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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21
votes
6answers
3k views

How best can I discover what is up with my electrical bill?

This might be subjective, I don't know. However, it's a serious problem for me. My electrical bill is outrageous. It's three times as large as my next-door neighbor, and four or five times the size of ...
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 ...
13
votes
4answers
879 views

Which water heater types do you recommend?

I would like to upgrade my current water heater with one that Is able to produce/store more heated water so I won't run out Energy efficient Inexpensive What are the advantages/disadvantages to ...
13
votes
3answers
4k views

Is there a device that will allow a bathroom fan to run for 5 minutes after it is switched off?

There is one switch that controls the lights and fan in the bathroom. Users turn the light/fan on when they enter, and off when they leave. I'd like for the bathroom fan to run for a time after they ...
12
votes
3answers
402 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 ...
11
votes
3answers
2k views

Are tankless water heaters worth it in cold climates?

I was thinking of switching over to a tankless water heater, but a friend of mine said they are not good in colder climates since the water coming in is colder and takes longer to heat. Is this a ...
10
votes
6answers
17k views

Can I save energy costs by turning off the refrigerator for 1-2 hours every day?

Now that I'm looking into home automation, I'm thinking about automatically cutting off the fridge power from 3am ~ 5am. Given that modern refrigerators are well insulated, it should be able to ...
9
votes
4answers
15k views

Does lowering the blower speed of a forced-air furnace lower its efficiency?

My gas furnace has two options for the blower speed: MED, and MED-HI. It had been set on the higher speed, but that was too harsh, so I lowered it to the slower speed. Does that have any impact on the ...
8
votes
3answers
28k views

What's the difference between dimmable and non-dimmable LED lamps?

I have a large room in my house with 3 light fittings with a total of 10 40W GU10 bulbs. So, this is using 400W when they're at max output. (They're all on dimmer switches) I'm interesting in ...
8
votes
7answers
2k views

How can I audit my furnace?

I want to keep track of when my furnace is on, with an eye to reducing how much energy I use to heat my house. I could compare it with weather data (temperature, wind speed, precipitation). I could ...
8
votes
2answers
263 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 ...
7
votes
6answers
7k views

Is insulating an unfinished basement worth it? If so, how should I go about it?

I have an unfinished, well waterproofed basement with cinderblock walls and a concrete floor. All but the top 6 inches / 15 cm or so is underground. Would it be worth insulating the walls down there? ...
7
votes
2answers
4k views

Why are almost all of my house's HVAC floor registers placed near exterior windows?

My current house is a single story built over a crawlspace and all the HVAC registers are in the floor. In all of the larger rooms, at least one (and usually more) register was placed near an exterior ...
7
votes
3answers
717 views

How do I add an exhaust fan to an old attic?

Our house's attic retains a great deal of heat during summer. While we now have a good layer of insulation between the attic and the rest of the house I wonder if it would be worth it to add some ...
7
votes
4answers
5k views

Is it a good idea to pay for an energy saving audit of my new home

We have a newly built home but I'm not at all confident in the builder's prowess when it comes to energy conservation. Is it worth hiring someone (like our energy provider or other specialized ...
6
votes
2answers
2k views

Why does using a dimmer with this ceiling fan and lights cause energy saving bulbs to flicker?

At a hotel I manage we purchased 34 ceiling fans with two integrated light sockets that operate on a dimmer all controlled by a remote control. Obviously using a dimmer with fluorescent bulbs won't ...
6
votes
2answers
1k views

Are radiator reflectors as effective as claimed?

I recently completed a survey to determine the energy efficiency of my home. The results weren't great but got me thinking about the quick and affordable things I could do to improve things and ...
6
votes
0answers
69 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 ...
5
votes
4answers
2k views

What is the most economical and energy-efficient way to winterize windows?

We have vinyl windows (mostly double-paned) and live in a shady greenbelt in Seattle (i.e. wet and dark). We don't have much severe weather to worry about, just a pervasive damp cold that settles in ...
5
votes
2answers
374 views

Is there a way to find out how often your furnace is running?

With winter finally setting in, and being the first year in our new house I would like to put some sort of measurement on how often the furnace is working, before I get the bill. Are there any known ...
5
votes
2answers
782 views

When insulating with closed-cell Spray Foam, what ERV and HVAC resizing considerations should I bear in mind?

I am building a 2800 sqft, two-story brick home in Austin, TX. I have heard many good things about the benefits of insulating with closed-cell Spray Polyurethane Foam (ccSPF)1, and have requested ...
5
votes
3answers
549 views

Should I install external basement insulation that does not extend above ground?

Question : Is there a way to calculate energy savings for external, 2inch insulation on basement walls that does not extend above the soil surface, leaving the top couple feet of foundation wall ...
5
votes
2answers
154 views

Energy Audit (WellHome)

We recently had an energy audit done by WellHome, a new division of Masco, which is a manufacturer of many types of home/building fixtures and services. They seemed to do a very thorough job, using ...
5
votes
2answers
115 views

How should I landscape my yard to make my home more efficient?

