Introduction and Context
We have grown so reliant upon home electronics that we hardly notice them! In the US, most houses contain several televisions and computers, often paired with their own support equipment. The list goes on: speakers, printers, displays, cable box, DVRs. And what about smaller appliances and battery-powered devices such as coffee makers, vacuums, and tools? Not to mention our tablets and phones, for which we often plug in multiple chargers around the house “just in case.” Though individually small, in aggregate these devices consume more power than we may imagine. Worse, they can drain electricity even when not in use. However, once identified, we can avoid at least a portion of these vampire loads (also known as ‘phantom’ or ‘idle’ loads)!
But First: A Little (Easy) Math
To understand the scale of vampire loads, we note that we measure power in watts (W). Most of us are familiar with a 60W bulb (hopefully more often replaced with a 9W LED!). If that bulb operates 24/7 for a full year, it consumes 60 watts x 24 x 365 = 525,600 watt-hours of energy. Because this number is large, we prefer to quantify in kilowatt-hours (kWh): in this case 525.6 kWh. On average, we pay about $0.12 per kWh in the US. At this flat rate, that 60W bulb costs $63.07 for our year’s non-stop use.
Of course, most of us would NEVER leave the light on all the time! Particularly since a typical incandescent light bulb would only last 1,000 to 1,500 hours before burning out! But, effectively, that continuous use is EXACTLY what we suffer with respect to vampire loads.
What the Math Means for Vampire Loads
Think about all the watts required to maintain those chargers and other devices, often warm to the touch even when not active. On average, these loads account for less than 5 watts each. But together, they add up! Especially if you look at big loads like a DVR (23-49 W), digital cable boxes (13-30 W), and televisions (0-22 W). The graphic below from the Lawrence Berkeley National Laboratory helps illustrate these loads and others.
Since on average, each watt of vampire load costs us a little over $1 per year, costs add up! In fact, a 2015 report from the National Resources Defense Council found that vampire load accounts for about 23% of annual household electricity consumption.
What the Math Means for YOU!
By now, you may wish to learn how much money you are spending on vampire loads — and better yet, how to avoid them! But who has the time to run through all the calculations on their own?
Fortunately, you don’t have to! Duke Energy has put together a really simple calculator that helps expose your annual spending on idle load. Your only requirement: to count or to estimate the number of each device listed in the calculator. The tool then does the math for you. A good feature of the Duke Energy calculator is that it only examines vampire loads that we consumers can avoid by unplugging or using smart power strips or plugs (see below!).
Speaking personally, I ran through the calculator and “discovered” that I likely spend at least $125 per year on my vampires. Time to get to work slaying them!
Savings Calculations for the Vampire Loads We Avoid
In calculating savings in its app, Emporia Energy considers that with diligence we can avoid a large number of vampire loads in our homes. Two strategies exist for removing these loads. As a first step, we can unplug devices such as chargers while not in immediate use. Though effective, this strategy may prove inconvenient for frequently used devices. Or difficult to reach outlets! Therefore, as a second step, we can employ smart power strips or plugs. Aided by connected WiFi and mobile apps, these aids prove highly useful! And they shine best in locations where we concentrate multiple problematic devices: in the office, the kitchen, the family room, or the garage.
Although the NRDC report cited above points to 23% of household electricity drained by vampire loads, Emporia recognizes that only a portion may be eliminated. Therefore, we expect actual savings to fall within a range of 5% to 10%. As with other savings calculations, the Emporia app scales these savings based upon the level of user engagement.
Ultimately, we encourage combining the above strategies to avoid vampire loads (e.g., smart power strips) with others. And in so doing, we believe consumers will achieve as much as 50% savings on energy. Of course, tracking progress relies upon the ability to measure electricity use. So make a modest investment in a Vue energy monitor today to prepare you better for tomorrow!