Questions tagged [energy-efficiency]
Questions about ways to measure and improve the ability to get useful work out of devices that consume energy. This includes coal, oil and gas as well as electricity.
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How do I tackle insulating rim joists with brick in a partially finished basement
I have done a fair bit of research on this, but still left with a dilemma. Here's some basics:
1920s single level, brick built home (see photos linked below). Exterior brick is painted.
located in ...
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Energy efficient home improvement tax credit
I have been doing some reading for the tax credits available for furnace and heat pump installations.
https://www.irs.gov/credits-deductions/home-energy-tax-credits
and
https://www.energystar.gov/...
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How can I heat up my apartment more efficiently?
I live in a studio apartment that I rent from my parents, in France. Each winter, it gets very cold. The region is very sunny, but the specific area around my building is significantly colder (due to ...
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HPWH better to raise temperature or use high demand mode
I have a hybrid heat pump water heater (compressor plus resistance heating elements).
I'm going to have company over for a week so 6 people, instead of 2. Is it better to increase the tank temperature ...
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How best to air seal kitchen pantry ceiling
We just moved in and had an energy audit done by a professional, and they flagged that we were losing a ton of air through the ceiling in our kitchen pantry/ closet. The ceiling itself is a weird ...
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Insulating back of wall from attic space
I have a 3rd floor area with a crawl space all around it with some failing 2x4 bats of insulation, the critters and age have it rolling off the back side of the walls. I was just going to place the ...
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Heat Pump Air Exchanger efficiency gains in Snow/Cold
I have a 5 ton Bosch air to air heat pump, just installed last fall. I built a small timber framed cover to protect it from snow. One thing I was hoping to also do was to cover the sides of the small ...
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How to Airseal and Insulate Texas Homes
I am interested in what I can do to help improve the energy efficiency of older Texas homes.
I am looking to purchase one in the new year but it is my understanding that in 2012 the energy efficiency ...
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What is the difference in efficiency between upflow and downflow furnaces?
I have been doing a bit of research on HVAC systems, and recently learned about upflow vs downflow configurations, and understand that upflow is supposed to be more efficient for heating and downflow ...
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Does an air conditioner's fan use more power on Max than on Auto?
I have an inverter air conditioner unit. I usually set it on 26°C, to save energy consumption. I live in a really hot area (it's 34°C right now (~93°F), in the middle of the night). My questions is ...
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Fixed vertical space over concrete suspended floor - how to allocate between insulation depth vs. screed depth?
I have an extension being built on usual concrete beam & dense block over a ventilated void. The external extension area is 3 x 6m. Ventilation is via two 215x65 plastic airbricks and telescopic ...
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Separate furnace energy usage from other appliances?
I am looking to reduce my utility bills. It only makes sense if I know what my current energy usage (natural gas, electricity, etc) is for a given applicance (furnace, water heater, etc) before ...
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Leaving second floor window open while running central AC [closed]
We know that windows should be closed while running the AC, but since the central AC and thermostat of my house is on the first floor, I was wondering whether leaving the window open decreases the ...
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Why would water faucets use a different energy source from the radiators?
In my apartment, hot water in the faucet is heated by an electric heater, while the hot water in the radiators for heating the rooms comes from a central gas boiler in the building. To me it seems ...
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Is high standby power consumption of heat pump water heater normal and how to reduce?
I recently got my very well working tankless gas water heater replaced by a Rheem ProTerra 50gal HPWH.
I feel the water heater consistently draws way too much power (I measure with CT clamps). ...
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Criteria for Energy Star energy estimates of heat pump water heater
Every heating appliance in the US features an "Energy Guide" label stating "typical" usage. In my case, the Heat Pump Water Heater states an estimated yearly energy use of 837kWh.
...
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How can I insulate the sloped ceiling of an attic room?
We have a century home. First two floors do well in summer / winter, 3rd floor is always too hot or too cold. The attic was completely uninsulated.
The plan was to use batt insulation on the attic ...
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How to make this pulley system more efficient?
I am trying to make a portable pulley system to lift heavy stuff. I made the following prototype using 8 individual pulleys:
When I pull the rope, the load should seem approximately 8 times lighter ...
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Plugging refrigerator only when necessary? (bottled beers)
I have a small and cheap refrigerator that I use to store beers. It has a small freezer that is of no use to me.
I am only using this refrigerator 5 times a year (during "events"), and I ...
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Proportional circulation pump control - possible for "simple" pumps?
Thinking of implementing proportional pump control to raise efficiency in our hot water based heating system.
Proper proportional control is possible using PWM control in high quality pumps like the ...
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Why does bleeding radiators save energy?
I wanted to bleed my radiators by myself for the first time and I was wondering what is the reason that bleeding radiators saves energy?
Most of the guides on bleeding radiators mention that this is ...
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Real world difference between a 0.18 W/m^2k U-value and 0.22 W/m^2k U-value
I'm currently choosing the thickness of the PIR insulation I will use for the ground floor (first floor US) in my house. It's a traditional (UK) suspended timber floor build with concrete foundations ...
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Why would a particular heat pump model be illegal in my state?
I am trying to replace an electricity-hungry whole-house electric furnace with something that will be more cost-effective. I live in a high-altitude part of New Mexico, where I don't need to use much ...
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Is there more to consider than the R-value when installing stucco in the Southwest?
I live in the Southwest and notice 90% of the homes in my area are stucco. Since I'm considering wrapping the house in an additional layer of insulation, then new siding, I am considering stucco.
Many ...
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Are new aircons with less BTUs more efficient than the older ones?
I am trying to replace the air conditioning device at home but I am not sure how to compare my old Panasonic that was bought in 1999 (possibly model of 1997 or 1998). Some facts:
I was not able to ...
