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Home Heating Cost Comparison

efficiencymaine.com

51 pointsindigodaddy60 comments

I was renovating a home 9500 feet above sea level in the Colorado mountains with baseboard heat. The bills were 800-1200 a month in winters because it was an all electric home built before the gas was run in the community.

I reached out the Mitsubishi and shocked they got back to me so quick about how they wanted to prove their hyper heat systems could handle 9500 feet above sea level and getting down to -10F.

Long story short I got all the labor free and the equipment at 60% off and they said if I was unhappy they'd remove the system for free.

100% happy. Heat pumps are the greatest thing because the home doesn't go through this massive hot/cold cycle. They might stay running at 10% once they get to temps to keep it at the temps.

My bills went from 800-1200 in winter to 400ish. The bonus was I got AC during the summers when needed.

I told my wife when out HVAC goes out we are 100% switching to heat pumps

I regret not doing one of those. We saved a couple thousand using a Fujitsu Halcyon that runs well down to about 20F. When it’s running it’s great, but we cut over to oil in late November.

Do you have it setup to run during the daytime when it’s warmer and cut over to oil at night?

> Heat pumps are the greatest thing because the home doesn't go through this massive hot/cold cycle. They might stay running at 10% once they get to temps to keep it at the temps.

That means you have inverter drive. Also nice because they don’t have a capacitor that eventually fails and won’t dim your lights when it turns on. Also great at reducing demand charges if your electric utility bills that way.

But heat pumps can run as an on or off only system. Depends on what you install.

Shoutout to Technology Connections on the topic: https://youtube.com/playlist?list=PLv0jwu7G_DFVIot1ubOZdR-KC...

He apparently has 4 videos on it!

Something quite isn't right, or I'm an idiot.... I put in $8.14 per "Unit" of natural gas (my current cost). One "Unit" of natural gas is 1000 cubic feet, which on the _low end_ contains more than 1,000,000 BTUs (in practice, it's more). That's $1068 doll hairs a year @ the 85% efficiency of "last generation" furnaces from yesteryear.

The newest Natural Gas furnaces are so efficient, that the exhaust pipe is just plain old PVC pipe, not metal, because nearly all of the heat is extracted. These run around 95% efficiency. Sticking that into the calc, that comes out to $971 blonde ones.

What am I missing

What were you expecting to find?

$1068 at 85% efficiency is $907 "effective" heating dollars. $971 at 94% efficiency is $912 so that passes a basic sanity check.

The major improvement is efficiency c es from runnimg higher volume at lower temperature differentials. This allows the "cold" side of the furnace/boiler to condense the water vapor in the combustion gasses and capture its latent heat.

I was thinking the same thing. Never had a furnace cheaper than natural gas, was wondering how they got their figures.

I'm in Wisconsin, and we peak in 90's Fahrenheit with humidity in the summer and will have a week in February where we'll never get above 0F. I know geothermal works up here; we had it in a previous house but we paid (in 2012) $9600 just to have the 4 150 ft wells dug. What would air-source heat pumps look like up here? I've seen very few new homes in my area with them.

The cost is mostly in the installer based on the anecdotes of a well known technology youtuber in illinois. They are scared of installing heat pumps and carrying them allegedly. You may be able to buy compatible hardware on your own and get an installer. But aside from that one week you can get ASHPs that go down to 5F without losing efficiency. You can even get multi-head units that can move heat from where you might not need it (near a fireplace or stove) to where you do (bedrooms) ditto in reverse for cooling. But I'd suggest doing some research.

Thanks. We're considering building our ideal home to live part-time and eventually retire to, and we'd like it to be free of natural gas. Obviously heating w/ natural gas is the norm up here, but induction cooktop, solar water heater, and a heat pump can replace that. The heat pump coupling is the high order bit I need to research. Ground is the pricy but default option.

Check your prices, that's more likely to be a bigger determiner than other things. For me it wouldn't make sense just because natural gas is so much cheaper right now. That is however subject to change. That said if I was installing AC I'd probably still do it just because Natural gas prices have been a touch volatile lately.

