The Surprising History of Household Energy Consumption in Australia
I was just trying to picture the inside of a home back in the 1970's. Household energy consumption must have been pretty straight forward, right?
The phone had a simple dial and no power plug. You could still use it in a blackout if the telephone exchange had power.
There were no gaming consoles or computers to speak of.
The colour TV was still a little bit of a novelty. The TV probably didn't have an accompanying 'entertainment system' and myriad of other standby power hungry devices hanging off it.
When you pressed the off button, the appliance turned off.
Air conditioning systems were the exception, not the rule. [Did household's even have AC in the 70's?]
There was one light in each room. No endless banks of halogen downlights.
New homes were more likely to be well under 200 square metres in size and contain more people than today's 'average' 250 square metre homes.
So, if you asked me to put money on it, I would have said that household energy usage was drastically lower than today. Surprisingly, this is not the case.
So much has changed, yet energy consumption per capita remains roughly the same.
According to my analysis, household energy consumption was actually higher in the 1970's than it is today.
Per capita energy consumption, on the other hand, was only marginally lower. Average per capita energy consumption in Australia has risen about 15% over the last 35 years.
In other words: even though the number of people in each household has fallen (from about 3.3 people to 2.5 people), per capita usage has only gone up a little.
Average per-capita household energy usage in Australia (MJ/day) by year.
Increasing electricity and natural gas consumption
When you drill down on what fuels were being used in the 1970's the picture becomes clearer.
At the beginning of this post I was mainly imagining electricity consumption being less. Somewhat reassuringly, electricity consumption was much lower. It only accounted for around 30% of total residential energy usage.
Residential energy use by fuel type in 1974
That is in contrast to 2008, when electricity consumption accounted for about 50% of residential energy usage.
Residential energy use by fuel type in 2008
Essentially, we've replaced generally less efficient fuels (wood, coal briquettes, etc) with more efficient ones (electricity, natural gas). This doesn't mean we're polluting any less, it just means we are getting more energy services for a similar amount of energy used.
Now the challenge is to bring down our total and per-capita usage in these two areas of electricity and natural gas consumption. It is promising to see that solar energy, which didn't register a blip in 1974 now accounts for over 2% of household energy input.
Update from some more recent data:
- NSW Electricity Demand drops by 4%
- Electricity Consumption Lower in Tasmania, Victoria, South Australia
Original data sources:
- Australian Bureau of Agricultural and Resource Economics and Sciences, Energy in Australia 2010, Table F: Australian energy consumption, by industry and fuel type.
- Australian Bureau of Statistics, Document 3201.0: Population by Age and Sex, Australian States and Territories.
- Ryan McCarthy