Share Your Home Electrification/Efficiency Improvements

iPlug said:

Out of curiosity, have you calculated how many therms or kWh or other units of energy in coal you use annually with your forced air coal furnace?

Click to expand...

My coal furnacewas built in 2014, I bought it in 2018 on clearance. I didn't pay anywhere near $4,000. With sales tax it was nearly $800.
Originally with sales tax, it would have been just about $4,000.

I didn't buy the coal in new mexico it's very hard to get unless you are over by Arizona or the 4 corner area. I collected over the course of several road trips returning home
through central texas.

I use some where around 1.5 mm btu of coal last year.
Around 90% of what goes into the coal furnace is construction waste lumber, pallet pieces. Most importantly it's free, but lots of nails.
Most of the remaining 10% is plain firewood from chopped up trees, then almost all of those were cut down by the electric coop.
The anthracite coal I use burns far cleaner than any of the wood I burn.
I will probably use the kill-a-watt meter to track power use by the furnace. It knocks at least a mega watt hour or 2 off the monthy power bill running the coal furnace compared to the heat pump with electric heat enabled.
The coal furnace blowers use almost no power compared to the heat pump.
It will have definitely paid for its self in its 2nd year of operation, if it gets cold this year like it did last year, in the 2nd week in October it will pay for its self before the end of this year.
This winter I am going to make the coal furnace closed loop. It will greatly boost efficiency. Less fire wood to collect, less coal to buy. I bought a metric ton of coal and that should last around 10 years, baring no unusual events like another week of -10F nights.

I got the coal furnace because it was almost the same price as the more lightly constructed equivalent model of wood furnace. Plus I can burn the hottest and fastest burning types of coal if I want. I have heard they can burn tires too.
Plus just saying the words "coal furnace" sets people off.

Here is retail coal in Texas
https://www.tractorsupply.com/tsc/product/premium-nut-coal

899 cents for ~ 18 Kg
If it is 7 kWh per Kg then
899 cents / (18*7) = 7.13 cents a kWh, taxes not yet included

Compare that to as low as 0.5 cents a kWh in a PV/Heat-pump arrangement.

Burning coal amounts to paying through the nose to pollute. Something only an Oil-y would do

SageBrush said:

Here is retail coal in Texas
https://www.tractorsupply.com/tsc/product/premium-nut-coal

899 cents for ~ 18 Kg
If it is 7 kWh per Kg then
899 cents / (18*7) = 7.13 cents a kWh, taxes not yet included

Compare that to as low as 0.5 cents a kWh in a PV/Heat-pump arrangement.

Burning coal amounts to paying through the nose to pollute. Something only an Oil-y would do

Click to expand...

Did you read the part where nearly 100% of what goes in the coal furnace is waste lumber and nuance trees?
Or read the part where I said a "a metric ton of coal should last around 10 years"?
Do you even know how a heat pump works in cold weather?
It appears the answer would be no to all.
It also appears you don't know nearly as much as you think you do.

When it gets below freezing most heat pumps start using some electric resistance heating to keep the oil for the compressor warm. Even the super efficient ones are all using at least some resistance heating by +20F.
At freezing mine uses a compressor heater and will briefly cycle the resistance heaters on and off to boost the discharge temperature.
At +5F mine gives up trying to be a heat pump is using backup resistance heating only.
Resistance heating is 9 cents per kwh.
So how's that cheaper than burning coal for around 7 cents a kwh of heat?
Thats assuming I was burning coal.

Electricity here is about 9 cents per kwh on my bill on average.
The the coal furnace peaks at 180,000btu per, the blowers run a fixed 450 watts. The way I like to run it burning wood makes some where around 50,000 btu per hour.
50,000 btu per hour to over 100,000 btu per hour.
So paying less than 5 cents for electricity to get 50 to 100kwh btu of heat.
That's 15 to 30 kwh of wood heat heat per half kwh of electrical input.
I do have a heat pump, I use it some on mild winter days, but would rater keep it off.

I burn coal on unusually cold nights because it burns for a long time, easily through the night.
The coal furnace is plugged into a slightly used but free UPS, so when the power goes out the coal furnace keeps going.

^^
I commented on the cost of burning coal.
Burning free "waste" wood is obviously no cost to you out of pocket immediately, although you WILL pay along with everybody else for the pollution and AGW. "Waste" wood should be recycled into the ground. You may not have noticed that you live in a shithole because those before you burned down the trees and turned the land into desert. It is time for you to catch a clue that burning bio-matter is REALLY, REALLY stupid.