If you skip the gas entirely you can make the house envelope tighter since you don't need to pull in cold oxygen for burning and vent the toxic emmisions.

If it's a new build, and you have the ability to make that decision early and adjust everything else, it tilts heavily away from gas or any other combustion within the home's envelope.

The problem is that it can’t do it through the whole season, so you’re playing for a whole second system that you barely use for that week-month.

You may have to install your own because the installers won’t know what to do with one.

> What would air-source heat pumps look like up here?

Air heat pumps dont work in 0F, you need an alternative. My heat pump has resistive heating coils for when it gets cold. https://en.wikipedia.org/wiki/Air_source_heat_pump#Efficienc...

Current models work down to -10F without going linear. They'll still technically work beneath that but are basically the same as resistive electric at that point.

This isn't true. I live in MN and have a mini-split heat pump and a whole home air source heat pump that runs dual duty with my natural gas furnace. I currently run the cut off to switch at 20F. However both units will heat down to -20F. The mini-split struggles at that temp but the large unit still kicks out enough heat for the entire home.

I also replaced two natural gas water heaters with one 80 gallon air source heat pump water heater. It can run fully heat pump but also has coils. A "high demand" mode can run both simultaneously, but 95% of the year I run it in "efficiency" mode which is purely heat pump operation. It costs about $80-90/annually so far.

Vermont, and perhaps Maine as well, have initiatives to transition housing to high-efficiency heat pumps that are still efficient enough to be better than just resistive heating even in negative F temperatures. Obviously they will not be efficient in something like -40F, but I believe nowadays they break even in -20F, but don't quote me on that exact temperature. And even accepting that you'll get <-20F a few days a year, it is likely still a net-energy win, and I would suspect, suitable for use even without a fixed backup system. I'd imagine if it's good enough for Vermont, it would be good enough for Wisconsin. The state has websites listing suitable models that might be a good starting point for you.

Hmm we just got a new furnace and none of the installers offered high efficiency heat pumps. The ones available started to become inefficient at 20F above 0. It really wouldn’t of been practical to get this. Maybe some day.

Unfortunately too even with the spike in prices gas is still significantly cheaper than electricity even with the efficiency. But I was thinking about solar down the road which is the only reason I considered it.

Sure but most of Maine doesn’t have natural gas service. Outside of Portland, you generally may have some gas service along Rt 1. Otherwise, at best you can get bottled propane, but you have to consume a good amount to get decent pricing. It’s usually tiered. This calculators been around for a long time and gave us a pretty reasonable estimate when we did our system.

It’s also not an either/or thing. My house (southern Maine) has oil forced hot water heat, with an older 84% efficient boiler, and a mini split. We have no natural gas service, and propane isn’t cost effective. We run the split through both shoulder seasons, and we turn the split system off when it’s consistently below freezing or oil drops below $2.00/gal (our breakeven point). The heating bill is surprisingly reasonable given the climate. As a bonus we have great AC from the split, and I don’t care what anyone says, it’s needed these days!

Are you in Maine or somewhere else?

Similar story to the other two in this thread- air exchange heat pumps are available that are rated to work below 20* F. In the end, I switched to wood (natural gas isn't available where I am, and propane is expensive). Currently using a high efficiency stove and a gassification mass heater. Our central heating barely turns on in winter at this point, and the thermal efficiency of both systems isn't too far from the propane furnace either. (The mass heater is stupidly efficient, the wood stove only in the 85% range I think).

Your way is the best way. Even if you did have natural, since you’d now not be using it 9ish months of the year instead of 6, the standby/connection charges make it increasingly uneconomical.

I know a fellow who was on oil heat and the nat gas grid was going to extend to them, but they’re going to install mini splits and keep oil as their deep freeze protection.

