Electric Energy Usage

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stan1
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Re: Electric Energy Usage

Post by stan1 »

There's two factors: year round usage and seasonal spikes.

For year round you are still using 1600 KWH in Nov and 1900 KWH in Oct when I'd expect heat and AC to be minimized. What was your usage last spring when HVAC usage also would have been minimized? That indicates a lot of electricity is going to year round usage such as heated water and appliances that run regularly such as refrigerators and clothes dryers. How many refrigerators/freezers do you have and how old are they? Are you sorting clothes into the dryer by time to dry and air drying when possible? Hot water heater may be a good place to start if you are unable to take shorter showers, bathe young children together, etc.

Since heating and cooling are less than 1/3 of the bill in high usage winter and summer months I wouldn't start with your HVAC and insulation. I would expect to see much more seasonal spike in your climate in an all electric house.
Teague
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Re: Electric Energy Usage

Post by Teague »

First thing I'd do is install propane and switch to a propane water heater. We did just that 2 years ago, and it made a large difference in our energy costs. When they are plumbing that, make sure they leave a plugged tee near your clothes dryer, so you can easily switch that too if you want. And maybe an outlet for a gas stove in the future.
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SmileyFace
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Re: Electric Energy Usage

Post by SmileyFace »

MedicatedMoney wrote: Sat Dec 16, 2017 10:43 am we are using anywhere from 30-50% more energy from our neighbors. ....
Do your neighbors all have electric-based heat?
I find the comparisons I get somewhat comical. I have natural-gas heat so in the winter I an WAY more "efficient" than my neighbors - but in the summer - with my electric AC and swimming pool pump I am WAY less "efficient" than my neighbors. (It's the electric company that uses the term "efficient" in the statements they send - just because you use more or less of something than someone else does not determine efficiency - I work from a home office so am likely more energy efficient than some of my neighbors who use gas to commute and use electricity at an external office).
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Re: Electric Energy Usage

Post by Jack FFR1846 »

2800 square foot house with cathedral ceiling in all 2nd floor rooms. Oil forced hot air heat and hot water. Electric kitchen appliances and central air. Winter heat also provided by forced hot air wood furnace that runs in parallel with oil when I'm home to feed the beast.

Some numbers:
Oil delivered last week with discount $2.88 per gallon.
Electric rate 19.84 per kWHr, mainly provided by natural gas fired power plants at very high prices because of restricted delivery to New England.

Winter average month 700 kWHr
Summer average month 2000 kWHr

All lights are either CFL or LED.
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Wellfleet
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Re: Electric Energy Usage

Post by Wellfleet »

We are averaging 500 KwH in non-heating months.

It's a bit complicated in winter because we have an oil boiler and electric baseboard in the bedrooms with a minisplit for above freezing temp use.

We average 27 KwH on cold days or 800 kwH per month.

We are in Massachusetts.
jpdion
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Re: Electric Energy Usage

Post by jpdion »

squirm wrote: Tue Dec 19, 2017 8:57 am You're three times more than us but we have gas and located elsewhere. What's your rate? Given your situation and family size, it doesn't look too bad... But get an energy audit done.
Best advice -- get an energy audit done. Otherwise, you could end up with a misallocation of your efficiency investments.
Valuethinker
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Re: Electric Energy Usage

Post by Valuethinker »

stan1 wrote: Tue Dec 19, 2017 9:11 am There's two factors: year round usage and seasonal spikes.

For year round you are still using 1600 KWH in Nov and 1900 KWH in Oct when I'd expect heat and AC to be minimized. What was your usage last spring when HVAC usage also would have been minimized? That indicates a lot of electricity is going to year round usage such as heated water and appliances that run regularly such as refrigerators and clothes dryers. How many refrigerators/freezers do you have and how old are they? Are you sorting clothes into the dryer by time to dry and air drying when possible? Hot water heater may be a good place to start if you are unable to take shorter showers, bathe young children together, etc.

Since heating and cooling are less than 1/3 of the bill in high usage winter and summer months I wouldn't start with your HVAC and insulation. I would expect to see much more seasonal spike in your climate in an all electric house.
I agree there's something up in November and October.

One point which is sometimes missed is that air dryed clothes, indoors, burn roughly as much energy as an electric dryer-- laws of thermodynamics, depending where the dryer vents to.

