MOD-CON... 18 Months Gas Usage Compared to Neighbors

Good stuff!
What type of emitters do you have?

That's great Rob. Usage after 6-26-16 looks quite different.

That’s a broad umbrella. Since you don’t know the usage patterns, appliances on grid, dwelling size, envelope construction, type of heat, number of occupants, or setpoint, setbacks of your neighbors.

i got one for you guys. We also got those usage charts from out local gas company for the first time ever a few weeks ago. I think I tossed it, but my usage was higher than most of my neighbors for the last twelve months.

I think I can explain, we've expanded the house three times over the years (was roughly 1400 sqft cape, now roughly double that. Our family of four grows to six or seven when the boyfriends/girlfriends and mother come every weekend and/or holidays. The house was under construction (no insulation in addition for approximately three months of the heating season).

What I'm getting at is i suspect NY Rob's information and data are real world. His neighbors maybe or maybe not. Mine should get better starting next weekend when I finally finish the new heating and dhw system. Someday when it's just my wife and I, all of the utility cost will likely drop significantly.

There are so many variable involved in this, that it is impossible to come to a definitive conclusion. The only thing is a comparison of the Therms uses monthly with the old system as compared to the new system. But...be aware last winter isn't the same as this winter so your need for nat gas can be different.

So does the term "all neighbors" include the "efficient neighbors"
in that average or just the neighbors with "non-efficient" systems for that typical house.
What size of house are we looking at and what is your average total HDD?

It seems the proper way to compare is to use HDD numbers and square feet/therm.
My state has a web site with HDD and CDD updated by the middle of each month.

I have a mod con doing 2300 sq feet on the first floor with 1700 basement. This is an average of 72 degrees. There is 1000 feet of attached unheated garage that might drop to 40-50.

We have average of 7151 HDD.
Dec 2017 was 1241 HDD......used 93 therms.
Jan 2018 used 135 therms for a 33 day cycle. (No HDD yet).
Highest most recent was Dec 2013 using 152 therms for 1451 HDD. That 2013-2014 season was 7611 total HDD.
We use an average of 25 monthly for DHW and NG cooktop.
IIRC the max SWT is 125 degrees.
Built in 1995 with time consuming painstaking air infiltration prevention measures. More so than R-values.
Passive solar that looks like a normal house.
To complicated to figure out ROI. But very comfortable.
It turned into a crusade/hobby of sorts.
When we moved here from a house 1/3 this size our utility bills stayed the same.
We go to our kids houses that have heat pumps and find it uncomfortable and noisy.

I am curious to hear from someone with a new house to compare therms/square footage/HDD.
Do you count a heated basement in with the total area?

NY_Rob, nice work! I think the way I interpret this data is that you reduced your usage by what appears to be a solid 25%, assuming the average neighbors didn't change their habits too much. Moving from average to just outside the top 20% with an older house is impressive. That's the difference between making the playoffs and watching the playoffs from home.

This is an interesting data point on real world vs. AFUE ratings and whether a cast iron boiler's AFUE should be compared directly to a mod-con's AFUE. I assume your old cast iron boiler had an AFUE of ~80%. Since your savings are ~25% when a 95% AFUE rated boiler replaces the old one, this data suggests that the 80% AFUE rating was unrealistically high and this measure doesn't seem to reflect as-installed reality consistently for cast-iron boilers, due to some combination of oversizing, performance degradation, etc.

That comparison software has recently been put into use (and mailings sent out) by utilities across the country. Having installed 'smart meters,' they decided to show off their data.

The only thing these graphs really convey is how much energy (gas, electric) one consumes compared to others nearby. There's no way for the utility to determine real efficiency. 'Single family homes' can cover a wide range of sizes, construction/insulation details, even types of heating systems, irrespective of how many people occupy them.

The lines on those graphs ought be labeled "you," "average consumption" and "low consumption."

I don’t disagree more benefit comes from the TDR, ODR, and a control strategy some mod/cons offer to make it play nice with the system, than the condensing. However condensing adds some more efficiency. Depending on “return water temperature” not combustion air temp. I can not comment on combustion air temperature. What happens when it’s -30?

WOW! Super job, Gordy. I'm going to save all those graphs.

I'm still wondering about the temperature of the combustion air. It surely must impact condensation and efficiency. Some those BTU's are going to raise the temperature of the combustion air. Also, I am wondering what was the temperature of the combustion air for those graphs.

"What happens when it’s -30?" Ya! That what I want to know.

Thanks for all the work.

so I'm curious... Does the price of NG change with usage or does everyone in the area pay the same price? In the case of LP most pricing is based on usage... use more-pay less...

lchmb said:

so I'm curious... Does the price of NG change with usage or does everyone in the area pay the same price? In the case of LP most pricing is based on usage... use more-pay less...

Our NG is provided by a cooperative. Price per ccf can vary month to month depending on the market. All residential customers pay the same rate regardless of usage. Not sure about businesses. Because it's a cooperative we don't have the option to shop around for competitive rates.
Prices have varied between 1.11 and 1.20 per ccf in the last two years.

NY_Rob said:

What is amazing to me is the fact that 8K BTU's can heat your house, even at freezing outdoor temps. 8K BTU's is the output of one of our stove top burners we use to make a pot of tea!

Non-heating system inputs are important considerations when temps are mild and houses are well insulated. Just about all electrical usage inside the house turns into heat energy, and people put out about 300-400 BTUs/hr. If a family of 4 is home and they are using 2 kW/hr in electricity, that's a net heat input of at least 5,000 BTUs per hour into the house.