Heat Pump Cost Comparison: Winter heating vs. Gas Furnace
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- เผยแพร่เมื่อ 14 ต.ค. 2024
- In this video I compare the winter heating cost of gas furnaces with that of heat pumps. I was able to do this because I have been in my house for two winters; the first with natural gas furnaces and then the most recent winter with brand new heat pumps. I'm paying less to heat my home with heat pumps than I did before with gas furnaces and in this video I share all the details and the numbers.
I share not just the costs but also the exact number of therms and kilowatt hours (kWh) used.
I'm in Las Vegas, NV, which gets colder than most people think it would in winter.
If you live in any of these cities your winters are fairly similar:
Atlanta, GA
Austin, TX
Birmingham, AL
Dallas, TX
Phoenix, AZ
Sacramento, CA
San Jose, CA
San Antonio, TX
I've posted full details of this comparison on my blog, and you can even download the data for yourself! theheatpumpguy...
Thanks for watching! If you enjoyed this video please consider subscribing to my channel.
Thank you for detailed analysis, I was trying to find something like this I couldn’t so far.
Great info, thanks Scott! I installed a heat pump system in my house last year and save a bunch of money, and I live in Flagstaff, much colder than most places in the country. I installed solar panels on my house several years ago, which made our power bill go to $0, which also charges our EV. Part of the beauty with heat pumps (most), is that you get AC and heat, and of course, you can produce your own power to run them, something you'll never do with gas or oil heaters.
I stumbled on this video and interestingly I am considering doing exactly what you have and we live In flag as well. What I’m wondering is how well your heat pump worked during the super cold days. My hvac guy suggested having a two stage system with a gas furnace for the times that it’s too cold for the hag pump work work effectively. We are going to install solar and my hopes are to eliminated all of the power bill and most of the gas bill.
In southern California, electricity sells for 36 cents per kWh. It's much less cost to use gas there as the price of gas is about $1.15 per therm. A therm vs a kWh are not the same so there is a conversion formula to figure what amount of gas is needed to generate the same amount of heat as 1 kWh of electric.
Thank you and my condolences! I live in New England and my electricity is about $0.26/kWh (including all fees). I get sick of hearing $0.12 average or $0.09 in some state or another. 1st time I've heard of an area with higher costs! Now I feel better. And Floridians or wherever, enjoy your cheap electricity but buy flood insurance, you need it! (just a pre-emptive shot before someone comments and gloats about how bad New England is -- more accurate would be there are drawbacks in every area).
@@massengineer7582 Southern California electric rates with SCE currently are 38 cents for about 1,800 kWh or less and 48 cents for everything above 1,800 kWh. Nevada power costs 6 cents and then 8 cents ! Interesting how produced power is fairly even in cost to make yet the politicians and the "regulators" figure out ways to cheat and bilk the public with extreme rates.
@@Garth2011
Electricity rates have sky rocketed in last 10 years in CA, it’s insane.
@@gund89123 Just for comparison. Nevada power sells for 6 cent, tier 1 and 8 cents tier 2. Thats 5+ times less and sourcing the power and transporting it is all the same except that California has ISO, the power grid manager in Rocklin, CA. Folks are being "taxed" by the state through utility bills, grocery fees, gas taxes, property taxes, fees for environmental hype and on and on. Fake reasons to tax and fee everyone to death.
What’s the efficiency of your gas furnace and heat pump? Thank you for sharing the data
From new england and kwh where we live is going up to .41 in January 2023. What I get from this thoughtful and well produced video is that heat pumps can be cheaper than gas if you have an 80% inefficient gas furnace, cheap access to electricity and very moderate Winters. I enjoyed the video but the rule of thumb has been that efficient gas heat is 4x cheaper than old toaster style electric heat. And the best heatpump is 4x cheaper than old toaster style electric heat - these articles are usually based on the phantom national average of .135 kwh so there ya go. Heat pumps systems are least twice as expensive to purchase install where I live as well with less expected year. As far as saving the environment - our electricity is mostly from natural gas anyway. I doubt this electricity produced and delivered is equal or better than a high efficiency gas furnace.
