I just recently changed my electricity retailer and am finally able to get hold of my household electricity consumption data by 30-minute intervals via the internet (data my meter has been collecting for 2½ years, but my prior retailer couldn’t provide).
Comparing this data with two other households' consumption illustrates what a striking difference a few simple energy efficiency changes in conjunction with solar PV (plus, no teenagers in the house) can make to a household's energy consumption profile. It also provides a few clues as to why Australian electricity generators find themselves in such a pickle over declining electricity demand.
Firstly, immediately below is the energy profile of what you might think of as a household with a standard profile which electricity companies have grown used to. Each horizontal row of boxes represents a day, with each coloured box representing a 30minute period of power consumption. The darker blue indicates low energy consumption, while lighter colours indicate higher consumption. During midday energy consumption is low (blue) as the parents are at work and the children at school. Then at about 4pm to 5pm consumption tends to lift to the colour yellow as people get home. Interestingly, it peaks at white around 11pm which may be households switching on the dishwasher and washing machine before heading off to bed.
Source: Presentation from Ben Burge, CEO Powershop - 2013
We then have a household, below, where the plasma screen television is left on for much of the day and overnight. This household doesn’t have as much yellow and white consumption peaks as household one, but it struggles to get consumption down to blue levels, with it stuck at red even after midnight. This is attributed to the plasma screen TV left on overnight in the child’s room but, given consumption is also often high around midday, they may also have an inefficient refrigerator. This kind of customers is a power generators best friend.
Source: Presentation from Ben Burge, CEO Powershop - 2013
And here’s the energy consumption profile of my house, below. The black sections from 10am across the middle of the day represent no electricity consumption from the grid at all thanks in part to a small 1.4 kilowatt solar system. This is in spite of the house being occupied during the day thanks to a young toddler.
Note that there were three hot days of 35 degrees or more over the period below. On these days electricity demand from the grid between 5pm to 7pm was close to zero. The day of Tuesday, February 13 (third row from top) is a bit odd with consumption much higher between 3pm and 5pm due to the mother-in-law going crazy cooking and cleaning.
What has to be concerning for electricity businesses is that my household’s consumption profile reflects a trend occurring across Australia, where households have shaved about a fifth off their annual electricity consumption within about four years.
Solar is part of it, but it’s not the only driver. In addition, energy efficiency regulatory standards can also take significant credit as well as general technological advances.
To break it down you have the following factors at work in my house, beyond solar:
– A newish refrigerator that is vastly more efficient than those of 10 years ago thanks to energy efficiency regulatory standards built on those implemented in the United States.
– Compact fluorescent lighting instead of the now banned conventional incandescent light bulb.
– A standby controller which switches off all the entertainment equipment after an hour of inactivity.
– An LCD-LED television which is vastly more efficient than plasma and has become the dominant technology.
– The use of very low energy consumption battery-powered mobile and tablet technology for entertainment purposes instead of higher energy consumption TVs, stereos and desktop computers.
– A six-star efficient thermally insulated home (the minimum regulated standard now) which reduces the need for air conditioning.
These technologies are steadily filtering throughout homes across Australia and have led to energy efficiency savings outpacing growth in the number of electrical appliances.
The one sore point is that halogen downlights have acted as a barrier to major efficiency gains in household lighting. But the rapid reductions achieved in the cost of LED lighting and significant improvements in their light quality mean energy-guzzling halogens are now also under threat.
In addition to these advancements above in my own home, air-conditioner energy efficiency has vastly improved thanks to government initiatives across Asia, particularly Japan. These are delivering gains in reducing winter heating energy consumption in Queensland and NSW where piped gas is not readily available.
Another factor is the proliferation of water-efficient showerheads (not relevant to my household) reducing the amount of electricity required for water heating.
What we are seeing emerging is the product of around two decades of effort by governments and the electrical appliance industry in Australia and around the world to reduce energy consumption and carbon emissions. This is documented in a range of government documents including a series of initiatives by the International Energy Agency.
It may mean the electricity industry gets beaten up black and blue, but they should have seen it coming.
