The gas in Santos’s Barossa field contains approximately 18% carbon dioxide (CO2), a high concentration that requires separation before it can be piped to the Darwin LNG facility for processing. This high CO2 content makes the project one of the most carbon-intensive gas developments in the world, and a portion of this separated CO2 is vented into the atmosphere as part of the extraction process. 

Why the CO2 needs to be separated 

• Pipelining:The CO2 must be removed to allow the remaining gas to be pipelined onshore to the Darwin LNG facility. 
• Product Specification:The CO2 must be removed to meet the product specifications for natural gas. 

The impact of the high CO2 content

• Atmospheric Emissions:The significant volume of CO2 removed from the Barossa gas is a major source of greenhouse gas emissions, with a portion being vented into the atmosphere. 
• Carbon Intensity:The high CO2 concentration makes the Barossa project significantly more carbon-intensive than other gas projects in Australia. 
• Regulatory Scrutiny:The high CO2 content is a key factor in the project’s interaction with Australia’s Safeguard Mechanism policy. 

Typical energy stored in LNG is 50MJ/kg. MJ is useful unit of measure for energy in short durations, seconds or less. For something we can relate to, it makes more sense to convert to kWh, the units of energy we see on our electricity bills. Result is 180 kWh/kg. This doesn’t allow for energy used to facilities at ports to load and unload at source and destination, regasify LNG or inefficiency when used to make heat on stove top or space heater, relatively inefficient appliances. All electric homes typically use less than 10kWh per day but 360kWh consumed before you feel the warmth.

It’s probably generous to guess less than 10% efficiency,which means just 1/10th of energy if gas was burnt at well head travels as far as conversion to heat at your space heater. Or 360 in for 18 keeping you warm!!

Such inefficiency is why our governments are offering incentive payments to change to All Electric homes, using so much less energy at so many fewer $.

To keep LNG liquid while travelling on a ship, insulation isn’t perfect. So it needs shots of cooling. How? With BOG, boil off gas, going where? To ship engines or atmosphere. Gas might be as bad as coal, if not cycled through LNG, obviously worse with inefficiency of LNG.

And Trumpelstiltskin just commanded EU to buy $750Billion of LNG from USA.

In other countries public pressure has been enough to make advertising of gas and other fossil fuels illegal. This improves human health as well as budget health, reducing cost of living in economic hard times. You might like to add “no ads” in letters to your politicians.

It takes a lot of energy to chill methane/CO2 mix down to – 162degC then allow CO2 to boil off as waste. Industry dominated by few large players means they’re shy about divulging performance figures. Efficiency depends on purity of methane, removing CO2, other flammable gases, grit and acidic vapours which could freeze and cause failure. Persevering, they suggest looking at energy stored in LNG instead of energy to make it.