Degree days, Energy use

crash2009

The numbers are in, and the charts are compiled.  If I am reading the degree day data correctly, we had a colder winter and paid less for heating.  These numbers are a result of a considerable amount of work to our one-pipe steam system.  Last summer, I had the boiler re-piped, then insulated the mains and all the pipes in the boiler room, weatherstripped a couple doors, closed a few windows, threw away a few electric heaters, and installed a few radiator vents.  Then we upgraded the gas line, which gave us some steam pressure, which revealed some steam leaks.  The increased pressure nescesitated a vaporstat and the thermostat anticipator was adjusted.  The collapse of the 3rd floor stairs revealed the source of the overheating area of the house. 

Is it just this simple to compare the degree day data to the comparative fuel use of the same period?  Or do I need to dig deeper to arrive at a conclusion?



Total Nov, Dec, Jan, Feb 2010 = $3473

Total Nov, Dec, Jan, Feb 2011 = $2748

                        Savings of          $725



Wow thats huge!  I guess the more work you have to do the more significant the savings.  I should add a bit for this winter being colder than last.  Thanks for the books and the website Dan.  And a big Thankyou to all the members that helped.

BobC

Well done!

That's great news! I'm glad all your hard work paid off.



I'm still trudging down that same road. the steam system is reasonably happy and now I have to figure how to properly insulate an old new england cape (front and rear dormers) that has walls that are almost impossible to reach and insulate.



Bob

crash2009

Thanks Bob

I was only projecting a 7.5% saving, looks like I ended up with 20%.  I am pleased with the results.

When I was a kid, up in Saskatchewan, I worked for an insulation company.  The company sold cellulose fibre.  R-3.74 per inch.  I installed the stuff for awhile, then sold for them for many years.  We did some houses from the outside, and others from the inside.  We preferred to work from the outside because there was no mess to clean up, but ocassionally an interior wall would blow off making a big mess.  In houses that were in need of an interior paint job, we blew the walls from the inside, but it was kinda dusty.  We used a big two handed drill with a 1" bit.  There was an attachment for the insulation hose, to stick in the wall. 

JPF has been doing his one room at a time and he has it down to a science.  You may want to check out his insulation posts. 

Mark N

Usage

Crash maybe you should show your usage for gas in therms and electric in kwhs. In 2010 I spent less on gas than in 2009 but used more gas in 2010. My price per therm has dropped by about $.50 over the las few years. My price for electric hasn't changed.

crash2009

Yes

 therms and kwhs would be more accurate.  I am new to spreadsheets, and am working on displaying that data.  Do you have an example that I could copy?

Mark N

Can't Help

Crash I can't help with that. I keep track of mine on paper. I started keeping track after my new gas boiler was installed in December 2008. Before that I used oil and really had no way to track consumption.

crash2009

Are you

 the Mark that suggested to clock the meter?

Mark N

Yes

Yes that was me. You could just use the numbers on utility bills for that time period and figure it out on paper

crash2009

I thought that was you

I just wanted to thank-you personally.  The clocking was a pretty big thing here.  Others had suggested it, but I didn't get the message.  You succeeded in convincing me that it needed to be done.  The old gas line was a huge barrier preventing me from progress. 

I have to go to the DTE website and download the file again.  All my paper gets sealed into months and years.  Accountants, its a love-hate relationship.

    

haaljo

A good degree day data site is

http://www.degreedays.net/

You haven't adjusted for degree days from what I can tell and this year (in Boston at least) ~20% colder thru February. I wonder what measures provided the biggest reduction. The collapse of your stairs didn't sound good. I never thought a steam leak could cause that much damage. M'ust have been a doozy.

Dollars saved has to be adjusted for the crash in natural gas prices. If you were burning oil you'd be just about even dollar wise due to the high cost of liquid fossil fuels.

haaljo

A good degree day data site is

http://www.degreedays.net/

You haven't adjusted for degree days from what I can tell and this year (in Boston at least) ~20% colder thru February. I wonder what measures provided the biggest reduction. The collapse of your stairs didn't sound good. I never thought a steam leak could cause that much damage. M'ust have been a doozy.

Dollars saved has to be adjusted for the crash in natural gas prices. If you were burning oil you'd be just about even dollar wise due to the high cost of liquid fossil fuels.

haaljo

A good degree day data site is

http://www.degreedays.net/

You haven't adjusted for degree days from what I can tell and this year (in Boston at least) ~20% colder thru February. I wonder what measures provided the biggest reduction. The collapse of your stairs didn't sound good. I never thought a steam leak could cause that much damage. M'ust have been a doozy.

Dollars saved has to be adjusted for the crash in natural gas prices. If you were burning oil you'd be just about even dollar wise due to the high cost of liquid fossil fuels.

haaljo

A good degree day data site is

http://www.degreedays.net/

You haven't adjusted for degree days from what I can tell and this year (in Boston at least) ~20% colder thru February. I wonder what measures provided the biggest reduction. The collapse of your stairs didn't sound good. I never thought a steam leak could cause that much damage. M'ust have been a doozy.

Dollars saved has to be adjusted for the crash in natural gas prices. If you were burning oil you'd be just about even dollar wise due to the high cost of liquid fossil fuels.

crash2009

I don't know how

 to adjust for degree days.  I didn't know natural gas went down.



The re-pipe must have helped some.  Insulating the mains and all the pipes in the boiler room (I think) helped a lot.  Most of the savings, if you look at the red lines in the graph, were on electricity (electric space heaters were not needed this year).  The stairs fell apart because of a leak in the 3rd floor shower, not a steam leak.

Mark N

Your Welcome

Glad I could be of some help.

arches

Charting energy use

Here's how I chart energy use.

1. Define a consumption period. I assume yours is a monthly gas bill. Our building is oil-fired, so the periods vary (we get oil delivered every couple weeks at the height of the winter, every 6 weeks or so in the late fall/early spring heating months). Divide by the number of days in the period to get average daily consumption.

2. Determine the average temperature for that consumption period. I use the custom history tool at Weather Underground. See here for example:

http://www.wunderground.com/history/airport/KNYC/2011/3/1/CustomHistory.html?dayend=21&monthend=3&yearend=2011&req_city=NA&req_state=NA&req_statename=NA

3. Use an XY scatter plot in excel (or google spreadsheet, or otherwise) to plot average temperature on the horizontal X axis and fuel useage (NOT price) on the vertical Y axis.  Once the points appear on the graph, left click on a data point, and then right click and select "Add Trendline" to draw a best-fit line.

4. If you've made a change to your system, group the "before" and "after" data into different series to show usage.

On the sample graph I've included the older data is before any modifications were made, and the newer data reflects the most recent season with the cumulative effect of two years worth of various pipe and building (roof) insulation projects, venting, vaporstat installation, etc. I'm a little skeptical about the very low consumption during our coldest recorded period (hard to imagine how we could have used LESS oil at 28 degrees than at 33 degrees), but if you have a metered gas system it should be easier to get reliable usage data.

crash2009

Arches

So the black line is before changes?  What do the clusters of black diamonds represent?

And the orange line is after?  What do the orange triangles represent?

Can you e-mail me a copy of the file?  kendillen@sbcglobal.net  so I can see how the data is entered.

arches

data points

Yes, the dark blue line is "before" improvements, the orange line is after.

Each of the triangles represents performance in a heating period. Just for example, if we burned an average of 80 gallons/day during a period where the average outdoor temp was 31 degrees, a triangle would appear at the intersection of 80 on the Y axis and 31 on the X axis.

The line you see is the "best fit" trendline drawn through all the actual data points.

I'll send you the file.