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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2
votes
2answers
79 views

How can I power multiple raspberry pi around the house?

I am planning to power multiple Raspberry Pi's around the house. Some will be security cameras, one will be a media player connected to TV and another one will manage home network and maybe a website ...
2
votes
1answer
82 views

How can 12 V halogen downlights be much more efficient than 220 V ones?

The house I bought has halogen downlights pretty much everywhere, and they are all 12 V. I was wondering why bother with stepping down to 12 V but didn't think much about it. When looking at ...
-1
votes
0answers
26 views

What is the most energy efficient strategy for using my A/C unit?

I recently installed a 12,000 BTU Mini-Split A/C unit with an inverter - http://www.tempstar.com/products/dfac.html I was told that it uses approximately 0.6Kw/hour. What I am really curious about ...
1
vote
1answer
59 views

Close Garage Door?

My wife insists the garage should be closed in the summer, because we run the AC inside. However - when leaving the garage closed, temperatures reach roasting levels better suited for cooking than ...
0
votes
1answer
28 views

Calculating total energy savings for LED lighting

I'm redoing all the electrical in my entire house, and I was running some numbers just for fun on the energy efficiency gains by just having LED, vs incandescent bulbs. I know the basic LEDs use much ...
0
votes
2answers
65 views

when freezers are not in use fr 2-3 weeks a month, should they be left plugged in?

I work with a food pantry at my church. We receive food on the first Thursday on the month and distribute food to those in need on the following Tuesday. We have several chest freezers which we use to ...
1
vote
2answers
119 views

Is it economically reasonable to cool the roof by water evaporation

I want to estimate the outcome before going into hassle of installing the sprinklers/mist emitters. I have a place on the last floor, you can call it an attic, directly under a flat roof which is ...
1
vote
1answer
91 views

Home: Using Exhaust & Circulating Fans to Improve Air Quality While Staying Cool

In the hopes of ventilating nasty odors and airborne contaminants, I recently installed the Bionaire BW2300 in one of my kitchen windows. This is the only one I have installed in my home at the ...
4
votes
3answers
124 views

How can I improve efficiency of my home? Geothermal not saving money

I've been getting very high electric bills since moving in last August. My winter months have averaged $350/mo and so far this spring has been the same. I live alone, work 8 hours a day, do 2 loads of ...
-1
votes
1answer
126 views

When is a variable-speed compressor HVAC unit worth the cost?

Surprise, its summer and our AC broke down. We were quoted prices for installation of the current standard (SEER 14) AC units (about $6500 unit cost and installation) vs Trane's SEER 18 AC units ...
2
votes
2answers
56 views

Photovoltaic installation: does it make sense (or is possible at all) to get a bigger inverter than the power output of the installed panels?

We are going to install a PV in our offices. Our actual needs would be satisfied by an installation of about 4kW, so that ~16 panels of 250W. It's going to be a central-inverter, grid-connected ...
0
votes
1answer
1k views

Does running a dehumidifier with an AC unit save money?

I've done as much research as i can an every site i hit seems to have a different story on my question: "Will a dehumidifier save energy while running your AC through the summer"? The ones that say ...
1
vote
3answers
43 views

Insulation type to use on a hinged metal attic door

In this question, I asked about the best type of insulation to use on a hinged metal attic door, when one is also concerned about heat entering around the edges of the door when closed. The answer I ...
1
vote
1answer
43 views

What is the best type of insulation to use on a hinged metal attic door?

What is the best type of insulation to use on a hinged metal attic door (no integrated ladder)? Primarily concerned about heat entry through the door when closed. Also concerned about heat entry ...
1
vote
1answer
89 views

How to estimate if an old AC is worth replacing?

Have a window AC unit that's from 2001, here are the specs: Manufacturer: Kenmore VOLTS: 115 Cooling BTU/HR: 12500 Cooling AMPS: 11.6 Cooling WATTS: 1275 Cooling EER: 9.8 The average electricity ...
3
votes
1answer
95 views

What's the best way to select windows for heating efficiency? I have an older house in a northern climate [closed]

I am sure that the Energy Star program is not going to help me. The USA Energy Star program helps people find energy efficient windows. It guides us to prefer windows with low U-Factor and low solar ...
0
votes
1answer
31 views

What is the correct Air Flow change per hour for my house?