It is you who do not understand how to use a heat pump efficiently and cheaply. The idea is to heat when the ambient air temperature is highest, and to keep the warmed up air in the home with a decent house envelope and HX for air quality.

Oilpan4, your listed zipcode shows as Cannon AFB.
January shows as the coldest month there, with average low of 26ºF according to Mr. Google.

Our coldest temps are also in January. Here in Rocklin, CA the low average for that month is only 38ºF, although we get a few winter days with a few hours in the pre-sunrise time of 25-30ºF.

Last winter was the first cold season for our new central air ducted heat pump. We have a 2,550 ft^2 house and it used a tad over 1,800 kWh that season.

Although we often turned the thermostat down to ~68ºF when we went to bed, we would often bring the temps back to ~70-72ºF around sunrise when getting up. We left the heat pump in heat pump only mode, but the system still automatically ran resistive heating a few times for a total of 6 kWh that season while the coolant circuit briefly ran backwards to de-ice the coils on the coldest pre-dawn mornings.

I, with 2 assistants and great, often frustrating effort, installed the Mr Cool DIY mini split in my bedroom only. I have always had trouble with my room being too hot in Summer, and too cold when the wind is from any direction other than West or due North in Winter. I can now chill my room 5F or more in 15 minutes or less, but the thermostatic controls are crap, and I still have unpredictable temp swings - this time unrelated to wind direction, at least in Summer. Part of the problem is with locating the main temp sensor in the unit, near ceiling level. I can choose to use the remote to sense the temp for a few hours, but that has a crappy sensor. I'm disappointed. It is, however, very quiet, and seems to use only modest amounts of power.

LeftieBiker said:

...the thermostatic controls are crap, and I still have unpredictable temp swings - this time unrelated to wind direction, at least in Summer. Part of the problem is with locating the main temp sensor in the unit, near ceiling level...

Click to expand...

Sorry to hear. Is it more than that the ceiling temps read higher than what occupant level temperature is, or main sensor just not accurate, or unit unable to respond to sensor data with a reasonable temperature band, or something else?

iPlug said:

LeftieBiker said:

...the thermostatic controls are crap, and I still have unpredictable temp swings - this time unrelated to wind direction, at least in Summer. Part of the problem is with locating the main temp sensor in the unit, near ceiling level...

Click to expand...

Sorry to hear. Is it more than that the ceiling temps read higher than what occupant level temperature is, or main sensor just not accurate, or unit unable to respond to sensor data with a reasonable temperature band, or something else?

Click to expand...

There are two issues, I think. The first is the location of the main sensor, that high up at 7'. The air temp up there drops over time as the unit runs, but more than it drops in the lower part of the room. The sensor in the remote reads 2F high for a few hours, then gets fairly accurate, but is also subject to breezes. I run the fan on Low usually to combat this, but I have yet to maintain a set temp for more than a very few hours. I go to bed cold and usually wake up either freezing or sweating. I may look into wiring a standard wall thermostat to the damned thing, overriding the built in sensor. I'm hoping it does better with heat mode, but I don't see why it should.

LeftieBiker said:

There are two issues, I think. The first is the location of the main sensor, that high up at 7'. The air temp up there drops over time as the unit runs, but more than it drops in the lower part of the room. The sensor in the remote reads 2F high for a few hours, then gets fairly accurate, but is also subject to breezes. I run the fan on Low usually to combat this, but I have yet to maintain a set temp for more than a very few hours. I go to bed cold and usually wake up either freezing or sweating. I may look into wiring a standard wall thermostat to the damned thing, overriding the built in sensor. I'm hoping it does better with heat mode, but I don't see why it should.

Click to expand...

I wonder if a small ceiling fan set on low and updraft would solve your issues? I've done that with a crappy window unit in a small bedroom and it made quite a difference - stable temps throughout the room with a little, comfortable air circulation. Don't know what the watt draw is, but cannot be much.
To add - the room has vaulted ceilings that trapped heat coming thru from the roof - probably added to the issue when the A/C fan came on and pushed the hot air around - my assumption

+1
Nice suggestion

I use several smaller fans (one on a timer, one on a thermostat) to help me get to sleep, and to stay in the temp range I can tolerate. They mix the air quite a bit, but that just seems to confuse the mini split. Still air over many hours is most likely to yield a stable room temp. Add to the mix our central A/C, which I've found I still need to control the humidity (the mini sucks badly at that) and I'm in the same boat as when I started - just with a much quieter system freezing me and soaking me with sweat...