You're right to point out there's a lot of factors to take into account. And big variations in both electricity and gas pricing regionally is part of that. I think a good rule of thumb though is if you're heating with propane or oil, then a heat pump will for sure save you money. Natural gas is not as clear cut.
@@ScottAllison I agree with you 100%. I even have solar but I still end up paying for electricity so anything a heat pump adds for electric usage will be at whatever the full rate is. I guess I might be a bit defensive because there seems to be a unified message/push (not from you) that heatpumps are less expensive to operate than anything else. I can't make heads or tails of the heatpump vs X calculators but mostly I seem to just come out cheaper on the AC side (high seer) not on the heating side. Natural gas prices are shooting up too so who knows but our electric is made from natural gas too so you probably can't win.
Thanks for this share, we found CA gas prices took a big jump winter of 23 as CA had to import much more gas and the prices went up. Our winter payment went up 150% due almost all to gas. We’re in solar contract and of course, here in the dead of winter (same temps as your presentation, central CA coastal hills), our 30yr-old gas heater gave up. We’re getting strong suggestions from PG&E to go with a heat pump. Thanks again for the data.
Glad it's useful to you! Yeah, if you have solar a heat pump really is the way to go. There's now tax credits if you buy one making them even more attractive.
Well that was an interesting collection of trivia, Scott. I commend you for your record keeping. The depth of your analysis however leaves much to be desired in terms of settling the issue of which costs more where and when. You've already gotten too complex for most people, sadly, but there's more and the variables are many. You're looking at operation energy cost alone per winter for two different winters with either technology. Energy costs aren't constant, nor are winters. Gas provides a specific heat energy per unit measured and charged for, but a heat pump varies in heat energy output per unit of electrical energy input depending on the environment at the moment of measure, most notably by the difference between the temperatures between where the heat is being moved from and to. It's much more efficient at converting energy consumption to heat when that difference is small. At some temperature difference increase, given the every costs at that moment, the energy efficiency drops to the point where it becomes equally costly to use either technology. That's the crossover point. Further, and the gas becomes the less costly source.
So for energy use costs, rather than limit yourself to one or the other, have both and switch back and forth when crossing that point.
Your analysis also fails to take into consideration the cost of putting the equipment into service and maintaining it. There's easily overlooked, yet quite important to a proper cost analysis. And the time value of money.
The same applies to everything including home solar installations where I've seen many cases of people paying so much up front for a breakeven date twenty to thirty years hence, and that's if all the equipment is still working the same then, no costs for maintenance and repairs. Big assumption. And a lot of those people end up moving before the savings can be realized.
And of course if they had invested in Microsoft, Apple, or similar instead...
Pretty fair video . Afraid cost don't stack up well in uk . Installation massively expensive . And electricity is 4 x that of gas per kwh . Plus I like to get up to a cold house ( I sleep better ) and then heating goes on for 14 hours ) so I like the greater energy available with gas.
What I would like to know, how much was invested in solar and storage?
What would be cost with these investments?
Besides, as someone mentioned, you have no winter. In my situation, in Ontario,Canada picture is way different. Price of electricity high, natural gas is not expensive.
Temperatures way too low compare to your area.
So in my case, and many Americans living in cold states, this is completely different story.
The US and Canada are far behind Europe and Asia where heat-pumps are common. It's even hard to import them here. Heat-pumps + Solar PV can drastically reduce your heating and cooling costs. They also shave peak load away from the grid when it's needed most on hot summer days.
Gas is cheaper in US compared to electricity.
Energy is cheaper in US.
That’s why it doesn’t make financial sense to invest in insulation, heat pumps.
Interesting comparison, thank you. My intuition suggests that the better insulated a home is, the less it matters whether you use gas or electricity for heating. Does this jibe with data you’ve seen in your work?
I don't think that is really a factor. If the home is less insulated it's still going to need the same amount of heat to warm it, whether it's from gas or electricity.
@@ScottAllison : Thanks, Scott. I guess the point I was trying to make is that the amount of energy needed to heat or cool a house becomes smaller and smaller as the house becomes better insulated to the point that the cost for different types of energy (gas, electricity, etc.) becomes insignificant. - Cheers!