I recently just got my house air sealed. Before air sealed the Building Air Standard (BAS) was 1.4 now it is 1.2. Based off a 1300 sq ft house. What should the BAS be? Is there a calculator to ...
0
votes
1answer
105 views

Best cost efficient plug-in heating devices / radiators

We moved to a 2-bedroom apartment that has baseboard heating devices installed. Our first electricity bill was huge (around $400) and we only used 3 of them and not all day long. Here is a pic of the ...
0
votes
0answers
21 views

How can I minimize energy consumption using my baseboard heating device?

Should I leave it ON most of the time and just play around with the temperature, or is it better to switch it OFF when I am not in the house and then turn it back ON?
1
vote
1answer
208 views

Do Dimmable LED on Standard Dimmers Save Energy?

A lot of new LED bulbs claim they work on standard dimmers. Bought a bunch of the Philips Slim Style Dimmable LEDs when they were on sale at Home Depot. They work fairly well on dimmers that were ...
0
votes
1answer
336 views

Carrier 60,000 BTU 92% Furnace vs Carrier 40,000 BTU 95% AFCU Furnace

I have about 900 finished square feet in my house, and I'll eventually be adding another 200 or so finished sq/ft in my basement. I'm looking to get my furnace replaced and have been quoted two ...
0
votes
3answers
222 views

Device to detect where heat or cold air is escaping or entering a structure

I would like to lower my environmental impact and reduce my energy bills by reducing areas where air might be entering or exiting my home. What type of device can be used to detect where heat or cool ...
1
vote
2answers
150 views

Can we capture the hot, humid air from a gas-powered clothes dryer during winter?

During winter we run a gas-powered heater and evaporative humidifier to maintain indoor air quality. Meanwhile, every day (big family!) we run a gas-powered clothes dryer which dumps hot, humid air ...
6
votes
1answer
130 views

Does anyone have experience with small heat-recovery air exchangers?

I know there are units made which are supposed to be sized for use in a residential kitchen, as a more efficient replacement for the usual vent hood (bring air in to replace air blown out, but ...
1
vote
0answers
39 views

How can I tackle thermal downdraught?

Thermal downdraught on windows is a fact of life. I understand the mechanics involved, but that doesn't make it any more comfortable! Short of replacing the glass in my double-glazed units with (yet) ...
1
vote
2answers
1k views

Best way to stop cold air coming in from fireplace

My house was built in 1967 and has a real working fireplace. The problem is, it allows a ton of cold air into the house. There is a chimney cap (and I climbed up on the roof to verify it still works), ...
1
vote
0answers
224 views

How should I seal and insulate a crawlspace to mitigate radon and allow for storage in the space?

Background: I recently bought a house built in 1996. It has a 1480sq ft (approx) living area, which is the same as the crawl space size. The location is in the Kansas City metro area. The yard is ...
0
votes
3answers
173 views

Old GE Fridge Wattage

So we have a GE Refrigerator that's around 35-40 years old. Purchases between 1983-1985. The fridge has not died yet. Yes i know, GE makes amazing stuff. And i was really thinking about replacing it ...
-1
votes
1answer
24 views

Viewing cumulative electricity usage [closed]

The TED 5000C monitors real-time electricity usage. This, however, isn't so useful if plugged into, say, a fridge, where, presumably, the bulk of the electricity usage is going to come from when the ...
1
vote
2answers
384 views

Can an IR thermometer be used to check wall insulation?

IR point thermometers have come down a lot in price. IR imaging cameras haven't. Is there a reasonable approach to using the point thermometer to determine how well or poorly insulated my walls ...
1
vote
1answer
588 views

Should I put a basement dehumidifier on a timer, or trust the hygrometer?

Dehumidifiers draw a LOT of power (as you might expect of something which is basically a modified air conditioner or refrigerator). I do want the humidity in my basement kept at a comfortable level, ...
16
votes
10answers
6k views

Is it more economical to use hot water before boiling or to bring cold water to a boil?

Since the arrival of our newborn, we have been using the stove to boil water in order to sterilize the nipples, bottles and rings. Which got me thinking, is it more economical to start off using hot ...
-4
votes
2answers
110 views

What is the best way to store energy?

