Welcome to the fourteenth post in the Sustainable Energy without the Hot Air – A New Zealand Perspective series. After our previous posts on hydro power, geothermal and wind (and a summary on the big three), solar, biofuels, marine and waste energy, we’re now looking at answering the question:
How can we achieve a BIG reduction in our personal and national energy consumption?
Remember, as before, the units are in kWh/day/person – ie. if you ran a 40W lightbulb for 24 hours, it’d take ~1 kWh over the space of a day. We then divide it by person to give you a sense of the scale of the resource proportionate to the size of the population. Be sure to check out the methodology. For reference – we’ve been looking to replace around 55 kWh/d/p of energy currently generated by fossil fuels.
Farming and food processing cost about 8kWh/d/p of the NZ energy bill, much of which is of course exported. This is only energy consumed in food production – a great deal more energy is directly incorporated into our food from the sun. When looking at land for either biofuel or solar production, energy production competes directly with food. We could grow a lot more biofuel if we produced a lot less milk, for instance. For the purposes of national energy supply, we doubt much can be gained in terms of energy efficiency to support current production.
New Zealanders eat more beef than the UK population, but we eat next to no grain-fed beef and barning is rare. Overall, the 15kWh/d/p for a UK person is probably pretty similar here. Reduce that to 10 for vegans, but remember that crops cannot be grown on much of the land that we graze (especially not continuously).
The remaining energy budget, 28kWh/d/p, disappears into concrete, steel, cement, and our industry, which we can describe as making stuff. Buying less stuff would obviously reduce energy demand, but it is hard to otherwise identify what saving can be made in this area in terms of efficiency. Energy cost is a significant factor in making stuff so economic factors usually work to maximise efficiency in the larger scale projects.
Not included in the 88kWh/d/p from the Energy Data File is the energy that we import as stuff. We are burning coal in China for every Chinese-made appliance or clothing item that we buy. MacKay estimates 48kWh/d/p at least. Looking over our list of “stuff”, we would have to conclude “at least” as well. It is hard not to conclude that a significant way to reduce energy use in China would be for us to buy less stuff, buy stuff that will last, and use it for a very long time. Tossing out a cellphone or laptop because the battery has run out is not good but product lifecycle data suggests that this is what many people do. The average lifetime of a cellphone is 18 months (or less if you buy a new iPhone every time it comes out!). This calculation of 48kWh/d/p though is tough and we have considerably less confidence in it compared to other calculations we have used.
We, like McKay, don’t have any concrete suggestions for how to reduce this other than to encourage less consumption of this ‘stuff’ and to buy things of higher quality that will last longer.