If the heating system is HP and the electric dryer is not, then that's still a win. Say COP is 3.0x then only 1/3rd as much electricity. Gets more complex because of getting rid of humidity etc.

I agree check fridges but it's likely only to be an issue if they are pre 2000 (from memory, GWB further tightened the rules as of 2003) or even 1992. A 1985 fridge can burn 2000 kwhr pa, a 2016 one 550 kwhr pa.

I think a family with 4 children is not going to be able to save much on use of hot water. Baths for the kids, long showers for the teenagers. Teenagers develop budgeting habits when *they* pay the bills (I note this in myself) i.e. as adults-- not before; it's not worth having yet another reason to get ratty with your teenagers, when there are so many potential points of conflict ;-).

Thus, a Heat Pump water heater, if there is the space, is justified. Ditto a leak test.

I am presuming bulbs are LEDs or CFLs -- again, teenagers don't know that lights have an "off" switch ;-).

Older set top boxes and other electronics with instant on (again, I think GWB tightened the rules, as president) can be absolute kwhr hogs.
Valuethinker
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Re: Electric Energy Usage

Post by Valuethinker »

Teague wrote: Tue Dec 19, 2017 10:15 am First thing I'd do is install propane and switch to a propane water heater. We did just that 2 years ago, and it made a large difference in our energy costs. When they are plumbing that, make sure they leave a plugged tee near your clothes dryer, so you can easily switch that too if you want. And maybe an outlet for a gas stove in the future.
I think propane prices are quite variable depending where one lives? So it might not work so well for OP.
PFInterest
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Re: Electric Energy Usage

Post by PFInterest »

i stopped reading at heat set at 70, AC set to 72. seriously?
TareNeko
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Re: Electric Energy Usage

Post by TareNeko »

I would consider ductless heat-pump when the time comes to change your HVAC system. They are more efficient than forced-air type heat-pumps especially at lower temps. Also it is very easy to create zones with ductless system.
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AnimalCrackers
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Re: Electric Energy Usage

Post by AnimalCrackers »

ncbill wrote: Sun Dec 17, 2017 5:59 pm Home energy audit first - don't just think "insulation" - air sealing is critical (don't want to be heating unconditioned space like the attic)
+1

Why guess at the most cost-effective way to lower your energy bill, save the planet, etc?

Your power company or county or municipality may offer a rebate for much of the cost of the audit, like my utility did. And, if you have a contractor take action based on it, the contractor may credit you for the balance of the audit, like mine did.

I've had two such audits, and they were money well spent.

I suspect your first priority will be thorough air-sealing of all the ceiling penetrations, flue, etc., and then attic insulation. Air sealing is important and much, much easier before adding insulation. You may also want to Google "solar screens." I built ours and the hour a year I spend putting them up on our East- and West-facing windows has also made a significant difference in our summer utility bill.

https://www.energystar.gov/ia/partners/ ... y_2008.pdf
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Angelus359
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Re: Electric Energy Usage

Post by Angelus359 »

PFInterest wrote: Tue Dec 19, 2017 11:39 am i stopped reading at heat set at 70, AC set to 72. seriously?
I do 74 heat and 76ac

Am I better or worse
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RetiredAL
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Re: Electric Energy Usage

Post by RetiredAL »

MedicatedMoney

1. Neighbor or BH comparisons are useless. Too many variables including head count which equates to HW demand.
2. What is your cost of electricity?
3. What would you expect propane to cost?

As I said before, focus on HW. Just to give you some ideas.....

100,000 btu at 100% efficiency = 240 gallons from 50 degrees ( ground temp ) to 100 degrees. @ 4gpm in a shower, that's 60 minutes of shower time. At 2gpm, that's 120 minutes.

I'm in Corrupta-Fornia where electricity rates are inverted, the more you use, the higher the rate. My top tier rate is $.28/kwh. We have a mountain home100% electric and in summer when there is no heat, if there 6 people are there for a weekend, I expect 200 kwh of usage with 85% of that being HW. No HW HP. For the cabin,100,000 btu of HW heat costs $8.32. Since the # weekends a year is low, it does not pay to change it to propane. Winter heat is mostly wood stove when occupied, but electric at 45 degrees set-point when empty.