For everyone understanding german: Here is a DIY enthusiast (Andreas Schmitz) who build a heat pump heating system by himself and has power and heating costs of only 8 Euro a month:

https://www.youtube.com/watch?v=m2mFhj9Uj6g

Very impressive channel though, non monetized.

What? He's using LG and Mitsubishi heat pumps, has a relatively large battery pack installed that's connected to his solar panels. All of these need considerable investment for a layperson to install.

Absolutely... but keep in mind that these are long term investments AND he has not calculated days, where he changed stuff and had basically no income.

This DIY@yourhouse stuff is also not for everyone and in worst case scenarios it is dangerous. But still impressive, what he achieved in my opinion.

Wood is technically "renewable", correct, as it is non-fossil?

Are there ballpark numbers available for forested acreage per thousand square feet of home living in, say, Maine, in order for the heating needs to be completely satisfied by the land on an ongoing basis?

It’s renewable but does not burn cleanly (pollutants).

Sure, but so do natural forest fires. Aren't trees growing and burning down a natural full cycle with zero overall greenhouse emissions impact?

“ When wood is burned, the combustion reaction produces heat and emissions in the form of water, organic vapors, gases, and particulates. The emissions of most concern are carbon monoxide (CO), carbon dioxide (CO2), sulfur oxides (SOx), and nitrogen oxides (NOx). Other regulated elements and compounds, such as mercury and hydrochloric acid are measurable in the emissions but at levels much below accepted maximums. The composition and quantity of the emissions is dependent on the combustion temperature. Higher temperatures encourage complete combustion and result in cleaner emissions (up to 1300 celsius). At lower temperatures the emissions can also include volatile organic compounds, relatively high levels of CO (a product of incomplete combustion), and more particulate concerns. The NOx (if kept below 1300 celsius) and SOx emissions from burning wood are much lower than those of the fossil fuels coal and petroleum products, and comparable to those of natural gas. Particulate levels in wood emissions are similar to those from burning coal and petroleum and substantially higher than the levels in the emissions from natural gas. Particulate emissions can be controlled to acceptable levels with smoke stack equipment such as scrubbers, bag filters, and electrostatic precipitators. This equipment is however only cost effective on large commercial-sized combustion systems. Particulate emissions from smaller equipment, especially residential-sized units can be a concern. More and more communities and air control districts are placing restrictions on respirable-sized particles (PM2.5 or particulate matter smaller than 2.5 microns). Uncontrolled emissions from wood combustion are high in PM2.5. The CO2 in wood combustion emissions is considered “carbon-neutral” because the amount of CO2 emitted during combustion is basically equivalent to the amount of CO2 trees need to grow the same quantity of wood. Hence the combustion of wood does not contribute to the net increase in atmospheric levels of CO2 (a greenhouse gas) as does the combustion of fossil fuels.”

https://wood-energy.extension.org/what-are-the-air-emissions...

Contemporary stoves are pretty clean.

My brother in law put in a wood burner in Minnesota. He just volunteers to process downed trees on private property within 50 miles. He also cuts down trees basically for free, and takes any municipality-cleared trees from, say, highways. The city just knows to drop them off, but that's a small town thing.

I think he stocks 15 chord for winter, and usually cuts about 40 chord in a few days with a mechanical splitter. He's got several years worth of timber and logs drying on his property. So the hard part is building the timber supply, letting it dry. I think it's fairly easy with the right equipment to build your fuel supply from that.

You don't get too much colder than MN, so I'd see what kind of land it would take to harvest 30-ish chord per year if you wanted to grow yourself.

I'm in New Hampshire. I get about half my heat from wood. I use two cords per year.

That's certainly less. I bet Op could get away with 4 to 6 then. Subject in my post has a large 5br old farmhouse style place, also heats house, water and garage off same unit.

One of the richer men around here a century ago had a mountainside castle. He burned a hundred cords a year. He has a single employee who cut, hauled, split, and fed all of that. In the summer me also mowed the lawns.

And his central heating system was considered to be state of the art.

