Sustainable Energy NZ #14 – how much energy hides in food and ‘stuff’

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), solarbiofuelsmarine 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).

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