Four ways to lift annual targets to meet zero emissions

THE current global climatechange commitment is now focused on national targets of net zero emissions by 2050.

Net zero means reducing emissions as much as possible and balancing whatever is left by taking them out of the atmosphere. Likely possibilities are planting trees, storing carbon in the soil, or absorbing carbon dioxide from the air and burying it deep underground.

Since 2005, Australia’s emissions fell on average by 6.5 million tonnes per year. If we meet our 2030 target, net-zero by 2050 would mean average annual net reductions of 23 million tonnes year-on-year between 2030 and 2050. This is a big ask.

There are four main sources of Australia’s emissions.

Generating electricity is responsible for a third. This proportion has been falling consistently with a shift to solar and wind. A successful long-term shift means balancing more solar and wind with more transmission and storage. And we must solve the challenge of long, cold periods when solar and wind are in short supply.

Another 31 per cent comes from industrial activities: extracting coal and gas, mining, and minerals processing and manufacturing across many thousands of businesses.

The first step is to switch from gas to renewable electricity while developing renewables-based hydrogen for chemical feedstock and processes that require very high temperatures, such as metals and glass making. Uncomfortably, the future of emissions from extracting coal and gas lies in the hands of our customers.

Transport contributes 19 per cent. Switching to battery electric vehicles will dramatically reduce emissions for light vehicles, while hydrogen and fuel cells will probably provide the solution for heavy road freight. Aviation and marine transport emissions, a relatively small part of the picture, will be harder.

Agriculture contributes 15 per cent of our emissions, with cows and sheep being the biggest source. Changes in farm practices such as fertiliser and power usage could steadily reduce emissions. Solutions to burping livestock look harder.

Addressing climate change will bring costs. But an honest debate must also acknowledge the costs of not reducing emissions.

Tony Wood is the climate and energy director at the Grattan Institute.