Here at my prime residence, using NG, that 100,000 btu into HW costs me only $1.76 ( 75% eff tank heater )

My daughter, who lives in Montana, pays only $.10/kwh and between $.75 (summer) and $2.00 (winter) per gallon of propane. @ $2.00/gal, so her HW ( tank-less 90% eff. ) costs about $2.77 for 100,000 btu.

So before you even invite an Energy Auditor in, do some footwork so you can understand the relativeness of what he says. Go measure your shower flows, estimate the minutes, measure gallons in a bath, ect. You can't change how much water the dishwater uses per load, so you can change how often it runs. The key is to understand where to focus, what give you the best bang for the buck. Think of this like BH's think of investing cost.

Also factor that most households are not 6 people, thus any "typical" will be off in your case, just like when you compare to neighbors or your electric bill uses the term "similar houses in you area".

Someone said they liked a Delta Shower Head that used on 1.5 gpm. If you find yours are older 4 gpm heads, well there is a huge savings for only a few $ outlay. You can get heads with under 1 gpm.

Lastly, since you already have your Dec bill, your billing cycle is early in the month, thus your Oct and Nov bills more than likely represent usage in Sept and Oct, when I would expect you have little heating or cooling demand. That may give you a lead on your usage for other than Heating or Cooling.
Teague
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Re: Electric Energy Usage

Post by Teague »

Valuethinker wrote: Tue Dec 19, 2017 11:29 am
Teague wrote: Tue Dec 19, 2017 10:15 am First thing I'd do is install propane and switch to a propane water heater. We did just that 2 years ago, and it made a large difference in our energy costs. When they are plumbing that, make sure they leave a plugged tee near your clothes dryer, so you can easily switch that too if you want. And maybe an outlet for a gas stove in the future.
I think propane prices are quite variable depending where one lives? So it might not work so well for OP.
True, and variable depending on the season as well (cheapest Summer and Fall, typically.) But propane is much cheaper than several years ago and likely to remain cheap due to fracking and such.

I learned something interesting a couple of years ago - propane is actually a byproduct. No one sets out to extract propane for its own sake. It is a byproduct of natural gas production and petroleum refining. It is the supply and demand from those industries that drives the price of propane. We residential consumers are just along for the ride.
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Re: Electric Energy Usage

Post by Valuethinker »

Teague wrote: Wed Dec 20, 2017 8:23 am
Valuethinker wrote: Tue Dec 19, 2017 11:29 am
Teague wrote: Tue Dec 19, 2017 10:15 am First thing I'd do is install propane and switch to a propane water heater. We did just that 2 years ago, and it made a large difference in our energy costs. When they are plumbing that, make sure they leave a plugged tee near your clothes dryer, so you can easily switch that too if you want. And maybe an outlet for a gas stove in the future.
I think propane prices are quite variable depending where one lives? So it might not work so well for OP.
True, and variable depending on the season as well (cheapest Summer and Fall, typically.) But propane is much cheaper than several years ago and likely to remain cheap due to fracking and such.

I learned something interesting a couple of years ago - propane is actually a byproduct. No one sets out to extract propane for its own sake. It is a byproduct of natural gas production and petroleum refining. It is the supply and demand from those industries that drives the price of propane. We residential consumers are just along for the ride.
https://www.eia.gov/petroleum/weekly/propane.php

looks like range is about $1/ gal

Central Atlantic maybe 70 c/ gall above national average of $2.46 (so around 25% of total price).

Like you, I vaguely knew that, that propane is an extract from other production.
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Sandtrap
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Re: Electric Energy Usage

Post by Sandtrap »

$100 electric/mo
$150 gas (heat)/mo
Averages per year.
Approx. 5000 sf. 3 story.
Temperature variation over the year. 12 - 90 degrees.
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pshonore
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Re: Electric Energy Usage

Post by pshonore »

Valuethinker wrote: Wed Dec 20, 2017 12:12 pm
Teague wrote: Wed Dec 20, 2017 8:23 am
Valuethinker wrote: Tue Dec 19, 2017 11:29 am
Teague wrote: Tue Dec 19, 2017 10:15 am First thing I'd do is install propane and switch to a propane water heater. We did just that 2 years ago, and it made a large difference in our energy costs. When they are plumbing that, make sure they leave a plugged tee near your clothes dryer, so you can easily switch that too if you want. And maybe an outlet for a gas stove in the future.
I think propane prices are quite variable depending where one lives? So it might not work so well for OP.
True, and variable depending on the season as well (cheapest Summer and Fall, typically.) But propane is much cheaper than several years ago and likely to remain cheap due to fracking and such.

