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Energy Advisor: Let’s look at ‘phantom’ load

May 2, 2022 | Eric BenSalah | energy efficiency, energy savings, tips
phantom power

Does opening your blinds to direct sunlight actually warm a room? What exactly should you be looking for, energy efficiency-wise, when buying or renting a home? Do you need an energy audit – and what is that? These types of questions are rarely answered in typical energy efficiency tips.

For each month of 2022, OPPD’s Energy Advisor Eric BenSalah will provide insight into some of the lesser-known aspects of energy efficiency.

This month: Phantom load

This may be one of the most common efficiency tips you’ve heard or read: Be sure to unplug all unused electronics to save energy and money.

So, does doing that really make a big difference? The short answer is yes and no. (How’s that for clarity?) If you have seen our video on “phantom” load, you understand that answer. If you haven’t seen that video, be sure to check it out, and read on.

Add it up

Unplugging unused electronics (including appliances) does reduce your energy usage, but by a very small amount. As an energy-saving (and bill-reducing) measure, it is not very effective. You are better off simply turning the power off, or if you still want to unplug an appliance or device, connect it (and other electronics) to a power strip and turn that off. A few examples, based on eight hours of use a day:

  • Cellphone charger: Unplugging it when not in use will save you roughly 2 cents a month.
  • Computer/work setup (laptop, two monitors and speakers): Unplugging all of these when not in use will save you roughly 45 cents per month.
  • Entertainment center (LCD TV, speakers, audio receiver, two gaming systems): Unplugging all of these when when not in use will save you roughly 90 cents per month.

The numbers that are often cited in terms of savings when it comes to phantom load are calculated by the amount it costs to use the item and multiplying that by however many hours it is not in use. For example, let’s take a space heater. When operating on high, it uses 1500 watts or 1.5 kWh (kilowatt hours). At a cost of 8.63 cents per kWh, that’s about 13 cents per hour. But if you unplug the space heater for six hours, you will not save 78 cents (13 x 6).

phantom load
The watt detector plugged into the outlet is used to determine how much energy this appliance uses when it’s plugged in but not in use.

The amount of energy an electronic device or appliance uses when it is turned off is significantly lower than when it is in use. I used a watt detector to determine just how much energy a space heater uses when it’s plugged in, but not in use. The amount might surprise you: 60 watts in 24 hours, which adds up to roughly a half cent per day, or about 16 cents per month.

So, back to unplugging the space heater for six hours. If you unplug it, you’ll actually save one-hundredth of a cent per day. At a maximum, if you left the space heater unplugged 24 hours a day for an entire month, you would save yourself 16 cents.

To look at your possible savings more broadly: You might save about $1-3 a month if you unplug everything in between uses. So why is that tip so popular?

Working together makes a difference

The short answer is that one household following this process might reduce their energy load by 2.5 kWh in a day. But, especially during peak energy use situations – like a scorching hot or bitterly cold day – if 10,000, 20,000 or 50,000 customers do this for a day, the energy reduction across OPPD’s service territory drops by 25,000, 50,000 or 75,000 kWh.

In closing, yes, phantom load is real and you can make a difference. The reality of phantom load, however, is that is works on a larger scale, when we all work together as needed. On a smaller scale (e.g. in an individual home), it’s all up to you: How much effort do you want to put into reducing your energy use, cost and carbon footprint? Simply turning items off, or shutting off a power strip (or better yet: using smart plugs) will produce nearly the same effect for that effort.

April: Do these common tips hold true?

Energy tips come from a variety of sources: your local utility, the Department of Energy, a parent, a neighbor or maybe even your child. Many of those tips are oft-repeated: open your curtains to direct sunlight to warm a room or close them to help keep a room cool; or replace your light bulbs with LEDs to save energy and money.

Today, I am going to address those two particular tips and what the actual results are, along with some additional information to keep in mind.

Do curtains help control temperature?

