Brown hydrogen is produced by exposing coal to heat, oxygen, steam and pressure, in a process called ”coal gasification”. Alternatively, heat, pressure, steam and industrial catalysts can also liberate hydrogen from natural gas, in a process called “steam methane reforming”.

But to be considered clean, both those methods need to be complemented by carbon capture and storage if they are to play in the emerging market for clean hydrogen.

In the national hydrogen strategy released last year, Chief Scientist Alan Finkel expects carbon capture rates of at least 90 per cent will be the minimum expectation.

Enthusiastic efforts to support CCS have so far proved costly for Australia and can boast only limited success.

The third, and cleanest, hydrogen manufacturing method uses renewable energy to create an electric current that splits water into oxygen and hydrogen.

2. Energy storage

Stretch goal: long duration energy storage (6-8 hours) dispatched at less than $100 per MWh

The variable nature of wind and solar power means storing energy is a crucial part of the energy transition away from fossil fuels. Battery powered electric vehicles (EVs) are also expected to ramp up in the coming years.

Large-scale battery installations and small battery packs attached to rooftop solar are springing up across the electricity grid to store energy and smooth out variable power supply in the grid.

In South Australia, the “big battery” at the Hornsdale Power Reserve run by French company Neoen, is being used to make the grid more resilient and avoid blackouts.

AGL recently unveiled plans to roll out a series of large batteries at the site of the ageing Liddell coal fired power plant.

3. Low carbon steel and aluminum

Stretch goal: Low emissions steel production under $900 per tonne, low emissions aluminium under $2700 per tonne.

The steel, cement, aluminium and chemicals industries combined generate about 30 per cent of the world’s greenhouse gas emissions.

No matter how much they convert to using renewable energy sources to power industrial factories and plants, the chemical reaction involved in making steel and cement produces vast amounts of carbon dioxide.

Experts say that however laudable the 2030 emissions reductions ambitions of the likes of steel billionaire Sanjeev Gupta or ASX-listed steel giant BlueScope are, a game-changer in industrial processes is required.

The grand plans of the world’s biggest steel maker, ArcelorMittal, include using more clean energy sources like hydrogen rather than fossil fuels. It is also working on carbon capture and storage, storing the gas for re-use in industrial processes.

In the city of Ghent, the steel maker is working trying to capture waste gas from a blast furnace and converting it into bio-ethanol.

4. Carbon capture and storage (CCS)

Stretch goal: CO₂ compression, hub transport, and storage under $20 per tonne of CO₂.

Carbon capture and storage technology has been backed by the likes of the International Energy Agency (IEA), International Panel on Climate Change (IPCC) and fossil fuel lobbies to reduce emissions but enthusiastic efforts to support CCS have so far proved costly for Australia and can boast only limited success.

There are two main applications for CCS: to mitigate fossil fuel emissions generated to make electricity via coal and gas, and for heavy industry, as mentioned above.

In the years since the first push to explore the technology under the Howard government in 2002, several pilot projects using the technology in coal-fired power generation either fell by the wayside or were completed without any commercial follow-up due to high costs.

The Australia Institute estimates $1.3 billion of taxpayer money was spent on CCS research from 2003 to 2017.

A $2.5 billion-plus project at Chevron’s $US54 billion ($82 billion) Gorgon LNG venture on Western Australia’s Barrow Island started up last August more than two years late and is not yet up and running to full capacity.

5. Soil carbon

Stretch goal: measurement for less than $3/hectare/year.

Cattle produce most of Australia’s methane emissions and agricultural soil is a major source of the nation’s nitrous oxide emissions. And unfortunately for farmers, not all greenhouse gases are created equal, with every tonne of methane or nitrous oxide thought to carry much more global warming potential than a tonne of carbon dioxide.

In the agriculture sector, there are opportunities to improve soil carbon levels and livestock productivity as well as deploying technologies to enhance fertiliser use, carbon storage in vegetation and improve fire management.