I learned something interesting a couple of years ago - propane is actually a byproduct. No one sets out to extract propane for its own sake. It is a byproduct of natural gas production and petroleum refining. It is the supply and demand from those industries that drives the price of propane. We residential consumers are just along for the ride.
https://www.eia.gov/petroleum/weekly/propane.php

looks like range is about $1/ gal

Central Atlantic maybe 70 c/ gall above national average of $2.46 (so around 25% of total price).

Like you, I vaguely knew that, that propane is an extract from other production.
Propane, Butane and Ethane are byproducts known as NGLs (natural gas liquids). They occur naturally in some wells that produce "wet" gas and AFAIK they have to be separated out before it goes in the pipeline. I believe a gallon of Propane contains 91000 BTUs of energy (compared to 140000 BTUs in a gallon of heating oil so heating oil is usually a more economical way to heat your house). The other problem (at least in New England) is who owns the tank? With heating oil, the homeowner almost always does and therefore can buy from anyone. Underground propane tanks are expensive to install and some are owned by the installing company meaning you're locked to them for supply. Heating oil in New England is roughly $2.50/gallon.
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telemark
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Re: Electric Energy Usage

Post by telemark »

Valuethinker wrote: Tue Dec 19, 2017 11:28 am One point which is sometimes missed is that air dryed clothes, indoors, burn roughly as much energy as an electric dryer-- laws of thermodynamics, depending where the dryer vents to.
I would question that. The amount of heat consumed by air drying should be very close to the amount actually needed for drying, converting the water in the clothes to water vapor. The electric dryers I've observed (admittedly a small number) all seem to use a great deal more heat than that, in the interest of faster drying. So there is an efficiency gap. And the ones I've seen all vent directly to the outdoors. I suppose it would be possible to direct the exhaust through a heat exchanger, to keep the heat indoors during the times of the year when you would want to do that, but as far as I know nobody does that.
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Re: Electric Energy Usage

Post by Valuethinker »

telemark wrote: Wed Dec 20, 2017 3:01 pm
Valuethinker wrote: Tue Dec 19, 2017 11:28 am One point which is sometimes missed is that air dryed clothes, indoors, burn roughly as much energy as an electric dryer-- laws of thermodynamics, depending where the dryer vents to.
I would question that. The amount of heat consumed by air drying should be very close to the amount actually needed for drying, converting the water in the clothes to water vapor. The electric dryers I've observed (admittedly a small number) all seem to use a great deal more heat than that, in the interest of faster drying.
OK but where then does that heat go? IF they both vent to the same space, the total amount of heat is the same, whether you dry your clothes quickly in a dryer or overnight in a spare room?

Even the mechanical operation of the dryer will produce heat, so that energy does get released back into the house?
So there is an efficiency gap. And the ones I've seen all vent directly to the outdoors. I suppose it would be possible to direct the exhaust through a heat exchanger, to keep the heat indoors during the times of the year when you would want to do that, but as far as I know nobody does that.

In Europe, condenser dryers are popular. They have a cassette which fills up with hot, condensed, water. You then empty that down the drain-- but a lot of that heat would in fact vaporize back into the house air.
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telemark
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Re: Electric Energy Usage

Post by telemark »

Valuethinker wrote: Wed Dec 20, 2017 4:50 pm OK but where then does that heat go? IF they both vent to the same space, the total amount of heat is the same, whether you dry your clothes quickly in a dryer or overnight in a spare room?
Some of the heat is absorbed by a phase change, liquid water into water vapor. This is the same amount whichever method is used, and in the case of a cold room, it would need to be replenished by heating the room. But in the case of the dryer, more heat goes into raising the temperature of the air inside the dryer, raising the temperature of the clothes themselves, raising the temperature of the dryer (they get warm to the touch), radiating heat into the surrounding room, etc. All of this is essentially waste heat in that it isn't necessary to dry the clothes, although in some cases it may be useful to heat the room. In other cases it may just make more work for the air conditioner.