Can you really warm a room by opening your curtains to direct sunlight or cool a room by closing the curtains to direct sunlight? This is probably the number one tip mentioned whenever EE tips are given out. But, does it actually work?

Using an infrared thermometer, with the curtain open, I checked the temperature of the window facing the sun, the wall next to it, and the floor on which the sun was shining. I also used a regular thermometer to determine the ambient air temperature (like your thermostat does). Here is what I found:

EE_Energy Advisor 2022 April thermometer

Outside temp: 88 degrees / Thermostat: 74 (set on cool) / Location: Living Room (about 10’ from the thermostat)

  • Curtain Open
    • Window: 93 degrees
    • Wall: 87 degrees
    • Wood Floor (receiving sunlight): 92
    • Ambient: 76
  • Curtain Closed
    • Window Curtain: 89 degrees
    • Wall: 87 degrees
    • Wood Floor (no sunlight): 82
    • Ambient: 73

Summary: Every home is different. The home I tested this in did not have adequate insulation in the exterior walls. However, from the data above, there is a change in temperature which affects our comfort from a radiative standpoint. In other words, if you’re close to a hot wall or floor, you’ll feel hotter and the same goes for a cold wall or floor. Opening or closing curtains to use sunlight to your advantage can work in most situations. Sunlight can warm a room by as much as 7 degrees depending on the design of the home, the time of year and other factors.

Should you only use LED bulbs?

The concept is simple: Replacing any incandescent or CFL light bulbs with LEDs will save energy, money and trips to the store to buy replacements. So, I have to ask: Is that true?

It is.

EE_Energy Advisor 2022 bulb composite

To understand part of the why, we have to understand how incandescent bulbs and LEDs create light. An incandescent bulb has a tungsten filament that gets superheated once an electrical current is established in the base of the bulb. The heat the filament gives off is so hot it glows which produces light. That energy is broken down to roughly 10% light and 90% heat energy.

An LED bulb has an electrical current that passes through a microchip which then illuminates tiny light emitting diodes (LED) to create visible light. That energy is broken down to roughly 90% light and 10% heat energy.

When LEDs first came on to the market, they were pretty expensive – as much as $5-10 per bulb! Now, you can buy a 6w (60 watt incandescent equivalent) bulb for as little as $2. Let’s break this down:

bulb chart

In doing the math, you will have purchased 6 incandescent bulbs for the lifespan of the average LED. Meaning you would have spent $6.00 when you could have spent $2.00 by purchasing an LED. And the usage difference? This is called the payback period.

On average, LEDs that replace incandescent light bulbs have a payback period of three months. Meaning, after 3 months, the savings from the LED (compared to the incandescent) will have paid for itself. After that, it’s all savings!

Due to the nature of LED bulbs – which use newer,  improved technology to produce light versus the tremendous heat used by an incandescent – they can be prone to failing in a short amount of time or right out of the box. However, on average, an LED will last 10 years or even longer.

There are many other tips to put under the microscope and analyze; be on the lookout for more in the coming months.

March: Benefits of an energy audit

For most of us, a home is the largest purchase we will ever make. A home needs regular maintenance (preventative and otherwise) just like we do, our cars do and so on. An energy audit is a great way to better understand your home as a system.

Energy audits are essentially inspections of a home with a focus on energy efficiency. Certified energy raters perform the audits and will inspect, test and measure various parts and aspects of the home. They will use the results they get to help the homeowner decide what energy-efficiency measures and/or retrofits (replacing an old technology with a new one) will work best or are at least cost-effective. An energy audit can also help ensure that the home is operating safely as it relates to combustion safety and air quality.

energy efficiency audit home
A certified energy rater will inspect your home with a focus on increasing energy efficiency and helping you save money.

Certified energy raters have a mission to conserve energy, increase energy efficiency and help you save money. Also, they are there to help protect the environment from byproducts of energy consumption, increase the comfort of the home, improve the health and safety of the home, and increase the public’s awareness of energy-efficiency measures and services.

