NG furnace vs modern heat pump

[LMichaels]

Another thing that bugs me with all this "electrify" this and that, electric cars and so on. All this electricity comes from somewhere. Vast majority burning fuels far more polluting than the NG we burn in our homes. Or the very well controlled ones coming out of modern vehicle's tail pipes. Until IF or WHEN we can produce electricity without some ancillary pollution at the source. Electricity (any energy) doesn't come for free or without pollution. Maybe one day but we're a long way off from that day.
Another issue is the cost of whatever energy you use or have easily available. Here, (for reasons if I go into would get me banned for life), electricity rates are some of the highest in the country. It makes no economic sense to use it in IL. Let alone the cost of the equipment and so on. Yeah you can make your house look like a solar generation farm, adding 10s of thousands of $$$ of equipment like my son in law did. But even after all that, the way those things work he still cannot run his home directly off the solar panels.
There may be some cool and pretty good technology down the pipe but it's still a looooooong way to go

 

[JKalchik]

Agreement here also. Ductless splits don’t make a lot of sense if you have a ducted system. However, the ducted inverter systems we began the discussion on would absolutely be a good candidate for consideration as a replacement for the a/c side of things if someone is looking for additional efficiency.

If/when we replace the furnace, a complete HVAC replacement/upgrade would definitely be in the works. As it stands, NG furnace with a bog standard A/C system (which I rather obviously have NOT cleaned enough, but that's a beer story....)

 

[EricV.]

I am on a fixed-rate plan with my electric company, they reevaluate my plan ever January. My annual usage varies mainly on how extreme the summer & winter month's are. Overall my fixed rate continues to go up mainly due to Kilowatt hourly rate increases. My home is +2500 square feet & I just paid my new 2023 rate which is at $195/mo. up from $156 in 2022 & $144 in 2021.

 

[k walsh]

Tom
I'm here in Digby, Nova Scotia, Canada. We bought a house here 3 years ago after moving from Vancouver Island. The house had only electric baseboard heating. We moved in in February and our first 2 months electricity bills were ridiculous.

We installed a Pacific Energy wood stove. We're currently burning about 2-2.5 cords of hardwood a year at a cost of $300Can per cord.

Would we do better with a heat pump? We also have some severe storms that knock out our power. What does it take to run heatpumps on a generator?

Truly looking forward to your informed reply.
Ken in Nova Scotia

 

[TomRc]

Tom
I'm here in Digby, Nova Scotia, Canada. We bought a house here 3 years ago after moving from Vancouver Island. The house had only electric baseboard heating. We moved in in February and our first 2 months electricity bills were ridiculous.

We installed a Pacific Energy wood stove. We're currently burning about 2-2.5 cords of hardwood a year at a cost of $300Can per cord.

Would we do better with a heat pump? We also have some severe storms that knock out our power. What does it take to run heatpumps on a generator?

Truly looking forward to your informed reply.
Ken in Nova Scotia

Your design temperature looks to be very similar or even a bit lower than mine here in NY. Personally, it would be difficult to recommend any sort of heat pump system for your home. With it being only electric baseboard and assumed to be lacking any ductwork, you would likely be looking at multiple ductless split heads to heat the home evenly...figure 1 for each bedroom and 1 for each separated living or common area. And, of course, they would all need to be rated as max heat capable for effective heat operation to -15ºF. That is a significant investment in equipment, materials, and labor that only you can determine as worthwhile or not. I’ve seen too often where folks will try to eliminate a head here or there in the design to save some money but it always comes back negatively in the form of cold spots within the home. If you were to go this route, these units would be purring along and offering some efficiency savings most of the year but they will spin the meter on a design day or below much like electric baseboard would. As far as a generator goes, you’d be looking at a minimum 22kw standby generator to power all of them with some power left over for a few other critical loads during a power outage.

 

[Jay D in Jersey]

Replaced two furnaces in 2022 and one AC unit. Both NG...a Bryant furnace and AC unit in the beach house
, the one it replaced was 23 years old...furnace was OK, AC was shot...and a Payne furnace in our primary home...both single stage.
The Payne replaced a 2012 Carrier Infinity two stage and we got a decent chunk of credit from the Carrier warranty for the failed secondary heat exchanger. I think we paid $4500 for the Payne and it was installed perfectly with a new Ecobee thermostat. Think we paid $8800 for the replacement Bryant HVAC system at the beach. Use a kind of rudimentary Honeywell WiFi thermostat. Both systems work excellent.

 

[k walsh]

Tom, thank you so much for the information. This is so good to know. I only have a 4 kw generator for our power outages to run our fridge, water pump from our drilled well and deep freeze. With my chainsaw I can provide heat! Thanks for your professional information as we have been seeking opinions.
Cheers
Ken

 

[Brett-EDH]

Any Bosch IDS 2.0 owners? Thoughts, comments, concerns, feedback on your experiences?

