A Do It Yourself Plug and Lighting Electricity Audit

A Do it Yourself Home energy audit is easiest if electricity is used exclusively for plug load and lighting. In the event that it’s also used for heating and cooling, it’s best to call in a home energy auditor so they can help you track down the air leaks in your home and help you figure out where to add insulation, weather-stripping, and plug air leaks to bring your heating bills down — or you can calculate plug load in the non-heating season.

In our home’s case, I know our electricity use is entirely plug load and lighting since we use natural gas for heating, hot water and cooking. So, there are two parts to an electricity audit: the first involves calculating your lighting load, the second is calculating the appliance and other electronics load. Calculating the lighting load using the following method is straightforward since no extra equipment is required and all the information you need is written on the light bulb (usually).

Calculating lighting load: Decide whether you’re going to start from the top or bottom of your home, but work your way systematically from the front of your house to the back visiting every room, bathroom and closet that has lights. Note your ceiling lights, table lamps and undermount lights, their wattage and estimate how much time they’re on each day. Include closets if they have lights in them.

In our kitchen there are six 50 watt halogen lights that are on in the morning for 1 hour for six months of the year and 2 hours for six months. In the evening, the six lights are on for three hours in the summer and five hours in the winter. There are also two incandescent hanging lamps which are on for three hours in the evening. So, calculating the amount of electricity the kitchen lighting load for an average day (estimate 1.5 hours hotelarcangelo.com per morning, 4 hours per evening for a total of 5.5 hours per day).

• 6 lights x 50 watts/light x 5.5 hours per day + 2 lights x 60 watts/light x 3 hours per day = 2,010 watt-hours per day or 2 kwh per day. Therefore, in one month the kitchen lights use 61 kwh of electricity.

Repeat this process for every room in your house and add up your total lighting consumption at the end. The results will tell you how much of your total electricity bill is dedicated to lighting. In our house, I estimate that our lighting bill accounts for 20% of our total electricity bill before central air is turned on.

Finding your electricity hogs: So, if lighting only accounts for 20% of our home’s total energy use, where is the other 80% coming from? Appliances, computers, TVs, digital boxes, stereos, cellphone and game chargers, gaming stations, alarm systems, digital clocks and of course, air conditioning.

There are plenty of websites that will give you approximate information about how much electricity your plugged in electronics, small appliances and major appliances use. But if you’re Type A like me, then you might be interested in determining exactly where you’re using the most energy instead of just making educated guesses. There are a few reasons to do it this way: one is that the results may surprise you — perhaps you thought it was your four-year old dryer that was using the most energy, but in fact it might be your 15-year-old deep freeze — especially when you consider that it runs 24-7- 365. Another surprise might be seeing how much energy your TV-Surround Sound-Gaming System use — even when it’s off (because it’s not really off, it’s in standby, still drawing electricity, commonly referred to as phantom power).