The recommendations the energy rater will make can be as simple as behavioral changes in the way you operate your home. Or, a rater might recommend expensive retrofits, such as replacing a furnace or air conditioner, or making some upgrades.

What an energy audit includes

In order for the energy audit to be complete, a handful of tests generally will take place, including:

  • A blower door test, which determines how much air is entering or escaping from your home
  • A duct blaster test, which pressure tests the duct system for air leaks
  • Identification of all energy-using devices in detail (e.g. type, condition, energy consumption rate, etc.)
  • Current and potential health and safety issues
  • Home measurements (size, volume, fenestration, etc.)
  • Other pertinent items depending on the type of home and other variables

Once a complete picture of the home, how it operates, how you operate in the home, and other tests and variables are completed and evaluated, the energy rater will provide recommendations to the homeowner.

The recommendations will include (but not be limited to) items such as:

  • Behavioral changes that will reduce energy consumption or increase the health and safety of the home
  • Retrofit recommendations (where applicable) and the savings expected from those retrofits
  • Maintenance procedures and changes necessary to ensure energy conservation, efficiency and longevity of the current appliances or HVAC system
  • Potential future health and safety risks associated with any energy efficiency measure, retrofit recommendation and more, as well as mitigation of those potential future health and safety risks
  • Estimated cost for labor and materials pertaining to any retrofit recommendations

The energy rater will provide a written (on paper or digital) record of all recommendations and the report of the home.

If you are interested in having an energy audit performed on your home, check out either RESNET HERS Raters in Nebraska or BPI Energy Rater Locator to find a certified energy rater.

For more information regarding a home’s HERS (Home Energy Rating System) rating, see About the HERS Index.

February: Simple tips for a safe, healthy home

In the energy efficiency world, health and safety are just as important as efficiency and conservation. Whether you’re making energy conservation modifications and improvements to a current home or building a new one, health and safety hazards must be top of mind to avoid potential exposure to toxic and hazardous substances and situations.

By keeping some basic and important things in mind around the home, you can help to ensure you and your family are safe.

Below are some common possible hazards to be aware of and steps you should take to prevent or address them.

Carbon monoxide

  • Carbon monoxide is an odorless and tasteless gas. In your home, it comes from: motor vehicles and heaters and cooking equipment that run on carbon-based fuels (e.g., gas-powered stoves, furnaces, water heaters, etc.).

Carbon monoxide detector

  • The gas from fuel-based heating sources generally vents through a flue pipe coming off the furnace or water heater. Most newer furnaces have an inducer, which is essentially a fan that helps pull any carbon monoxide byproduct up and out of the house through the flue pipe.
  • Backdrafting can occur when gases start venting into the home instead of out of the home through the flue pipe.
  • You can purchase carbon monoxide readers from your local hardware store or online ($60-200) to monitor the CO level in your home.
    • A low concentration (5-50 parts per million [ppm]) can cause flu-like symptoms and may go relatively unnoticed.
    • A high concentration (50-3,000 ppm) can cause severe headaches, vomiting and potentially death.
  • Place carbon monoxide detectors in the utility room and living spaces of your home to alert you of any potential issues. A plug-in detector with a battery backup is recommended.

Indoor air quality

  • Byproducts from combustion appliances are among the biggest contributors to indoor air pollution.
  • Check or replace your furnace filter on a monthly basis, Generally speaking, a MERV rating of 11 or 13 works best to capture particles moving through the home when the system is running without causing airflow issues (too high of a MERV rating can cause airflow issues and damage to your HVAC system).

So, outside of installing some detectors and regularly changing filters, what else can can you do to keep your home environment healthy and safe?

Have a certified energy rater come to your home to get a full analysis, audit and more. You can search for a rater at RESNET Certified Energy Raters or BPI Certified Energy Raters.

Later this year, OPPD will launch a new Health and Safety sub-page under the Energy Efficiency section on The page will include information, videos and tips.