The total amount of heat is not the same: your premise is just wrong. Energy is always conserved, heat is not.
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just frank
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Re: Electric Energy Usage

Post by just frank »

telemark wrote: Wed Dec 20, 2017 5:14 pm
Valuethinker wrote: Wed Dec 20, 2017 4:50 pm OK but where then does that heat go? IF they both vent to the same space, the total amount of heat is the same, whether you dry your clothes quickly in a dryer or overnight in a spare room?
Some of the heat is absorbed by a phase change, liquid water into water vapor. This is the same amount whichever method is used, and in the case of a cold room, it would need to be replenished by heating the room. But in the case of the dryer, more heat goes into raising the temperature of the air inside the dryer, raising the temperature of the clothes themselves, raising the temperature of the dryer (they get warm to the touch), radiating heat into the surrounding room, etc. All of this is essentially waste heat in that it isn't necessary to dry the clothes, although in some cases it may be useful to heat the room. In other cases it may just make more work for the air conditioner.

The total amount of heat is not the same: your premise is just wrong. Energy is always conserved, heat is not.
Agree with telemark here. The latent heat required to dry the clothes comes from the central heating system in the air dry case, and the dryer in the dryer case. Your space heat BTUs are usually cheaper than electric resistance (bar) BTUs, so air drying is cheaper. The dryer also blows conditioned air outside, pulling unconditioned air into the house at a rate of 200 cfm or so, incurring another several thousand BTU/hr (or a kW or two) penalty in the winter.
denovo
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Re: Electric Energy Usage

Post by denovo »

stats99 wrote: Sat Dec 16, 2017 10:53 am
Winter temp set at 62 Night
Wow. That seems rough to me.
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Wakefield1
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Re: Electric Energy Usage

Post by Wakefield1 »

adamthesmythe wrote: Sat Dec 16, 2017 12:50 pm Heat pump and Pennsylvania don't go together.

Propane? Oil?
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Valuethinker
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Re: Electric Energy Usage

Post by Valuethinker »

telemark wrote: Wed Dec 20, 2017 5:14 pm
Valuethinker wrote: Wed Dec 20, 2017 4:50 pm OK but where then does that heat go? IF they both vent to the same space, the total amount of heat is the same, whether you dry your clothes quickly in a dryer or overnight in a spare room?
Some of the heat is absorbed by a phase change, liquid water into water vapor. This is the same amount whichever method is used, and in the case of a cold room, it would need to be replenished by heating the room. But in the case of the dryer, more heat goes into raising the temperature of the air inside the dryer, raising the temperature of the clothes themselves, raising the temperature of the dryer (they get warm to the touch), radiating heat into the surrounding room, etc. All of this is essentially waste heat in that it isn't necessary to dry the clothes, although in some cases it may be useful to heat the room. In other cases it may just make more work for the air conditioner.
Thank you.

I can see then where my misconception lay (I never took university-level physics, and my high school physics was taught by someone who should not have been given that role).
The total amount of heat is not the same: your premise is just wrong. Energy is always conserved, heat is not.
See above. I knew that (energy conservation) but didn't think it through.
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Re: Electric Energy Usage

Post by Valuethinker »

denovo wrote: Wed Dec 20, 2017 6:29 pm
stats99 wrote: Sat Dec 16, 2017 10:53 am
Winter temp set at 62 Night
Wow. That seems rough to me.
There are habits in these things. I know people who can't sleep in any warmer, and some who freeze below high 60s.

It has been studied and the old saws are true. Men like office temperature around 21 degrees C (70F) and women like it around 25 degrees C (9 degrees F warmer). Partly that is office clothing (suits are warmer) but it's also to do with how the 2 genders perceive cold-- even then, there is a wide range of individual preferences.
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Re: Electric Energy Usage

Post by Valuethinker »

just frank wrote: Wed Dec 20, 2017 5:50 pm
telemark wrote: Wed Dec 20, 2017 5:14 pm
Valuethinker wrote: Wed Dec 20, 2017 4:50 pm OK but where then does that heat go? IF they both vent to the same space, the total amount of heat is the same, whether you dry your clothes quickly in a dryer or overnight in a spare room?
Some of the heat is absorbed by a phase change, liquid water into water vapor. This is the same amount whichever method is used, and in the case of a cold room, it would need to be replenished by heating the room. But in the case of the dryer, more heat goes into raising the temperature of the air inside the dryer, raising the temperature of the clothes themselves, raising the temperature of the dryer (they get warm to the touch), radiating heat into the surrounding room, etc. All of this is essentially waste heat in that it isn't necessary to dry the clothes, although in some cases it may be useful to heat the room. In other cases it may just make more work for the air conditioner.

