Heat degree days...where are you, and what's your total for a burning season?

[saskwoodburner]

Hey guys, I was just looking back on the last few years of our weather on the Environment Canada website, and also from The Weather Network. I've never really paid attention to heat degree days, but I think I get the jist of it now.

So here's what we're looking at where I live.

http://legacyweb.theweathernetwork.com/statistics/degreedays/cl4056240/cask0251

It looks like an average of 5585 heat degree days total, starting October through April. Not sure if this is good or not, but that's the number I'm left with. I didn't include the other months, as it would be rare to run the wood stove through those months.

If you want to include the whole year, go ahead, but please post the October-April separately.

So, where are you from, and where does your total sit for an October-April measurement? There's guys from all over, should be interesting I think.

She's pretty chilly up here in Saskatchewan btw.

Mods: I had no idea where to post this thread? If I'm off base, please put it where it best belongs. Thanks.

 

[Squirrel]

South of Ottawa, Oct - April 4,140. Glad to be back in Ontario after 10 years in Swift Current where you had to drive 100 miles to find a tree.

 

[Diabel]

South of Ottawa, Oct - April 4,140. Glad to be back in Ontario after 10 years in Swift Current where you had to drive 100 miles to find a tree.

Thanks you Squirrel,
I was about to do the calc.
You beat me to it!

It has been one of the warmest Nov and early Dec in my memory here in Ottawa.

 

[saskwoodburner]

South of Ottawa, Oct - April 4,140. Glad to be back in Ontario after 10 years in Swift Current where you had to drive 100 miles to find a tree.

Yeah, but there was a hill. So, there's that.

 

[Poindexter]

Are these metric heating degree days? I would have thought a lot more than 5500 for as far north as you are.

In Farenheit, base 65dF, my trailing 30 year average is 12,285 HDD from Oct 1 to Apr 30. Haven't collected data for current season yet, it seems kinda mild.

 

[Squirrel]

Yep, these be the new-fangled metric ones.
Since a temperature difference of 1°C is equivalent to a temperature difference of 1.8°F, Fahrenheit-based degree days are 1.8 times bigger than their equivalent Celsius-based degree days.

 

[saskwoodburner]

Are these metric heating degree days? I would have thought a lot more than 5500 for as far north as you are.

In Farenheit, base 65dF, my trailing 30 year average is 12,285 HDD from Oct 1 to Apr 30. Haven't collected data for current season yet, it seems kinda mild.

Come to think of it, it was based off of Celsius. I'll see what it is in F.

10,053 HDD going with the Farenheit scale.

 

[huauqui]

We run about 6,000 HDD from October - April (add about 200 to include September and May if you want.) I am just south of Omaha NE.

 

[Ashful]

Yearly average of 5000F HDD's here, about 30 miles north of Philadelphia, on the usual 65F base temp.

More interesting would be knowing what folks average in BTU/HDD, particularly if you're able to subtract out your BTU/day utilization for DHW (not trivial).

 

[dh1989]

I turn the heat on Oct 15 and off May 1. The 3 yr average for degree days for that span is 5550 (base 65F).

I put an hour meter on my oil burner which burns 1 gal/hr. I also monitored the water meter and hot water use for a while last winter (I have a tankless coil on the boiler for hot water). I found that, adjusting for hot water use, I use .081 gal/HDD of oil for heating to keep upstairs at 65F and downstairs at 55F. At 5550 HDD and 138,500 BTU/gal with 80% boiler efficiency I have about 49,800,000 BTU per season. If I kept downstairs at 65F too it works out to .10 gal/HDD or 61,500,000 BTU per season.

I calculated my home heating index (HHI) which is BTU/HDD/sqft and came up with 7.9 (moderate to average). I have R38 fiberglass batts in the attic. I checked the ceiling with my thermal camera and I have a lot of air leaks and am missing all insulation around the edges as the rafter vent baffles were never installed. I'm going to be air sealing and adding insulation next weekend so will see how my BTU usage changes.

 

[Ashful]

I put an hour meter on my oil burner which burns 1 gal/hr.

How have you determined the burn rate of your oil burner? The number stamped on the tag is simply a maximum rating, and they are rarely configured to run at that rate.

I calculated my home heating index (HHI) which is BTU/HDD/sqft and came up with 7.9 (moderate to average).

Interesting. Never seen this figure. If I use the numbers I was running in 2012, I get 9.0 BTU/HDD/sq.ft. However, I have tightened things up a bunch, and added sq.ft., and have never gone back to re-figure our rate. I'll need to track usage this winter.

I see two things having a high impact on this number:
1. We typically waste more BTU's when heating via wood, than with a central system. Reason being that I'd have the t'stats set to go down to 62F during the work day and overnight, but I keep the joint heated 24/7 when burning wood. So, I've added about 80 hours per week to the time I keep the place above 70F.
2. Like most woodburners, I find myself keeping the house a lot warmer on wood, than I ever did with central heating. We used to warm various parts of the house up to 68F or 70F, before wood, but now find ourselves keeping the joint at or above 73F.

Since energy loss is proportional to the difference between indoor and outdoor temperature, multiplied by time, we're really consuming a lot more BTU's at the higher temperature and longer hours.

 

[dh1989]

How have you determined the burn rate of your oil burner? The number stamped on the tag is simply a maximum rating, and they are rarely configured to run at that rate.

If you know the nozzle size and pump pressure you can find gal/hr. I verified my usage when I topped the tank off in the spring and I believe I was within 3-4%.