January: Choosing a new house or apartment

Homes now contain more and more energy technology than ever before. Even “updated” older homes can contain a smart thermostat or new HVAC system. All of this new technology means homebuyers need to assess all of their energy options when choosing a home if they want to be energy- and cost-efficient and safe.

There are plenty of things you have to do and think about when choosing a house or apartment. You can find a number of “walkthrough checklists” online to help you evaluate your next home. The tips below can help you ensure your home is in good working order – add them to your checklist.


  • Do all of the light fixtures and switches work?
    • It can even be helpful to bring a couple of LED bulbs with you to test light sockets with missing or burned out bulbs.
  • Remove any fixtures that cover the light bulbs to make sure they are in safe, working condition.
    • Old light sockets can wreak havoc on incandescent bulbs, causing the bulb to break with the plug still inside the socket. This leaves the filament out and can pose a safety risk, and broken bulbs are fairly difficult to remove.


  • For less than $10, you can purchase a receptacle tester (a fancy name for an outlet tester) that will tell you if the outlet is wired correctly, reversed, open ground, etc.
    • How an outlet is wired may not make or break whether you purchase or rent the home or apartment, but it will at least alert you to potential hazards to yourself or your electronics.

A ground fault circuit interrupter on an electrical outlet in a kitchen.

  • Are there outlets near water? Check around the bathroom sink, kitchen sink, etc.
    • If there are, check to make sure they’re ground fault circuit interrupter outlets, which  can detect  interruptions in the current and cut power within 1/30th of a second.
    • If they aren’t GFCI outlets, consider replacing them for safety.


  • Checking water pressure is important. Verifying that the waste water from the home is flowing properly is even more important. Turn on the sinks and showers then flush the toilets. In the basement, there will be a drain. You do NOT want that drain to back up under any circumstance.
  • If there is a large tree in the front yard, it is worth having an inspection of the main line to the sewer done to ensure the roots have not caused any issues with the pipe. That pipe is the homeowner’s responsibility if something were to happen to it (i.e. breaks, clogs, etc.).

Heating, air-conditioning and ventilation (HVAC)

  • Heating (furnace)
    • If the furnace has a humidifier, check the filter inside. These need to be replaced regularly, but are often overlooked. Mold and mildew can accumulate on them over time.
    • Make sure the drain lines coming from the furnace are flowing freely to the drain in the floor. You can pour warm water down the tubing to verify this.
    • Check for any damage on the flue pipe coming from the furnace up to where it vents up and out of the home. Any holes or damage could potentially leak carbon monoxide into the home.
  • Air-conditioning
    • Make sure the outside unit is in good condition.
    • The fins should be in good shape and clear of any debris (dust, leaves, dryer lint, etc.)
    • The unit should also be fairly level or on solid ground/mounting. (This is different from heat pumps, which are angled slightly back.)
  • Ventilation
    • You can do this once you move in: Be be sure to remove the return air registers from the wall and vacuum up any lint, dust, hair, etc., on the inside of the register as well as in the slot in the wall where it attaches.
    • If you have exhaust fans, be sure they are clean and clear of dust and lint; you can do this by using the brush attachment on your vacuum. Clogged exhaust fans or return registers cause unnecessary and damaging strain on the system.
    • Plan to go through one or two filters in a fairly short time, especially in older homes or if the home previously had pets.


  • If the home has a gas fireplace, be sure to remove the front covers and clean out any accumulated pet hair, dust, etc. Accumulated debris can pose a potential fire hazard; be sure to clean and maintain a gas fireplace properly.

Learn more about OPPD’s Energy Advisor program here.

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About Eric BenSalah

Eric BenSalah is an Energy Advisor for OPPD. After spending time in the field doing HVAC work, he joined OPPD’s Contact Center in 2012, assisting customers with energy efficiency and heating and cooling-related inquiries. Over the last three years, Eric revamped the Energy Efficiency webpages at and launched the new Energy Education Program. In his free time, Eric continues to play drums (for 30 years now) and is an avid reader of philosophy, astronomy, history and all things strange.

View all posts by Eric BenSalah >

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