Loads and Loads of Appliances

The very handy Powertech Plus energy meter

Have you ever wondered just how many electrical appliances are plugged in around your house and how much energy they are consuming? All day every day, many of them are beavering away, doing what they do, and like parasites, sucking down your electrical supply. In fact there is a term, ‘parasitic loads’ that refers to those appliances that run 24/7, just idling along, ready for action. These appliances are still on, even when not in use. The warm power supplies are a give away. And, like parasites, they are busy multiplying in most of our homes. I know as I’ve just had to find and measure the energy use from every one of the appliances and plug loads in my home. - There were 67 of them!

Biophilic Bungalow is being designed to generate 5% more energy than it uses, over a year. That means we need to carefully predict the annual energy use of the house and landscape. I bought myself a Powertech Plus meter which enables me to plug in individual appliances and measure their power, and energy use over time. It has been a tedious process, how much energy does it take to run your rice cooker, iron, vacuum cleaner, smart watch, electric toothbrust, NBN modem etc.?

So the results are now in and my best prediction (and it is a prediction as appliance use is always variable) is that our plug loads and appliances will consume nearly 2400 kWh per year. We are a four person family and likely to be typical of many other families in terms of the number and types of appliances we own. If you own fish tanks or run a workshop full of lathes and arc welders then your numbers will be very different!

The big new load on the block is the induction cooktop. It was always there, using lots of energy, but in the form of gas. Now it’s part of the household electrical load, with significant peak demand and annual energy consumption implications. However it is the a highly efficient, safe and healthy alternative to the gas cooktops of the past, so it very much part of the electrical future for every home.

What has been interesting, although not altogether surprising, is that 40% of our energy use is related to digital devices (the orange bars in the graph below). That is a lot of load and energy consumption that largely didn’t exist when I was a child and now we have than in just about every house. And making that possible is an ever growing national energy and data centre network.

The smart and low cost solution to reduce these loads is to just turn them off at the wall when not in use. Ideally set up a circuit in the house for connecting non-essential loads. Mark the power outlet so it is clear which ones are linked to the non-essential loads circuit. The problem is many of these loads are relatively small and distributed around the house, or can’t be switched off (NBN model for instanace). Its kind of a ‘death by a thousand cuts’ scenario.

So for our house, when we do size the photovoltaic system for the roof, we will need approximately 5 panels of 350 watts each just to generate enough energy over a year to feed our plug loads and appliances. But given a lot of that energy use occurs at night when the sun isn’t shining, we would either need to draw from the grid, or source that energy from our own battery system.

It does beg the question, just how will we function if the electrical grid goes down for an extended period of time. And that is another Living Building Challenge requirement we will need to address for our home. More on that later.

Appliance Annual Energy Use (kWh)