 

[Timothy F. Lewis]

Can’t help on that Brett but my Bosch dishwasher is great!

 

[Brett-EDH]

Can’t help on that Brett but my Bosch dishwasher is great!

That’s great to hear especially all you went through to get it up and running. We use ours daily, sometimes twice daily on weekends. Makes us all very happy. Excellent build quality and does its job well.

 

[LMichaels]

That’s great to hear especially all you went through to get it up and running. We use ours daily, sometimes twice daily on weekends. Makes us all very happy. Excellent build quality and does its job well.

Yep, I put my first Bosch in back when we had 3 girls here. So dishes accumulated all day long and that thing pretty much ran twice a day for 10+ years. I had to do one repair on it (the detergent dispenser) and then after about 10 years a pump went bad, I replaced the pump and it worked for about 6 more months and another pump went out and I decided it had given me all it was going to give me and I replaced it

 

[DanHoo]

I'm wondering a conversion spreadsheet type calculator exists that shows heating output based on input cost with efficiency factors.

Electricity is billed in KWh
Gas is billed in Therms

A forced heat gas furnace needs GFe1 watts per hour to run the fan and GFt1 therms per hour with a burner running. With a rated efficiency GFP1 of the furnace and a loss ratio of DuctingP2 in ducting, all to provide some amount of heat.

Based on the net heat output and the heating needs, I guess one could determine how many hours per day this would run to raise home temp.

Does such a spreadsheet calculator already exist?

The cost model needs to factor in installation and maintenance costs
- purchase cost including installation, permits, tax credits, rebates etc.
- financing costs ( if financing is needed )
- annual maintenance cost ( planned preventative maintenance )
- likely repair cost ( Guestimate on repair costs in the Future )
- monthly electricity and or NG/propane gas costs.

The unknown variable is the electricity and gas cost.
Another is the heating / cooling demands by month.

And, if one has PV solar, will the solar generation cover the electricity costs, or perhaps in the case of a heat-pump, its shifting cost from NG to electricity, but using more electricity than the solar provides.

If anyone has something like this I'd be interested so I could run through some numbers.

edit: I started googling around for one and thought I'd post a couple of links

Found this one. Its a start for the monthly generation

Fuel Comparison Calculator

Compares cost and CO2 emisssions for various fuels

www.chinetco.com

Financing & Implementation

Make sense of the best financial tools to meet your energy goals and ensure your sustainable future. As a single-source partner, Trane can help you make sense of your financing and contracting options to determine the best way to achieve your infrastructure and carbon reduction initiatives.

www.trane.com

( there is a tool, but it is a broken link)

 

[TomRc]

I'm wondering a conversion spreadsheet type calculator exists that shows heating output based on input cost with efficiency factors.

Electricity is billed in KWh
Gas is billed in Therms

A forced heat gas furnace needs GFe1 watts per hour to run the fan and GFt1 therms per hour with a burner running. With a rated efficiency GFP1 of the furnace and a loss ratio of DuctingP2 in ducting, all to provide some amount of heat.

Based on the net heat output and the heating needs, I guess one could determine how many hours per day this would run to raise home temp.

Does such a spreadsheet calculator already exist?

The cost model needs to factor in installation and maintenance costs
- purchase cost including installation, permits, tax credits, rebates etc.
- financing costs ( if financing is needed )
- annual maintenance cost ( planned preventative maintenance )
- likely repair cost ( Guestimate on repair costs in the Future )
- monthly electricity and or NG/propane gas costs.

The unknown variable is the electricity and gas cost.
Another is the heating / cooling demands by month.

And, if one has PV solar, will the solar generation cover the electricity costs, or perhaps in the case of a heat-pump, its shifting cost from NG to electricity, but using more electricity than the solar provides.

If anyone has something like this I'd be interested so I could run through some numbers.

edit: I started googling around for one and thought I'd post a couple of links

Found this one. Its a start for the monthly generation

Fuel Comparison Calculator

Compares cost and CO2 emisssions for various fuels

www.chinetco.com

Financing & Implementation

Make sense of the best financial tools to meet your energy goals and ensure your sustainable future. As a single-source partner, Trane can help you make sense of your financing and contracting options to determine the best way to achieve your infrastructure and carbon reduction initiatives.

www.trane.com

( there is a tool, but it is a broken link)

Thanks for impromptu reminder, Dan. I was going to check back in with a link to something similar myself. The data is provided by the NYS Energy Research & Development Authority.