The total amount of heat is not the same: your premise is just wrong. Energy is always conserved, heat is not.
Agree with telemark here. The latent heat required to dry the clothes comes from the central heating system in the air dry case, and the dryer in the dryer case. Your space heat BTUs are usually cheaper than electric resistance (bar) BTUs, so air drying is cheaper.
Thank you both for your explanations.
The dryer also blows conditioned air outside, pulling unconditioned air into the house at a rate of 200 cfm or so, incurring another several thousand BTU/hr (or a kW or two) penalty in the winter.
Yes that air change factor could be the most significant problem. Also drafts make us feel colder, which behaviourally tends to mean we push up the thermostat. I have never been in a Passivhaus (Passive House) but the feeling of no cold air movements must be quite strange.
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Re: Electric Energy Usage

Post by Wakefield1 »

Would an air to air heat exchanger have any potential for saving energy or heat in a case of needing to have air exchange such as replacing the air lost as exhaust from a dryer or even the draft air up the flue from a furnace? (Lost air causes air from outside the house to come in somewhere)
if the flue or dryer exhaust went out through a heat exchanger some of its useful heat could be added to outside air coming in
(assuming winter heating season,not summer air conditioning)
BerkeleyChris
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Re: Electric Energy Usage

Post by BerkeleyChris »

Here is my monthly energy use and actual bills for 2017. 1 person in 1200 square feet

2017-01-18 205 kWh $25.48
2017-02-16 157 kWh $19.84
2017-03-20 213 kWh $29.43
2017-04-19 164 kWh $23.82
2017-05-18 130 kWh $18.87
2017-06-19 186 kWh $26.99
2017-07-19 205 kWh $29.75
2017-08-18 181 kWh $26.25
2017-09-19 231 kWh $33.51
2017-10-18 178 kWh $25.82
2017-11-16 202 kWh $29.32
2017-12-18 261 kWh $37.86
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just frank
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Re: Electric Energy Usage

Post by just frank »

Wakefield1 wrote: Thu Dec 21, 2017 9:55 pm Would an air to air heat exchanger have any potential for saving energy or heat in a case of needing to have air exchange such as replacing the air lost as exhaust from a dryer or even the draft air up the flue from a furnace? (Lost air causes air from outside the house to come in somewhere)
if the flue or dryer exhaust went out through a heat exchanger some of its useful heat could be added to outside air coming in
(assuming winter heating season,not summer air conditioning)
IN the dryer case, you would end up getting condensation or icing, not to mention lint, in the heat exchanger. This would require a defrost controller and frequent cleaning....and most people would not go for the cost/benefit...so they don't exist. You CAN get a **condensing or HP dryer** and achieve the same effect (no outside vent required) they are just rather expensive and slow, and have not taken off in the US. Lots of 'frugal' people just vent their dryers indoors in the winter...but this is a bad idea given the high humidity (that mostly ends up condensing in your cold attic and molding out your roof decking) and lint and dryer sheet stuff that gets into your indoor air.

With a combustion appliance, feeding them outside air is becoming increasingly popular, but it is not more efficient....the unconditioned air cools the flame by precisely the same amount as the extra heat required by pulling in an equal amount of unconditioned air in through cracks all over the house. But units with forced airflow (as opposed to natural draft like a chimney) tend to run more consistently and if fed outside air will do so even if the house is depressurized (e.g. by a large kitchen vent).

The opportunity here is the heat in the air stream going up the chimney. Most units are **intentionally** designed to keep that air warm enough to be above the dewpoint of the exhaust (burning hydrocarbons makes H2O)....don't want condensation in the chimney running onto your basement floor making a puddle. Also, if your heat exchanger is condensing it is wet and will corrode much faster than if it is hot and DRY. The opportunity here is to get a **condensing furnace** which has both a corrosion proof heat exchanger AND a means of collecting and pumping away condensation....and maybe 10-15% higher fuel efficiency. These cost more, have condensate pumps that can fail/clog, but have simpler/cheaper exhaust requirements...like a PVC pipe out the wall rather than a chimney.

