CLIMATE SPECTATOR: Driving energy demand back 30 years
Last week I attended a presentation looking at just how much we could reduce household energy consumption within 10 years without loss of comfort or amenity, just by using technology already available. The results were striking.
In findings that should send chills down the spines of energy suppliers, co-author Lloyd Harrington outlined that it was technically feasible to cut household energy consumption (both gas and electricity) in half, compared to a business-as-usual path, within 10 years. This would mean energy consumption would be brought down to levels that prevailed when Back to the Future was at the cinema.
For those who've never heard of Lloyd Harrington, he is like a walking, talking encyclopaedia on the energy consumption of electric and gas appliances and equipment. He can cite passages from arcane technical standards governing everything from televisions to refrigerators to light bulbs. Then he'll proceed to tell you how some Asian appliance manufacturer managed to game the test procedure for refrigerators through some clever computer software.
I've even seen him manage to out-argue appliance manufacturers at Australian Standards meetings with his superior understanding of the technical characteristics of their own products.
Over the years he has steadily built up an incredibly detailed computer model of each of the different items influencing energy consumption in Australian households, down to the level of individual appliances. He has constructed this using in-house surveys, appliance sales data and cross checks against energy consumption data from government and utilities.
So, in other words, people should think twice before dismissing this analysis as the product of some starry-eyed greenie.
According to Harrington, the chart below illustrates Australia's historic and current path for residential energy consumption – without further government policy.
Australian household energy consumption by fuel-function type 1986 to 2020
Source: Energy Efficient Strategies and Beyond Zero Emissions
Interestingly, it illustrates that Australian household electricity consumption is likely to have already peaked even without further government energy efficiency interventions, and excluding the impact of solar photovoltaic power. However, gas use – mainly for heating purposes – continues to grow. (By the way, the large chunk of energy associated with wood is mainly a function of its high levels of inefficiency rather than being highly prevalent across Australian homes.)
Lloyd Harrington and his co-researchers then modelled a range of options for how we might upgrade efficiency and contain gas consumption, including the scenario illustrated below which aimed for a rapid phase-out of gas.
This research was undertaken for Beyond Zero Emissions as part of their Buildings Plan and complements its push for generating electricity purely from renewables – hence the desire to phase out gas in favour of electricity.
Australian household energy consumption under a rapid phase-out of gas with moderate upgrades to building thermal shell
Source: Energy Efficient Strategies and Beyond Zero Emissions
Under this scenario the stand-out feature is obviously the disappearance of gas for heating, cooking and water heating purposes. Instead, highly efficient reverse-cycle air conditioners are used for heating, induction cook-tops for stoves, and heat pumps with solar for heating water.
This leads to an increase in the yellow segment of the chart, which covers electrical heating and cooking relative to the BAU chart above. But it is a surprisingly small increase, and overall electricity use is 12 per cent lower than under the BAU case.
The reason they've managed to keep electricity use low in spite of phasing out gas is because they also:
1. Upgrade all existing homes with some relatively straightforward thermal efficiency upgrades, such as insulation and draught sealing (but not things like double glazing windows, which would be more difficult and costly);
2. Upgrade all electrical appliances to the energy efficiency of the best available technology already on the market today. This may sound impressive, but given underlying technological improvement and the 10-year time period, it may not be all that hard. The other day I went to a JB Hi-Fi store and found a large number of 32-inch televisions that consume less than 160 kilowatts per annum. When I bought my television there just two years ago you would have found equivalent models were consuming about 200kWh. Even the boring old refrigerator is expected to see a 30 per cent efficiency improvement when Australia matches the US energy efficiency standard, according to Harrington.
Now, as Harrington excitingly explained, this doesn't take into account the potential for solar PV to further reduce households' demand for energy.
Harrington points out that if solar PV were to maintain the sales levels achieved last year then it would shave off a further 45 petajoules – about a fifth of household energy demand.
Of course, this won't happen without government recovering some of its lost enthusiasm for energy efficiency. But it looks like Beyond Zero Emissions' forthcoming Buildings Plan will again force us all to think far harder about what might be possible, instead of taking the easy path of just saying it can't be done because it hasn't been tried before.