrees.
Just trying to nail down some specs to see if I am on target with oil usage or what.
(Also trying to justify cost to my accountant -AKA Wife)
As always-thanks in advance! :)
 
Too many variables to give a single number. Generally oil burners are measured in gallons per hour, but it all depends on how often and long they run.

EDIT: although you can estimate the oil water heater from specs and generally available estimates of hot water usage (and also from the energy efficiency label on the heater, if there is one).

How many gallons of oil have you used in total this season, and how much in pellets?

And when you say "to heat a small apartment," is that heat controlled by a tenant?
 
libirm said:
I check my usage with oil from last year and have saved only 50 gals to date.
Now that pretty disappointing considering the cost of the new stove & pellets.
Both furnace & water have been serviced, and maybe because it has been so warm the savings from stove is not as great as expected.
So here are a few questions.
Has any one found a site or knows what a Oil fired hot air furnace should burn per month or day?
Same question for a 50 gal. Bock oil fired hot water heater? Hot water usage is for Washer cloths/dish, showers.
I burn 1.5-2 gallons of oil per day roughly to heat water and a small apartment, my thermostat have not been set above 50 degrees.
Just trying to nail down some specs to see if I am on target with oil usage or what.
(Also trying to justify cost to my accountant -AKA Wife)
As always-thanks in advance! :)

Because you generally take showers at approximately the same temperature range in mild and cold winters, the savings will not be as pronounced during a mild winter. You use hot water at probably about the same rate in both scenarios. So, yes as it is a mild winter you will not see as big of a difference.
 
My cost benefit calc went like this:

150 gal/mo Nov09 - Apr10
60 gal/mo Nov10 - Apr11 (based on last 4 fills)
Oil Savings of approx. 630 gal priced @ $3.30/gal = $2,080
Pellets bought $900
Net Savings in year 1 of approx. $1,180, and if I calc the cost of oil at market prices this winter rather than the price I locked in last July WOW!
Not to mention the house is warmer and the wife is happier, Priceless!!
 
Weird tolkienish figure said:
libirm said:
I check my usage with oil from last year and have saved only 50 gals to date.
Now that pretty disappointing considering the cost of the new stove & pellets.
Both furnace & water have been serviced, and maybe because it has been so warm the savings from stove is not as great as expected.
So here are a few questions.
Has any one found a site or knows what a Oil fired hot air furnace should burn per month or day?
Same question for a 50 gal. Bock oil fired hot water heater? Hot water usage is for Washer cloths/dish, showers.
I burn 1.5-2 gallons of oil per day roughly to heat water and a small apartment, my thermostat have not been set above 50 degrees.
Just trying to nail down some specs to see if I am on target with oil usage or what.
(Also trying to justify cost to my accountant -AKA Wife)
As always-thanks in advance! :)

Because you generally take showers at approximately the same temperature range in mild and cold winters, the savings will not be as pronounced during a mild winter. You use hot water at probably about the same rate in both scenarios. So, yes as it is a mild winter you will not see as big of a difference.

I'd agree with this but still...you must be seeing significant savings if your furnace has not even turned on for heat (I am in CT and while it's been mild...days in the 40's and nights around 30 would certainly kick on my oil furnace at 58 degrees several times per day (OK, all day every day because my house is drafty and old). The point being you must be saving on oil costs if that furnace has not turned on - and I can't imagine that your house got below 50 if you've been running your stove and feeling comfortable indoors...

It's more complicated because of the water but it's got to be many gallons less because of the heating system - no?

Mary
 
jdege said:
My cost benefit calc went like this:

150 gal/mo Nov09 - Apr10
60 gal/mo Nov10 - Apr11 (based on last 4 fills)
Oil Savings of approx. 630 gal priced @ $3.30/gal = $2,080
Pellets bought $900
Net Savings in year 1 of approx. $1,180, and if I calc the cost of oil at market prices this winter rather than the price I locked in last July WOW!
Not to mention the house is warmer and the wife is happier, Priceless!!

You use 150 gallons of oil per month basically for water? When I bought my house it had approx 225 gal of oil in it..got 150 gallons almost 6 months later. I keep my heat at 60 and use the wood stove all the time.

When I bought the house the guy told me he used 200 gallons last year for the WHOLE year. I also have a 2400 sq foot house with 4 people taking showers on a daily basis and trust me kids don't take short showers.
 