Hi Scott, when you did the analysis why did you not include the electricity cost of running the gas furnace. It takes both electricity and gas to provide heating with gas. Running the air handler is included in the cost of the heat pump but not in the cost of using gas. It seems the savings using a heat pump should be somewhere between 50% and 80% of the cost of natural gas that is no longer being consumed when using the heat pump. And if you have your own solar (and a battery system in the garage) the savings would be even higher than that. Any comments?
That's a really good point. It never occurred to me to add that in!
This was excellent. Thank you so much.
You're very welcome!
The outside condenser for the heat pump system will be working almost 247. Its going to need major parts or replacement within 10 - 12 years. All those savings from last 10 years will be spent on parts and replacement. I see no benefit to upgrade to heat pump system unless the systems can last at least 20 - 22 years and if you have enough to install an electric power wall and solar roof.
This video was very informative. Thanks Scott.
I am in Bay Area and I am looking to execute a similar project for my 1992 built home. I am looking to benefit from your experience.
When you made this switch to heat pumps, did you replace the ducts - particularly the ones in the attic - or reused the existing ones ? If reused, how did the installer ensure that the new air handlers were a good match for the duct system , like cfm, static pressure etc ? New Fujitsu air. handlers being variable speed, I am not sure if they will work as well for the old duct system designed for single speed handler .
Also, were the outdoor units same BTU / ton rating as the old furnace/ac they replaced ? Did they run new line set or reused existing one ?
Your experience will help me ask the right questions to the installers I am going to talk to .
Thanks, I'm glad you found the video helpful! You've asked a lot of good questions, so let me try and address them. My house was built in 96 so they're both about the same age. The existing ductwork was reused, with some minor modification. The line set were not, as Fujitsu requires a different diameter than the standard R22 ones. I was happy with that anyway because the previous lines were in the wall and vibrations from the old condensers traveled up those lines. The new ones are mounted on the outside of the wall and covered with a line set cover painted to match. Unfortunately I didn't fully appreciate the requirements of static pressures at the time I was getting quotes but if I had I would've asked more questions. A couple of contractors said the return was too small and indeed, I verified that myself later and they contractor came back to replace it with a bigger one. So I'd start with that. If you haven't already looked at your return and ductwork take a look. Assuming they're all done with flex duct, get a chart online that shows flex duct diameter and airflow in CFMs. Measure the diameter of your return and supply ducts and then add it all up and see if it's appropriate for the system size as well as balanced on both sides. My return in particular was undersized likely because the original systems in the house were undersized. We knew that because the pads that our old system sat on were slightly too small. The previous owners of our house replaced those with a 3.5 ton downstairs and a 4 ton upstairs. All the contractors who quoted did it based on 2 x 4 ton systems, since half sizes usually aren't available with variable speed systems. None did a manual J. I did one myself, but I also knew based on the previous systems they were sized about right (based on run time per hour in the coldest and hottest days). From memory the 4 ton Fujitsu air handler has an airflow of 1640 CFM on high, 1020 on medium and 820 on low. Ours almost always runs on low as FYI. I haven't measured the static pressure, and neither did any contractors, but I have compared the power consumption with the fan running at those 3 speeds with the power listed in the spec and it's reasonably close so I'm not concerned about static pressure. Before they came back to upsize the return the power consumed when the fan alone was running was way higher than spec, confirming that the static pressure was too high. Hope this helps, and that I covered everything! Oh, the previous furnaces were 80k BTU but the 4 ton fujitsu tops out at 53k. But I wasn't concerned based on the manual J I'd run and I also knew that the run time with the old gas furnace tended to be very short. I prefer the slightly cooler output over a longer period of time now with the HPs.
@@ScottAllison Thanks a lot for your prompt reply. I sincerely appreciate it.
one question that is still lingering in my mind is about whether to replace the ducts. I am told that the flex ducts have a useful life of 30 years and so, this may be the time to do it. Replacing the ducts in the attic should be straightforward, but that for the ones buried in between the floors for the 1st floor ( I have slab foundation and no crawl space ) may be too destructive and costly . This reason alone keeps me thinking about going ductless and leave the old ducts and the functioning gas furnace as backup.
what would you advise for that ? Did someone suggest you ductless option and if yes, did they point out its possible demerits , as I keep hearing that ductless is not a good option for large homes.
