Dave Bryce started monitoring his family's carbon dioxide emissions about 12 years ago. At the time, they were emitting something close to the average for a New Zealand family. These days, he and his wife are emitting about one-eighth of the emissions of an average family, he says.
Bryce knows this because he uses Landcare Research's Household Emissions Calculator, a free online tool that captures electricity use, transport and household waste and estimates CO2 emissions in kilograms.