At some point in the future, I plan on owning a home and I would like to use landscaping to improve both the appearance and energy efficiency of the property. I have heard that the right landscaping ...
5
votes
1answer
287 views

Is it possible to recover waste heat from a boiler?

I did a google search and came back with industrial products, but no residential prosucts. I have a System 2000 boiler and hot water tank. When the furnace is firing, the temp of the exhaust through ...
5
votes
5answers
562 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 ...
4
votes
7answers
6k views

Would putting a sprinkler on my roof help cool my home?

Anyone ever put a sprinkler on your roof to help out your A/C on unusually hot days? Just wondering if it helps.
4
votes
3answers
1k views

Where am I losing heat from my house?

My house is about 5 years old and our local building codes required a 5-star energy rating (Melbourne, Australia). This means there's solar hot water and both the walls and ceiling are insulated. But ...
4
votes
3answers
517 views

Calculate savings from/cost-effectiveness of installing a tankless hot water heater?

Following up on "Which water heater types do you recommend?" and "Are tankless water heaters worth it in cold climates", is there a way to calculate the point at which installing a tankless water ...
3
votes
3answers
16k views

How much less power does a three-phase A\C unit use as apposed to a 220v unit?

I'm planning to install a 5 ton central AC. I'm deciding between a condensing unit that runs on 220V and a costlier unit that runs on 207Y three-phase. My understanding is that three-phase motors use ...
3
votes
4answers
214 views

How do I determine if the energy savings are worth replacing windows for?

I have a house with an east-facing wall which is mostly windows. In the winter, during the day I almost never have to run the furnace because of how much the sunlight warms my house. During the summer ...
3
votes
2answers
4k views

Can I use a stairwell ceiling fan to save energy?

We have a two story house, with a small ceiling fan mounted above the main stairway. The house has separate thermostats for heating/cooling the upstairs and downstairs. During the day, we spend 90% ...
3
votes
1answer
379 views

Should fan on heat pump be delayed turning off when system stops?

I have a heat pump system with emergency heat. I have a Honeywell RTH7600D thermostat. When the heat is running and I turn the temperature down, the system immediately stops. Isn't this inefficient ...
3
votes
5answers
6k views

What are my options for replacing 50W GU10 lightbulbs?

I've been looking at replacing 50W GU10 halogen lightbulbs for something more energy efficient. Some people say that LEDs cannot give you the same light (even 10W LEDs), and to use 11W CFL instead, ...
3
votes
1answer
133 views

Understanding results of an energy audit

We had an energy audit done a couple of years ago on our 20 year old home. Basically, they hooked up a blower to the front door, and tested the amount of air leakage. The written report suggested a ...
3
votes
2answers
1k views

What is the process for draft proofing windows

I need to try to prevent drafts coming through and around my double glazed window units as much as possible. How can I go about detecting and sealing any leaks that are letting air through the window? ...
3
votes
2answers
612 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. ...
3
votes
1answer
859 views

What are possibilities of balancing 3-phase consumption?

A lot of homes have a 3-phase electric connection. Each of the phases has some appliances connected to it. That implies power consumption in any moment on each phase is different, we have an ...
3
votes
2answers
133 views

Is there an online way to check my appliance power usage?

I'm considering replacing my old appliances (refrigerator, washer & dryer) with a more efficient model. Is there a website or simple method to look up their measured power usage ?
3
votes
3answers
467 views

Shading windows from outside (awnings, shutters, etc) to keep house from overheating in summer

The back of my house faces west, and during July and August, the sun hits it directly in the afternoon through evening. On a warm day, this can cause the house to heat up quite a bit, so I'm making ...
2
votes
4answers
7k views

My fridge runs way too much - is this because it doesn't seem to be level?

My refrigerator runs way too much - is this because it doesn't seem to be level? It doesn't seem to be any other reason.
2
votes
3answers
1k views

How do I install plastic window insulation without damaging the trim?

I'm planning to install plastic window wrap on my windows for the winter, but the trim around the windows is nice wood and I don't want to leave a mark on it where the double-sided tape will be. I've ...
2
votes
2answers
7k views

How do I seal my baseboards from drafts?

Some rooms in my house have a pretty bad draft along the edge of the floor, where it meets the outside walls. But I am less than thrilled (to put it mildly) about the prospect of ripping out carpeting ...
2
votes
2answers
350 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. ...
2
votes
1answer
357 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 ...
2
votes
1answer
206 views

How do I fix an irregular hole in my heater closet?

The plumbers cut a roughly rectangular hole in the water heater/heater closet floor when fixing the drain pipe for the condensate line. The closet is located in the garage. There are two 2" PVC ...
2
votes
1answer
3k views

How do I prevent window drafts?

I live in Florida. I have noticed that in the Winter it seems that the cold air leaks through the windows and into the rooms. This, of course, raises my energy bill for heating (yes we have to turn on ...
2
votes
1answer
2k views

Is a space heater or my window heating unit more energy efficient?

My roommate and I have noticed that, since our apartment faces south and we live right by the Hudson, our apartment is starting to be quite chilly in the evenings, and oftentimes is cooler inside than ...
2
votes
1answer
85 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 ...
2
votes
1answer
110 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 ...