Yes, I have tried closing the house air duct completely. I get 70+% humidity.

It drops down around 0F here most years.
Last winter no 0F nights but winter started the 2nd week of October by plunging us into a week of +10F nights.
In 2010 when I first moved here we were slammed with about 8 days of -10F nights, then for the finally it hit -16F . I later found out excel was expecting the power grid to fail, to the point where they started calling in crews.

I'm going to keep burning wood.
At least I'm not a natural gas user for all my home heating.
No one cut down all the trees here. That's the dumbest thing I have heard in months.
High desert tends to not have many trees.
There are more trees here now because people plant them and bring water to the surface.
On the east coast I could drop a tree in the ground almost anywhere and it would grow just fine. Here I have to shield them from the wind, give them partial shade and water constantly in the summer. The sun, heat and wind are always trying to kill my new trees.

I have a 40 foot tall tree that I'm cutting down to make room for my solar panels. Then I'll cut it up and jam it in my coal furnace this winter. Millions of nearly free BTUs of concentrated solar energy, nutrients and water from the septic tank leech field.

SageBrush said:

^^

It is you who do not understand how to use a heat pump efficiently and cheaply. The idea is to heat when the ambient air temperature is highest, and to keep the warmed up air in the home with a decent house envelope and HX for air quality.

Click to expand...

I forgot you are the expert on everything.
So how do I use my heatpump efficiently when it's 5F out side at night and the heat pump compressor will not even come on?
You said I don't understand, so clearly you do. Why don't you impresse everyone with your heatpump expertise.

Excellent Thread!!!

The above post looks suspiciously like pre-spam. I hope not.

Oilpan4 said:

SageBrush said:

^^

It is you who do not understand how to use a heat pump efficiently and cheaply. The idea is to heat when the ambient air temperature is highest, and to keep the warmed up air in the home with a decent house envelope and HX for air quality.

Click to expand...

I forgot you are the expert on everything.

Click to expand...

Compared to you, that is not saying much.

So how do I use my heatpump efficiently when it's 5F out side at night and the heat pump compressor will not even come on?

Click to expand...

Read the quoted post. Again. And Again. And again. Eventually it might sink in.

You sound exactly like a heat pump sales pamphlet.
Ambitious, nonspecific and completly useless.

Oilpan4 said:

You sound exactly like a heat pump sales pamphlet.
Ambitious, nonspecific and completly useless.

Click to expand...

Heat pumps are getting better and better. However, ground source heat pumps work far better.
It isn’t always possible to retrofit a good GSHP system. But if it is built into the house from the start, it has very good results.

Our winters are a bit colder than yours. 10 below is not unusual and 20-30 below is not unheard of.
We have no wood stove, no natural gas, our heat is solely from the heat pump and resistance heat as a backup (which hasn’t been used so far).

In the event of a grid outage we have solar panels and batteries.

The trick with our house is it is extremely well insulated with as few “holes” in it as possible. No chimney, no exhaust for the clothes dryer, and all bath fans go through the ERV ventilation system to recover the heat before it is expelled.

Combined with a lot of thermal mass and using passive solar it is extremely efficient. We calculated we needed 19kW of solar to cover our annual energy needs (house and two cars). Turns out we needed about 11kW.

Zythryn said:

We calculated we needed 19kW of solar to cover our annual energy needs (house and two cars). Turns out we needed about 11kW.

Click to expand...

.
This is a part of your story I am not familiar with. Please tell more !

Always inspirational to follow what Zythryn is up to.

We looked into upgrading to a GSHP system, but was cost prohibitive for our existing home which would have required excavating already poured concrete, drilling deep vertical wells through a couple hundred feet of tough basalt, then re-pouring concrete. Would love to go this route in a future home if can get it done with new construction.

Good to have such an example from one of the most frigid climates in the continental US, showing heat pump tech is demonstrably effective and efficient. Certainly GSHP becomes more advantageous in more northern latitudes.

Since so much of a home's energy use in the U.S. comes from heating (more than cooling in most places), U.S. residents will have to ultimately ditch fossil fuels for heating in the near future if we hope to do our part in substantially mitigating climate change.

Over the last 12 months we have used about 14 MWh of electricity for our family of 4 in our 2550 ft^2 house. That includes all heat pump heating and cooling of air, heat pump heated water, both electric vehicles, induction stove, standard electric appliances including resistance heat clothes dryer, and pool pump. We might run the spa a bunch in the next 1.5 months before our annual true-up to use a bit of our ~2 MWh net excess generated electricity.