TL;DR:
As with all things, there is a cost-benefit calculation to be done here....condensing dryers and furnaces are not slam-dunks, but you should look into them and figure out if they work for you when replacing outdated equipment. Most houses have much better payback items that go unaddressed, like airsealing, than can be found by a simple energy audit.
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Re: Electric Energy Usage

Post by Matt Y. »

Heat pumps in PA climate - even the newer more efficient units - are a poor efficiency match.

Propane fireplace insert with blowers are very inefficient - would suggest a pellet stove for that kind of initial investment for much more heat/ cost.
marklar13
Posts: 123
Joined: Wed Jul 08, 2015 11:47 am

Re: Electric Energy Usage

Post by marklar13 »

3000 sqft house, just built last year.

Electric oven (gas range), dryer, A/C, well-pump, fridge, dishwasher, occasionally 2nd freezer if primary overflows. Propane heat and hot water. I set the A/C to kick on at 78. Also, I work from home so in theory that should skew things up slightly. Last 7 months looks like most months we are btwn 500 and 600 before A/C usage:

Jun: 675 kWh
Jul: 719 kWh
Aug: 729 kWh
Sep: 644 kWh
Oct: 679 kWh
Nov: 537 kWh
Dec: 597 kWh
dpals
Posts: 1
Joined: Fri Dec 22, 2017 2:10 pm

Re: Electric Energy Usage

Post by dpals »

Medicated Money - we are almost twins.

Family of 5, SE PA, ~2400 sq ft, all electric house (heat pump and mini-splits for heating and cooling, electric HW, dryer, etc....). Our thermostats are set to ~71 year round.

Our recent monthly use is fairly close to yours:

December: 2315
November: 1356
October: 1493
September: 1453
August: 1499
July: 1263

We've lived in our house ~20 yrs and have converted from oil for heating / hot water to electric air-sourced heat pumps and traditional electric hot water (no HW HP).

Here are my thoughts from reading the comments on this post:

1. Financially, it has been a net positive switching from oil to heat pumps. Overall, we are spending less for electricity now than we spent for combined oil + electricity in the past (and we didn't have central air conditioning before). This would be even more true if oil prices had remained as high as they were several years ago. Personally, I don't have any plans to change to propane (gas is not available for us) because of the need for an tank (ugly!) and I'm happy that we aren't impacted by fluctuating prices and delivery.

2. I agree with the comments about air sealing and adding insulation. Especially with an ~50yr old house like mine, there was a lot I had to do to tighten things up. It wasn't all that costly but did take some work which has paid off well.

3. Make sure you a) shop for electricity and b) are setup to use the Residential Heat (RH) plan @ PECO. I just switched to a generation provider with a fixed rate of $0.0599 / kwH through December of 2019 and the RH plan saves another few cents per kWh on PECO's distribution charges during the winter.

3. PECO's website has some great tools for viewing your monthly / daily usage and has a nice overlay showing the temperature. You can also download your detailed usage data (down to the hour) for your own analysis (yes, I'm a nerd and have done that :D )

All in all, I''m happy with our cost / comfort / convenience. Would be happy to discuss further - I guess you could say it has been a hobby of mine to get our house to where it is today.
tj
Posts: 3986
Joined: Thu Dec 24, 2009 12:10 am

Re: Electric Energy Usage

Post by tj »

I have 720 sq ft in PHX. Gas water heater and furnace. Electric oven. No dishwasher or laundry.

07/03 - 568 kWh
08/03- 622 kWh
09/03 - 562 kWh
10/03 - 322 kWh
11/03 - 178 kWh
12/03 - 68 kWh

Summer A/C is kept at 78. 85 when out of the apartment.

Gas is $18 but has gone up to $25ish in winter with some use of the furnace.
Auream
Posts: 505
Joined: Thu Mar 20, 2008 1:07 pm
Location: Raleigh, NC

Re: Electric Energy Usage

Post by Auream »

The people suggesting a switch to propane are either misinformed or bad at math. Its trivially easy to do the math and see that even at current propane prices, which are lower than they were a few years ago, an electric heat pump is going to be cheaper as long as the COP is 1.3 or higher, which should be easily achievable by even an old heat pump (unless your heat pump is really old or not working correctly, in which case you should replace it with a new, higher efficiency unit). The tipping point will of course shift depending on your exact cost of electricity and propane. If your electricity cost is much higher than the national average, youi'll still come out ahead with a heat pump but not by as much.