(I’d agree with this but still…you must be seeing significant savings if your furnace has not even turned on for heat (I am in CT and while it’s been mild…days in the 40’s and nights around 30 would certainly kick on my oil furnace at 58 degrees several times per day
(OK, all day every day because my house is drafty and old). The point being you must be saving on oil costs if that furnace has not turned on - and I can’t imagine that your house got below 50 if you’ve been running your stove and feeling comfortable indoors…)

That is what so troubling about this all....my oil provider says that I have used only 50 gallons less than last year 1/10 to 2-11 and from 1/11-2/12.

Last oil fill, 41 days in between 125 gals. @3.97 per gal.

That's about 3 gal a day.
My tenant is my sister so I know she pretty good with the thermostat, however I will remind her about turning it back, sadly my system will allow a set bacl thermostat...that's what my service guys tell me, it the way the system is set up.

Good point about the water heater, its weather irrelevant to temperature out side, it heats the water regardless.

I think if I had a leak it be more evident, and i am hoping that the guy delivering my oil is completely honest, reputation is good around here.
 
RORY12553 said:
jdege said:
My cost benefit calc went like this:

150 gal/mo Nov09 - Apr10
60 gal/mo Nov10 - Apr11 (based on last 4 fills)
Oil Savings of approx. 630 gal priced @ $3.30/gal = $2,080
Pellets bought $900
Net Savings in year 1 of approx. $1,180, and if I calc the cost of oil at market prices this winter rather than the price I locked in last July WOW!
Not to mention the house is warmer and the wife is happier, Priceless!!

You use 150 gallons of oil per month basically for water? When I bought my house it had approx 225 gal of oil in it..got 150 gallons almost 6 months later. I keep my heat at 60 and use the wood stove all the time.

When I bought the house the guy told me he used 200 gallons last year for the WHOLE year. I also have a 2400 sq foot house with 4 people taking showers on a daily basis and trust me kids don't take short showers.

No I used 150 gal/mo last year when I was heating the whole house on forced hot water. Since the stove I use 60gal/mo to heat the master bedroom an d hot water.
 
libirm said:
(I’d agree with this but still…you must be seeing significant savings if your furnace has not even turned on for heat (I am in CT and while it’s been mild…days in the 40’s and nights around 30 would certainly kick on my oil furnace at 58 degrees several times per day
(OK, all day every day because my house is drafty and old). The point being you must be saving on oil costs if that furnace has not turned on - and I can’t imagine that your house got below 50 if you’ve been running your stove and feeling comfortable indoors…)

That is what so troubling about this all....my oil provider says that I have used only 50 gallons less than last year 1/10 to 2-11 and from 1/11-2/12.

Last oil fill, 41 days in between 125 gals. @3.97 per gal.

That's about 3 gal a day.
My tenant is my sister so I know she pretty good with the thermostat, however I will remind her about turning it back, sadly my system will allow a set bacl thermostat...that's what my service guys tell me, it the way the system is set up.

Good point about the water heater, its weather irrelevant to temperature out side, it heats the water regardless.

I think if I had a leak it be more evident, and i am hoping that the guy delivering my oil is completely honest, reputation is good around here.

Get a gage on your oil tank that will show the amount you have in there. I DON'T TRUST ANYONE!
 
I have all electric. I went from $350-$500 electric bills/month to $90 electric bills. last year I burned a little under 4 tons. It feels like I'm spending less, and my house is much warmer.
 
Regarding Gauge-
I just put a piece of tape on the tank gauge, it is a scoash above 7/8 right now- I pretty sure it is a 275 gal tank, we see what the fill says-

One question I have not answered yet is to how pellets have I used? So far one ton, there have days when the stove has run but a few hours.
 
Something doesn't compute here - 1 ton of pellets should (very roughly) be 100 - 120 gallons of fuel oil. Obvious question: are you keeping it warmer than usual (especially, do you run the room with the pellet stove a lot hotter to keep the rest of the house warm)? And how is the forced hot air system set up? The "system doens't allow for a setback thermostat" sounds either odd, or might mean you have a single zone? IOW, if the apartment calls for heat, do you have hot air coming out of the registers?

BTW, I checked the specs on the Bock, and it looks like it's not very efficient. So that will account for some of the oil, but it's hard to say how much.
 