NYSERDA publishes current statewide and localized average costs for fuel oil, propane, natural gas, etc right on their website in a detailed and geographically specific format. I originally found these pages while trying to compare some energy costs for a customer who is considering a switch from oil to LP. With the information published there and some historical usage data from the customer, I was able to easily lay out a fairly concise and accurate comparison of these fuel sources for consideration in just a few steps.

Here’s the link to the propane page: https://www.nyserda.ny.gov/Researchers-and-Policymakers/Energy-Prices/Propane/Average-Propane-Prices

Other fuel sources can be accessed from tabs on the left column of the LP page.

And yes, it is all NY based of course, but you can substitute your own local fuel costs as you do the math for appropriate results.

 

[DanHoo]

Thanks for impromptu reminder, Dan.

Thanks for the link Tom. It wasn't really an impromptu reminder, but more of a To-Do that I need to do to get my head around the financial part of this.

I think the quality and reliability aspect may be more important to me, but I also need to run the numbers since that's how I roll.

 

[DanHoo]

I think there is a great amount of diversity in HVAC needs, costs etc.

For me and my house, cooling demand is much greater than heating demand, so investing there is more important, I think.

It would be fantastic if I could replace my 25 year old 5 ton SEER 8 York air conditioner with one that will last another 25 years and be equally reliable. SEER 14 is min in CA so it will be more efficient, yet it will be interesting to see the cost/benefit differences of 14 vs 16 vs higher SEER ratings.

My heating needs are much less and I have a 38K BTU high efficiency gas fireplace that heats the main room we spend time in so we can keep the rest of the house cooler. From a resale point of view I would still want to size the heat portion to not rely on this but the heating efficiency is much less important to me financially. Reliability however is a key factor for me.

 

[Brett-EDH]

Thanks for the link Tom. It wasn't really an impromptu reminder, but more of a To-Do that I need to do to get my head around the financial part of this.

I think the quality and reliability aspect may be more important to me, but I also need to run the numbers since that's how I roll.

what got me going deeper into this research:

my PGE bill, basically heating the home, hot water, cooktop, and clothes dryer, was $345 last month.

my neighbor, in a 300 sq ft smaller home than me, has a pool, installed Rheem heat pump multistage units (2 split systems like me), gas cooktop, gas water heater, unknown clothes dryer, had an electric bill of $110 for the same period. He also has a controllable pool pump to run it on low load to keep the pool clean.

my YOY NG therms used were:
Jan 18 2022 bill - 134 therms, temps were 46F / H63F / L 28F - $320.86 - 5 people
Jan 18 2023 bill - 122 therms, temps were 48F / H66F / L 28F - $345.65 - 4 people



my largest home heating is Dec and Jan and then by mid Feb (around now) my home heating comes to an end as we have southern sun hitting 30-40% of my home that we can get to 70F internal at day peak temp (yesterday for example).

so if I can save $200/ mo/ over two mos, $400 on heating costs AND get an AC that is substantially more efficient, which heat pumps are, i am projecting i can save $800-$1000 a year on heating and cooling.

SMUD is giving $3500 in rebates per replaced system, i have two (2) split systems so $7000 in rebates, and the Feds will give me up to $2000 in tax credit (30% of total new install and unit costs up to $2K max), that's $9k in value in year one off the top.

Now i'm waiting for my first contractor proposal to come in so i can see what this will cost me, after the $7000 rebate in actual net expense for total install (2 new high efficiency systems, multistage and some electrical work in the job bid). I have to guess i'll be at $17k my cost, hopefully less.

if i reach the $1k annual savings, my roi would be 17 years. BUT, and this is a big BUT, if we stay in the home for 10 more years and i go to sell the home, i am selling the home with a modern system that the next owner should be good with for at least 10 years (we're low on usage and my current systems are 21 years old this year and still chugging along). so the upgrade adds value to my home versus a home that's not upgraded or will cost more to own/operate and maintain a non inverter system.

i also estimate and project the cost to heat and cool with either NG or electric will increase so i have to presume the ROI window could be as soon as 10 years, but likely in the 12-15 year range.

i'm not looking at ROI solely. ROI is nice but one needs heating and cooling, regardless. if I have to make one major repair of either unit currently installed I could be looking at $500-$2k in expenses over the next 24 mos. and that, call it $2k for a system failure of some sort, doesn't get me a new system, but just repairs on a very old and inefficient system.

so say my real expense is $15k net after budgeting service and spending two more years of higher NG costs and elevated cooling costs (the $2k in projected savings.)

so if i move on this purchase/install for this season, i cut my exposure down by potentially $4k in the next 24 mos. So $17k could become $13k.

this math makes it more clear to me, how i see money/use/costs in projections for the coming 24 mos.

i'll post info on my bid when i receive it. and i will secure 2 additional bids as well. i'd rather get this done before the summer season starts here.