Here's the math, using national average prices for propane and electricity, per 100,000 BTU:
Propane: 100,000 * 2.489/gallon (national average) / (91,000 BTU/gallon * 0.92 efficiency (middle of the road propane furnace)) = $2.97/100kBTU
Heat Pump: 100,000 * 0.1284/kwh (national average) / (3412.14btu/kwh * 2.8 COP (middle of the road heat pump seasonal average COP)) = $1.34/100kBTU

So less than half the cost per unit of heat as a 92% efficient propane furnace. If you have a better than middle of the road heat pump (which almost all brand new ones would be) or your electricity costs are lower than the national average (mine are closer to 11cents per KWh), you come out even further ahead. So don't even consider going propane unless your electricity is REALLY expensive!

EDIT: Fixed incorrect typing out of the equations as noted by Epsilon Delta.
gretah
Posts: 244
Joined: Wed Apr 20, 2016 11:14 pm

Re: Electric Energy Usage

Post by gretah »

Put water heater on a timer. It only takes 2 hours or less to heat water in a large water heater. Set the timer to turn on the water heater at 4am and 4pm. Set it to turn off at 10pm or midnight and 9am. Experiment.

Your dishwasher probably has a water heater built in so using cool water won't make a difference. Start the dishwasher at bedtime. Try it.

In my town, today's temps were high 34F and low 28F. I turn off the heat at night. As another poster recommended, use a down comforter.

Heat the body, not the room. As others have suggested, I wear layers at home including a hoodie or a cap. And I keep a heating pad set to low under my feet. I then transfer it to my lower back in bed. Heating pads last far longer than electric blankets.

Use a knit hat! Lots of heat loss is from the head. I sleep in a knit cap. Makes a huge difference. I wear one at home.

Drink lots of hot tea and apple juice.

Put your clothes in the dryer for 5-10 minutes before you change clothes for work or home or bed. Putting on warm clothes makes a huge difference in staying warm.

If you want to use a space heater, use an oil-filled radiator one and place it close to you. Heat your area, not the room.
finite_difference
Posts: 2347
Joined: Thu Jul 09, 2015 7:00 pm

Re: Electric Energy Usage

Post by finite_difference »

TylerDavis wrote: Sat Dec 16, 2017 4:42 pm Those of you claiming that "heat pumps don't work in PA" are referring to woefully outdated information. They absolutely work, and at much colder climates than that. They have > 1 COP down to 10 or 20 degrees below zero.

https://energy.gov/eere/buildings/artic ... arm-winter

https://en.wikipedia.org/wiki/Air_source_heat_pumps

My parents live in Reading PA and have had a heat pump for 30 years. Electric bills never above $200 a month.

That the OP stsated "compressor runs constantly" tells me the heat pump is either under-sized, or leaking freon, or the house has no insulation. An HVAC service call and/or home energy audit should clear this up.
I think you’re right, but you need a good heat pump that is designed to be efficient at low temperatures. And then try to turn the house temp down and supplement with a new, advanced and safe ceramic space heater for e.g. the baby’s room.

I dislike being cold at home, and like to keep the thermostat at around 73, but I can tolerate keeping it at around 78 in the summer time.

Weather strip and caulk/winterize all windows and doors.

Replace every single light with LED (CFL is ok if already installed.)

Insulate the attic.

For the water heater, check that it’s not set too high. You can use the stove to boil water :)

Starting around 2001 (if energy star rated), refrigerators became a lot more efficient. If yours is more than 17 years old consider replacing it.
The most precious gift we can offer anyone is our attention. - Thich Nhat Hanh
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snackdog
Posts: 980
Joined: Wed Nov 12, 2014 4:57 am

Re: Electric Energy Usage

Post by snackdog »

Good luck finding a statistical sampling of nearby residents with comparable size house, household and utility setup here on BH. Not sure why you don't trust the comps from your utility provider as they have all the data.

Average family usage in PA is under 1000 khw/month so you are definitely way high. I suggest having someone come do an energy audit. You need to find out where it is all going.
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