-
 
Thanks Krik-

I have multiple zones in house and the apartment is considered a "slave" zone. So it can't have a setback, at least that is what I have been told.

Yes there is a little bleeding of the hot air into al the vents, but In a effort to find out whats going on, I shut all my vents off in the main house. That will push any hot air into the apartment when it calls for heat.

Regarding the Bock, where did you find specks? I think I might call them to see if there is a more efficient burner, although I am sure it will cost $400.00 or more which will kill the cost - benefit ratio.
Thanks for the info!
 
Web site - but it doesn't list it for all models. Somewhere it says the 30 (32?) gal version is a max "EF" of 0.68. Check out http://www.aceee.org/consumer/water-heating for a discussion of efficiency. Note that it isn't just the burner, but also standby and flue losses that are included - just upgrading the burner might not help much. Even with electric models being more efficient I don't think it pays to go electric due to high cost of electricity. It looks like the EF isn't way out of line for this type of heater, so I wouldn't worry about it too much.

But either way, it doesn't make sense that if all else is the same you'd save only 50 gals of oil by using 1 ton pellets.
 
well I had my stove installed at the end of december bought 1 ton and also had an oil delivery i know its been a warm winter but i only used around an 8th of a tank of oil and 33 bags of pellets and the average temp of my house is around 74 degrees last year i kept the heat on 68 and went through 230 gallons of oil in the same time period i pay almost $4.00 a gallon for oil and so i am very happy with my stove I love it and it also looks great
 
200 gallons in 15 months. Two people, retired. Hot water and back up heat. This past early fall, I only put 100 gallons in. Looks like I still have over half of that. Last year we burned 6 tons, this year looks like it will be just. Under 5.
Oil company won't give a discount anymore because I don't have. Auto delivery. Next time I'm shopping around. I could have saved 30 cents a gallon.
 
I am all electric and have cut my killowatt usage in half. I'll realize more savings next year when my squatters are gone...

Free advice of the day: NEVER, EVER let anyone move in "temporarily" - especially if they are "family"...
 
Something is not right, i am on automatic delievry and my fill ups are about 50 gallons, when i didnt have a stove they were 200 gallons, i burn 24/7 and my oil heat rarely turns on. seems like you are not burning enough pellets and you are relying on your furnance. i would guess i am burning 1 bag a day while my boiler would burn 4 gallons a day. about same price $4 bag/gallon, besides i am running a lot warmer in my home
 
John97 said:
I am all electric and have cut my killowatt usage in half. I'll realize more savings next year when my squatters are gone...

Free advice of the day: NEVER, EVER let anyone move in "temporarily" - especially if they are "family"...

"Nothing more permanent than a temporary measure", in the case of Government.....Like income tax in Canada ;)
 
My savings,
1000 dollars for used stove and pipe
500 dollar electric bill, cold months
200 dollar electric bill now, still heat guest house with electric
200 month pellets, house 7 degrees warmer
easily paid for itself first year
 
Ejectr said:
What is the cost of one of these? I have an oil fired hot water heater I'd love to get rid of.

I've seen em for around $1,500 or so.

But remember, they don't magically make heat - they extract heat from the surrounding air to heat the water (it's like an air conditioner, dumping heat into the water). The colder it gets in the room w/ the heater, the less efficient it gets. So you need to heat that air (e.g., with pellets), which then should indeed come out ahead of full electric. However, for places where heating dominates cooling it's not as great a money saver as they make it out to be. Also, these things have moving parts - getting a well-insulated regular tank is a safer bet from a reliability perspective.
 
Krik said:
Ejectr said:
What is the cost of one of these? I have an oil fired hot water heater I'd love to get rid of.

I've seen em for around $1,500 or so.

But remember, they don't magically make heat - they extract heat from the surrounding air to heat the water (it's like an air conditioner, dumping heat into the water). The colder it gets in the room w/ the heater, the less efficient it gets. So you need to heat that air (e.g., with pellets), which then should indeed come out ahead of full electric. However, for places where heating dominates cooling it's not as great a money saver as they make it out to be. Also, these things have moving parts - getting a well-insulated regular tank is a safer bet from a reliability perspective.
Hmmm...that means replacing the one I have in the basement would be a bad idea in the summer when it is cool down there. It would be great during the heating season as that is where the pellet furnace is and really heats the basement in the winter. With the current price of oil at $3.86/gallon, I spend just over $1,000 for hot water a year.
 
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