No one brought up ductless. I think while they're very efficient, to do a whole house with them, especially one that's 3000 sqf costs a fortune, not just for hardware but also the labor which is huge. Much more cost effective to use existing ductwork. No one brought up the age of flex duct as a problem. Visually, what I can see in the attic seems fine. I would have the same problem as you that the downstairs would be a huge messy job to replace.
Scott, I suggest you add the metrics of Heating Degree Days (HDD) and Cooling Degree Days (CDD) to your analysis and discussion. HDD are far more comparable and accurate in discussing heating costs. FYI, Los Vegas has similar heating to cooling loads at around 2700 HDD/CDD. In your analysis, it seemed the assumption of 80% efficiency of the gas furnace was a bit low. Did that assumption come from recent studies? Thank you very much for posting your data, and for your post in the NY Times.
Thank you! Appreciate your feedback. Do you know a good source for the HDD and CDD data?
@@ScottAllison I have seen that info on my energy bill before i would start there if i was you
Where natural gas and electricity are both way above national averages in price, our strategy next winter is to use less of both. Our house could have better passive solar gain than we have been capturing, and we could more efficiently heat our bodies than heating the house/air in the house. More merino wool & foot warmers, and I’m looking for an efficient way to warm my low back (my most sensitive body part to cold!)
I'm in Vegas and I'm being told that heatpumps will only have half the life as an A/C since you're using them during the winter months as well. That means a $6k install that would last 20 years for a roof package unit will only last 10 years. I most likely will go with a gas fired roof package until they can make the heat pumps last longer due to the increased usage expected of them.
Yeah I've heard that very same thing from installers as well, and it's partly true but it's an exaggeration. I have the data, and because of our climate here the systems run ten times as much during the cooling season than during the heating season. So maybe at a stretch it takes a year or two off the life span, but it doesn't half it. It's possible that in fact it prolongs the life. Instead of sitting idle for 6 months your outdoor unit gets some use every day. Cars definitely benefit from being run every day. Maybe it's not a good comparison but it's not impossible.
@@ScottAllison That's a good point on having the appliance not sitting idle during the winter. Thanks for the fast response!
I’ve had both, and the heat pumps have always been more problematic.
Thank you for useful information.
Glad it helped!
Appreciate the info, it's just what I was looking for. Thanks.
Also, I can't believe how many of the viewers are so critical...How about they do some research and link to it instead of telling you what you should do different. lol
Glad it was helpful!
SAN DIEGO just doubled their natural gas prices. Heat pump sounds more ideal right?
Almost certainly! Depends on the differential between gas and electricity costs, and I guess electricity prices are also up there too. But probably not double.
thank you!
But wouldn't you still get the electric credit if you had gas and sold the solar power from the panels? I mean you got to pay for the solar and batteries somehow, right? What was the seer rating on the original gas furnace? 17 seer is on the high end.
SEER is a rating for cooling, gas furnaces have an efficiency rating in %. I made an assumption the original gas furnace was 80% but it could've been less. Anyway, to answer your question, yes I do export electricity back to the grid sometimes, but the utility only buys at 75% of their retail price. So It's better to use the electricity you produce! So that's what I'm doing now, during the winter the electricity I generate is used to power and heat the house.
Thanks has anyone done this for Upstate NY/New England/Minnesota/Northern states locations? I've been looking at research that suggests gas vs ASHP is close on pollution (sometimes either way, depending on temps, units) and ASHPs are about 20-40% more expensive, though both much cheaper than oil/propane.
Good question, I haven't seen a comparison for those states. But you're right, it's definitely cheaper than oil or propane. As far as pollution is concerned, it's completely down to how clean your electricity is. In general electricity is cleaner than burning natural gas, as so much electricity is produced now without the use of fossil fuels.
Use both, plus wood.
I looked at your spreadsheet and it had an unusually high monthly avg natural gas usage of 75.2 therms . This converts to 7271 CCF. CCF is the unit gas companies use in their bill. Was your usage this high?
You're off by a factor of 100. 75 therms is approx 72 ccf. And that's very normal usage for a 3000 sqf house.