 

[TomRc]

I think there is a great amount of diversity in HVAC needs, costs etc.

For me and my house, cooling demand is much greater than heating demand, so investing there is more important, I think.

It would be fantastic if I could replace my 25 year old 5 ton SEER 8 York air conditioner with one that will last another 25 years and be equally reliable. SEER 14 is min in CA so it will be more efficient, yet it will be interesting to see the cost/benefit differences of 14 vs 16 vs higher SEER ratings.

My heating needs are much less and I have a 38K BTU high efficiency gas fireplace that heats the main room we spend time in so we can keep the rest of the house cooler. From a resale point of view I would still want to size the heat portion to not rely on this but the heating efficiency is much less important to me financially. Reliability however is a key factor for me.

Your needs are right in line with what Brett is thinking. He and I took things offline into an email exchange and roughed out a load calculation for his specific home in the process. Bosch makes the inverter ducted units in both 18 and 20 SEER options and either one would be capable of providing stand-alone heat and cooling efficiently for your climate.

 

[Brett-EDH]

I think there is a great amount of diversity in HVAC needs, costs etc.

For me and my house, cooling demand is much greater than heating demand, so investing there is more important, I think.

It would be fantastic if I could replace my 25 year old 5 ton SEER 8 York air conditioner with one that will last another 25 years and be equally reliable. SEER 14 is min in CA so it will be more efficient, yet it will be interesting to see the cost/benefit differences of 14 vs 16 vs higher SEER ratings.

My heating needs are much less and I have a 38K BTU high efficiency gas fireplace that heats the main room we spend time in so we can keep the rest of the house cooler. From a resale point of view I would still want to size the heat portion to not rely on this but the heating efficiency is much less important to me financially. Reliability however is a key factor for me.

note, it's not just about seer with heat pump/inverter technology. i've learned a lot in a week. youtube is your friend.

my first looksee are these units: https://www.bosch-thermotechnology....inverter-ducted-split-family-ids--18527266-p/

if you're running a single 5T unit, your purchase costs will be a few g's less than my two, smaller units (3T and either a 3T or 4T on the upstairs unit). current home systems are two 3T units.

the reason SEER isn't the whole game, it's how this technology works. dynamic range of 30%-130% in 1% increments on the fan speed. basically, the new technology sips electricity to maintain desired inside temp. old units just suck electrical load to dump cold air into your home and wash/rinse/repeat every time the AC is called to make cold air. massively inefficient.

 

[Brett-EDH]

Your needs are right in line with what Brett is thinking. He and I took things offline into an email exchange and roughed out a load calculation for his specific home in the process. Bosch makes the inverter ducted units in both 18 and 20 SEER options and either one would be capable of providing stand-alone heat and cooling efficiently for your climate.

we're a few short miles from each other. same microclimate.

of note, my hvac guy pegged summer design temp at 102F. i'm awaiting his proposal for interior set target temp to see how this all balances out.

 

[DanHoo]

we're a few short miles from each other. same microclimate.

Your needs are right in line with what Brett is thinking. He and I took things offline into an email exchange and roughed out a load calculation for his specific home in the process. Bosch makes the inverter ducted units in both 18 and 20 SEER options and either one would be capable of providing stand-alone heat and cooling efficiently for your climate.

Brett and I have the same climate however my electricity costs are 2x to 3x higher because we have have different utility companies for electricity. NG fuel costs are the same.

My rates are:
Winter Below Baseline: $0.31/kWh Peak $0.29/kWh Off-Peak
Winter Above baseline $0.39/kWh Peak $0.37/kWh Off-Peak
Summer $0.39/kWh Peak $0.35/kWh Off-Peak

Brett's rates are
Winter $0.112/kWh Peak $0.154/kWh Off-Peak
Summer $0.135 Midnight to noon | $0.1864 noon to 5pm | $0.3279 kWh 5pm to 8pm |$0.1864 8pm to midnight

For me, adding electrical load in winter will have less of a cost savings. My winter electricity use is within the lower priced baseline, however if I went with electric heat I would likely exceed baseline and be in the 37 to 39 cent per kWh range.

Also, I have an 8KW Solar PV system nearly perfectly sized for the current net equivalent metering program. I an annual electrical true-up bill and last year it was just over $100. If the AC is much more efficient then I'll owe less, but once it goes below zero, PGE pays almost nothing for excess generation.

For NG, I have the gas fireplace, furnace, hot water heater, clothes dryer and gas cooktop and I used 118 Therms, and looking at summer gas usage I'd say about 20 therms per month is hot water, dryer and cooktop.

I haven't looked into rebates or tax credits but will factor that into the acquisition cost portion of the model.

(edit: corrected the hours )