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Should the door be open or closed between two separate HVAC systems?
We recently built out an additional 600sqft theater room in our attic. It’s a big room with 14’ high vaulted ceiling. We live in Houston and room heat load is fairly high. We installed a 2-ton unit ...
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Why are so many radiators installed beneath a window (at least in Germany)?
I live in Germany and I always wondered why the radiators in most apartments are installed right beneath a window. The pictures below show an example (this is an older building, but you see similar ...
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Home energy monitoring in split floor with one compressor
I have an odd situation where I live on a floor split in two and I want to split the electricity bill fairly with my floormate. I am looking at the home energy monitoring systems that have all the ...
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increasing R-value for old vaulted ceiling
I have vaulted ceilings in the main living space. Internally there are 2x6 joists between the roof and the drywall and the insulation I am guessing is original from the 1960's so this section of roof ...
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Is it more efficient to heat a room using an air conditioner (heat pump) when the windows are open?
In general, using an air-conditioner for heating is more efficient than a standard electric heater or radiator. But in our home, we keep the windows open all the time, in order to decrease the chance ...
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Why is my house energy efficient only in winter?
My electric utility company sent me a graph of my home's electricity usage over time as shown in the picture below. My home beats what the company considers as efficient homes in the neighborhood when ...
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Using water cooler for CNC laser as residential heat pump
I want to save money on heating bills. Residential heat pump systems cost thousands of dollars, which I can't afford. I am considering using a heat pump marketed to chill water for cooling CNC lasers (...
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Where can I find the efficiency of my heat pump with respect to temperature?
I can heat my house either with a standard gas heater, with a documented efficiency of 0.9, or with an heat pump, with a standardized coefficient of performance (Seasonal Coefficient of Performance) ...
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(When) Does room messiness affect water heater efficiency?
I have what I think of as a "standard US electric standby water heater." I will update this when I know the model; I am out of town right now.
It is located in a cold, cluttered closet in a ...
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Most efficient heating system @ ~41° N
I'm researching building a home on a property I just bought. Water is plentiful but there is little or no chance of getting municipal services such as natural gas or electricity. However I have open ...
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How do the old and new (post-2021) EU energy labels for LED light bulbs compare?
One of my light bulbs recently failed, for the first time in a few years, and I had to go buy a replacement. Usually I try to look for the ones with the best EU energy label rating, since not only do ...
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If I live in the US Southwest, would a heat pump or conventional dryer use less energy?
Suppose I live in Poway, CA (weather), where temperatures are roughly between 50 and 90 F throughout the year and relative humidity is generally between 40 and 60%. With climate change the highs have ...
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What is the optimal number of solar panels for my house?
Just had a solar power tech stop by. With the orientation of our house and the solar load, our property (house + workshop) can support roughly 41 panels. Each panel provides 370 W (max)...which ...
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120v vs 240v Mini Split Efficiency
I am under the impression that, as a general rule, 110v heating and cooling options are inherently not very efficient. So I was surprised to find a 120v mini split shopping around with a fairly decent ...
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Is there a low-e alternative to double-pane gas-filled window panes?
I spoke with a local glass retailer and he said instead of using double-pane gas filled windows, I could instead use a 3-layer sandwich of, say, 1/8", 1/4", 1/8" panes to achieve the ...
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How to find electric device(s) driving a high electric bill?
The cabin electric bill came and I gave it what I thought would be a cursory glance and it looked unusually high. Not just for this cabin, but in my experience with our houses. Our main house is a ...
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Why is Condenser energy guide rating different from advertised?
I'm installing a Carrier 24APB6 which has advertised up to 17 SEER. The seller tells me it is a 16 SEER unit but the yellow Energy Guide sticker on the condenser gives it a SEER rating of 14 on a 13-...
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Can I gain AC efficiency by spraying condensate water on the outdoor coils?
Recently, I was working from the basement and I noticed tonnes of condensate water going down the drain, and thought I might re-use it to improve the efficiency of my home AC system.
So I put a ...
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same-sized alternatives to F14T12 bulb
I have two bathroom light fixtures with very old magnetic ballasts and F14T12 fluorescent bulbs. These are, of course, a 1.5-inch diameter. I've been doing some bathroom renovations and I thought this ...
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Do smart or programmable thermostats actually save money?
I am looking at replacing all the thermostats in my house. I have hot water baseboard heat and forced air A/C. Each room's baseboard heat is controlled by a thermostat in that room.
I tend to prefer ...
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How can heat pump water heaters be more efficient when they just use heat from heated space? [duplicate]
I understand the principle of heat pumps, and it makes sense that a heat pump / AC split system is more efficient then for example resistive heating for heating a house. In this case, the heat pump ...
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How could I insulate a thin hot roof and bring it to current Southern CA code?
So we started an exterior remodel today, and found that our roof construction is way more mickey mouse than I thought it was.
Our house has vaulted 2nd floor ceilings through most of the 2nd floor ...
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Is there any considerable advantage to a forced air-to-air heat exchanger over just cleverly positioned positive pressure forced air intake?
This is from a typical North Western European housing perspective where most (older) buildings will not have forced air/AC/heat pumps etc. for various reasons, and most houses are only heated using ...
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Replacing 2 hot water heaters with 1
I've recently purchased a home that has two hot water heaters - one at each end of the house. One in the garage, one in a closet. They're both showing their age, and both cost quite a bit to operate. ...
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Determine highest "carbon reduced per dollar spent" option for reducing pollution generated by home?
I've been talking with friends and coworkers about how I can reduce the amount of pollution generated by my house (heating the air, heating the water, cooking the food, etc.) Everybody has a ...
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