CALIFORNIA IS 0.3$ PER KWH OR 0.46$ IF TIME OF USE
Holy shit that's expensive. $0.10 to $0.14 in Virginia.
On the tiered rate plan it is 36 cent tier 2 and 46 cents tier 3 per kWh. Complete rip off and very politically run. Nevada tiered rates are 6 cents and 8 cents for tier 2.
@@Garth2011 we are in Central California and trying to decide between a minisplit or gas furnace. We had to rip out our old floor furnace. Looking how PG &E just raise rates by 75% I'm thinking we should probably stick with natural gas.
@@1to10KS This is where I have to draw a line. When large companies determine they need to increase prices "to keep up" and they raise prices that exceed any reasonable source for inflation by 2 to ten times, you have to ask, where do they figure that is what they must have to be "competitive" or inline with costs. I know of no company that sits on its butt for years and years then suddenly discovers they are behind by 75% as in this case. Who runs a company that far off?
The only answer this this is they have a captured audience of customers who cannot go to a competitor due to the territory they have AKA monopoly and the state allows this. In fact, its my estimation that the state of California is running PG&E just as much as they are running the CPUC and CA ISO. FYI, SCE or southern California Edison, has doubled their rates in just the past 9 to 12 months. We are presently paying about 6 times more for electricity than those in Nevada. Rates in NV are 6 cents and then 8 cents in tier 2.
@@1to10KS I would use natural gas and when you purchase your unit, I'd also recommend purchasing brand new spare parts that will wear out most often. One day the state won't allow a gas furnace to be "replaced with gas" but it can be repaired otherwise it has to be replaced with electric. There is no reasonable option to use electric heating since it simply costs too much to operate. I'd even recommend natural gas air conditioning condensers if you can find them. The cost to run those is pennies compared to electric.
You didn't tell us how big your systems are.???? BTUs????
Both 4 ton. 45.6k BTU cooling . 53k BTU heating
Do you have electric water heater?
No, that's gas
Will probably put in a heat pump water heater when the gas one dies
646 kWh per month is heat pump only, not total electricity consumption correct? (Eg. Other appliances like dishwasher)
@@samchheda correct
@@ScottAllison how did you disentangle gas used by the water heater vs the furnace?
The noise of heat pumps is really annoying if all the neighbours suddenly get one. It’s a constant drone of noise pollution. Gas is much quieter. Winters used to be so peaceful and quiet until all the neighbours got heat pumps that make a constant drone noise yet only save $10 per month.
That's a fair point. I think the answer is more cities should put in place a noise ordinance for outdoor units like Seattle has. Quiet models do exist, I have a video of mine. The savings on running costs for heat pumps can be massive though, especially if you're currently using propane or oil.
You do not have a winter.
Shouldn’t you explain cost of solar/battery installation as I’m sure it wasn’t free and if the system was financed it too would have a monthly cost. So yes when a system is supplemented by solar you’ll use less grid power but did you actually save money month to month in the short term I doubt you actually save money due to the cost of solar/battery setup
In this video I focus on standard rates charged by utilities, so the analysis doesn't focus on the solar/battery aspect. But yes, of course that did cost a lot of money.
Las Vegas winter ❄️ lol
It gets cold here!!
@@ScottAllison Relatively speaking.
Your Irish right
Close. Scottish.
@@ScottAllison ah cool
Appreciate the attempt at doing a true and fair data-driven comparison - feel like we need more of that these days. Unfortunately your obvious bias push this right back to the activist / propaganda side of the fence for me. Wish you would have just stuck with your own anecdotal example and cost comparison.
To wit: 18 vs 33 states... "and of course that's using my numbers so this may not be a fair comparison, BUT I JUST PUT THESE NUMBERS OUT THERE"
What??
In what world is that a justification for knowingly putting out obviously incorrect and misleading numbers comparing the rest of the country?
Somewhat irresponsible for someone who is seemingly trying to further awareness and knowledge of heat pumps.
Hey I got a good one why not set the temp to 48 degrees and make bigger savings
70 degree tempature is "no heat" we live in the real wourld and no solar also gee I wonder why you had gas to start with