I want to store 6 months of energy with one of these applications. which type of system would be the best way to store energy for a house, which last for approximately 6 months. (heating/air ...
0
votes
3answers
9k views

Unplugging vs running an empty refrigerator

We have a community Pea Patch that has 2 older refrigerators that are empty 5 days a week and used to store produce on 2 of those days. Does it take less energy to leave them running for those 5 ...
2
votes
1answer
231 views

Will a single ductless mini-split heat pump be able to distribute its air evenly throughout my ranch house?

I am in the middle of a deep energy retrofit of my house, and a quick-and-dirty online manual J calculation of the projected loads once my projects are completed shows an estimated heating and cooling ...
5
votes
5answers
2k views

Air sealing a whole house fan

I have a whole house fan installed in my house from the previous owners. I love the fan, as it lets me cool down the house quickly in the evening -- or after I fill the house with smoke from ...
1
vote
3answers
2k views

Why don't American homes have blinds on the outside of their windows?

Traveling through Europe, seeing many different construction methods, I try to take an objective look at why things are done a certain way. One of the most positive things that I see done in Europe ...
8
votes
2answers
807 views

Why are furnace/central AC blowers so inefficient?

I can buy a ceiling fan from Home Depot capable of moving 5,000 CFM of air for about $50, and it uses a mere 50-60 watts while doing it. By contrast, most furnaces seem to have blowers that operate in ...
0
votes
1answer
68 views

outlet bypass for multimeter

seeing that I (and i bet 99.9% of the people here) already have a nice multimeter, i find it kinda of silly to buy a kill-a-watt type of device. But, on the other hand, it is really impractical to ...
1
vote
4answers
875 views

Leave the water heater on?

When I lived in France and the US, we can an electric boiler for hot water. It was "always on", probably with a thermostat. Now I live in an area where most people have a power switch that they turn ...
2
votes
1answer
104 views

Is it really energy economy to use movement sensor for turn lights on?

I want to install those movement sensors in my house in replacement for the old light switch. I want to use those from elevator halls which has a 3 way switch to leave on, leave off and leave ...
0
votes
2answers
804 views

Energy efficient bulb takes a long time to get bright

Ive recently moved into a newly built house (im in the UK). When I turn my bedroom light on it takes a long time to get up to full brightness which is quite annoying. Ive unscrewed the lightbulb to ...
1
vote
2answers
109 views

What's the minimum amount of electricity used by an appliance?

My Kill A Watt P4400 by P3 International shows 3 watts electricity usage if anything is plugged in. Do things plugged in, regardless of whether they are ON or OFF, really use a minimum of 3 watts or ...
0
votes
1answer
76 views

How can we protect this furnace from environmental conditions?

I was recently asked to look over the utility closet of a friend, and several things I saw looked very concerning, from an energy-efficiency standpoint. This closet is approximate 3' x 6', and is in ...
3
votes
2answers
995 views

Can upgrading my boiler save me money?

I've just received my annual gas usage statement. It came as a surprise to me that I'm using almost the average gas consumption in the UK. The average is 16,500kWh and I used 15,000kWh over the year. ...
12
votes
3answers
3k views

Would providing shade for my air conditioner's condensor improve its efficiency?

Our house has two A/C systems; one for the bedroom level, one for the remainder of the house. The compressor/consdensor units are outside the south side of the house, and in direct sun all day, now ...
2
votes
2answers
671 views

What type of wiring should bedroom overhead lighting have?

On the phone with a friend in Cali this morning. He said that some municipalities are requiring /4 (12-3 or 14-3 romex) wiring for all new construction or rewiring for overhead lighting components. ...
1
vote
0answers
66 views

How do I maximize light gain and minimize heat gain for my glass wall?

How to get maximum benefit of daylight while optimizing air-conditioner benefit for a glass wall (currently) of size 11' * 8' (total 88 square feet exposed). Facts: The glass wall never gets direct ...
2
votes
1answer
146 views

Is it time to replace my water heater?

I have a 20+ year old, 115 gallon, electric water heater. Works like a champ, but I'm considering replacing it for a couple of reasons. It's leased - I pay $20/mo. It's 115 gallons for a house with ...
2
votes
1answer
596 views

Is a roof sprinker a good idea?

I live in an area where temperatures often reach 95°F (35°C). I have attic fans and soffet vents and radiant barrier. Is it worth adding a roof sprinkler? I have read about it working wonders ...