energy usage this winter .. (it is over now right??)

jpf321

as some of you might recall .. this winter, I did things a bit differently .. I ran my heat-pumps during non-peak electric hours and my boiler during peak. as well, I had eTRVs installed on all rads and only heated the radiators that were below settemp. All temps were set at 70dF both years.



I started record keeping this season around 10/22/2010 .. as of today, below is my oil consumption usage.



OIL: 10/22/2011 - 3/26/2012

USED: 469.557 gals @ ~$3.50/gal

HDD: 3134.7 (degreedays.net 65F daily, KLGA)

GAL/HDD: 0.149

COST: $1645



Electric: 10/21/2011 - 2/25/2012 (they read MARCH today I will update upon receipt of bill)

kWh: 5015

Cost: $829.17 ($0.16/kWhr)



COST OF eTRVs: $1200

TOTAL COST 2011/12: $3675



Previous year 11/1/2010-4/1/2011

USED: 1000 gals @ ~$3.35/gal

HDD: 3972 (degreedays.net 65F daily, KLGA)

GAL/HDD: 0.252

COST: $3350



Electric: 10/21/2010 - 3/25/2011

kWh: 3527

Cost: $754.96 ($0.21/kWhr)



TOTAL COST 2010/11: $4104



SAVINGS by running eTRVS + Heat Pumps: $429

And the wife-comfort-meter this year was no different than last.



So my eTRVs paid for themselves ($1200) and I saved about $200 (assuming March electric is about $200). The cost of oil went up but my consumption dropped by ~40% (gal/hdd). Electric cost me only about $100 more than I would have spent had I not run the pumps. Yes the winter was much more mild (3972 HDD (2010/11) vs. 3135 HDD (2011/12)) .. but I still feel that I did pretty well with the way I ran things. Next year, there won't be the $1200 investment in eTRVs.



I hope this is interesting to someone. I'd love to get other people to share their stories of consumption this year.



jpf

Mark N

Usage

10/13/11 to 3/15/12 - 512.15 therms @$1.06/therm

10/12/10 to 3/16/11 - 642.60 therms @ $1.17/therm



The house was kept at 70 degrees no set back. I used a 130.45 less therms over the same period. I don't keep track of HDD data for my area. I don't use electric for heat.

jpf321

Check out http://Degreedays.Net

Check out http://Degreedays.Net

Or tell us your closest "weather representative" airport?

ChrisJ

how big

Are the spaces you are heating?



it looks like, for example January I had 786 HDD and used 228 therms for an average cost of $8.82 a day.  Of course this includes gas for cloths dryer, water heater and stove.  I'm heating 1700sqft @ 69F. Whats strange is my gas company said I had 786HDD but the website you posted claims I had 999 HDDs in January. Hmmm.



I'm fairly certain having close to zero insulation and almost all 110 year old windows and a lot of them is hurting me pretty bad.  I can't wait to see what happens next year when its actaully cold out. 

Mark N

HDD

According to the weather station closest to my house this is what I came up with.

10/13/11 to 3/15/12 - 3819 hdd's = .134 therms/hdd

10/12/10 to 3/16/11 - 4663 hdd's = .137 therms/hdd

jpf321

size and stuffing

my house is about 2400sq ft. double course brick built in 1920's. ThermoKing storms on single pane double hungs.



some rooms were blown with cellulose last year. nothing was done this year. the beauty of the eTRV system is I can now see immediately which radiators are almost constantly getting cold fast .. and now I can target more insulation in those areas.



My kids' bathroom which has 2 cold walls is a repeat offender. My mother-in-law's room on 3rd floor (not brick walls (rather wood and stucco) and against unconditioned space on ceiling and side walls) is is also cooling more quickly than others.



There are some rooms that I have rarely ever caught in active "heating" mode and seem to be very well tempered.



jpf

Mark N

Usage

JPF, I reread your post from last night and had a few thoughts. Last year you didn't run heat pumps to supplement your steam, so last years electric shouldn't be considered. For this year you have to figure out how much of your electric usage was for the heat pumps and use that in your calculations. Also you use your boiler to make hot water.

jpf321

i didn't

want people to think that "oh you used much less oil .. but your electricity must be through the roof" .. that is why I added last year's electric in there, to show that it wasn't through the roof. I was providing last year as a baseline .. anything more than baseline should be loosely considered heat pump excess.



yes, I do also make my DHW via boiler tankless coil .. but I did last year as well. so it should be a wash.

Mark N

Mild Winter

Understood. My usage was down a little over 20%, but my usage per hdd was nearly the same. Your oil consumption might have dropped 20 to 25 % just because of the milder weather. Maybe attribute the rest to using the heat pumps and the eTRV's.

jpf321

But isn't that the point of

Hdd? To normalize different years and/or locations.. As you mentioned, the per hdd was nearly the same. Wouldn't one expect mine to be had I not run the hp's and etrvs? I went from 0.252 to 0.147 that's fairly significant i think.

Mark N

For Discussion Only

Let say you didn't use the heat pumps and the eTRV's this past year and your oil usage dropped 20% because of the milder weather. By my math that would equate to .255 gal/hdd, 800/3134.7. Basically the same as last year. So using the heat pumps and eTRV's reduced your usage by 330 gallons.

jpf321

Understood...

I'll take it :-)

thanks for clarifying. Makes sense.

Maine Vent

Consumption

New boiler 11-4-11

Natural gas

Multiple skims

Still need some tweeking, new more BTU's, that will happen soon

Mild winter



November therms 34.6

December therms 170.5, boiler down for 1 week lost gas train valve

January therms 189.5

February therms 278.1

March therms not read this month



Total 672.7,,,,, plus at least 100 for March????

1840 Double brick Italianate



HDD for my area were 3727 for 11-1, 2-1



I don't have a clue how to correlated HDD to Therms for a practicable number????



Also I saved about 1800 gallons of fresh Maine water, from feeding my holey Burnham.



We are now very happy with boiler/gas set up. Thanks to everyone for all the tips and advise over the last 4 years.



Now I need to get some new windows upstairs, get some insulation into the walls, and tighten the place up.

Mark N

Outdoor Reset

What outdoor reset are you using? The Teckmar and Heat Timer are quite expensive.

Mark N

Outdoor Reset

Thanks, I'll have to check it out when you post it. Since switching from oil to gas a little over 3 years ago, the combination of better efficiency and dropping gas prices my home heating costs are a non event. The idea of the outdoor reset intrigues me but wouldn't be worth the effort.