Insulation, not so much.

I can’t answer your question, but I’m assuming Maine, with its big forestry sector, produces a lot of relatively inexpensive wood pellets which are made from mill byproducts.

The old rule of thumb is a cord of wood can be harvested per acre per year.

You can either spot clear cut or selectively thin to get that cord.

Quick Video about the rocket mass heater. I'm guessing the cost to heat with wood, would be even lower if your house was built around this. https://youtu.be/fwCz8Ris79g

Cheaper solution:

https://www.amazon.com/Selkbag-Original-6G-Wearable-Festival...

Wouldn't have expected Wood to be the most cost effective option.

One has to think of the overhead.

Cutting and stacking(or picking up/delivered), the space to store it, having to carry it into the house, emptying your ashbox, having to actual start the fire, etc.

But man oh man it is hard to beat the ambiance. I have heated exclusively with wood for the last two winters and completely agree with your comments but I wouldn’t trade it for anything.

Heats thrice

Four.

Cut/haul, split/stack, move to stove, burn.

I move two cords - about four tons - a year through that cycle - into my house and stuff it into a one foot square hole in the stove. Love it.

At least four, and the hard labour is usually in summer for me, when the heat is a negative.

Trying burning hedge (Osage Orange) and you'll quickly see why! It burns so hot it can damage light duty fireplaces. Osage Orange thrives on abuse and grows wherever it can in the midwest.

There are extremely efficient wood systems available that automatically throttle up/down, you set with a thermostat, and only need to be fed another bundle [edit] of wood once every few days. The ashes are automatically kicked to a can that you empty once a month. It's quite extraordinary how far these systems have come.

I am guess that’s a typo because a cord of wood is 128 cubic feet, which would be a real big furnace.

You’re correct, I meant a bundle every few days. A cord lasts some people an entire season.

I had never heard of a cord as being a unit of measure. It’s 3.6 cubic metres in my units, which is easily a season for me (in a much more mild climate).

A cord is apparently the length of a piece of string. That’s the second ridiculous unit of measure I’ve encountered today - shoe sizes are incremented by in barleycorns.

Cord is used all over the us/Canada, not sure if it’s European

The electricity costs are pretty high in these estimates, by 3x or so.

You can adjust them for your region.

They appear to be localized to Maine. I'm pretty sure mine is cheaper for natural gas.

3x is probably only for Pacific Northwest. I would be curious to know where else electricity is $0.08 per kWh.

Seattle is 0.10. Love it.

Manitoba Canada is $0.093 CDN a kWh, that’s about $0.071 USD.

It’s mostly hydro electric here, so much so that it’s not called your ‘electric bill’, it’s the ‘hydro bill’.

Yeah, I pay 0.07$ in Portland OR

New York / New England electricity costs are about $0.25 to $0.3/kWh these days unfortunately.

That sounds cheap to those of us who suffer under PG&E.

For context, electricity costs in some places in the EU are currently at $0.8/kWh (including taxes and other costs). The war significantly inflated these numbers, last year they were around $0.3/kWh.

I think that is the delivered cost, not just the cost of the electricity (which is only about 45% of the cost here in New Hampshire).

We have an oil boiler and wood stove. This year and last we added Mitsubishi hyper-heat heat pumps. The wood stove is great, and cheap to operate, but in the ~4 mos. of the shoulder seasons, it often doesn’t make sense to fire up the wood stove (when it’s only cold in the mornings). This is where the heat pumps shine. This winter we will only use the oil heat when the temperature is below 25°F as per this [1] Mass Save site. A bonus of the heat pumps is the AC in the summer, which we now need about 2 mos. of the year.

So we are effectively deprecating our oil boiler. In the next year or so, we may pull out the indirect water heater (which is powered by the boiler) and replace with a heat pump water heater. Then in ~5-10 years when our oil boiler is at EOL, we will likely replace with wood pellets.

[1] https://www.masssave.com/learn/blog/residential/5-tips-to-ma...

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