AGL understands the transition to a low carbon future requires a range of solutions, so ten years ago we partnered with the CSIRO and others in the research around carbon capture.

Last week marked the tenth anniversary of the pilot program to capture carbon at AGL Loy Yang. At the milestone event the CSIRO hinted at the possibility of a new venture to investigate the use of carbon dioxide and heat in a commercial greenhouse application – in this case – in growing tomatoes.

“We don’t want to sit back and wait to see what happens in terms of our energy landscape, we want to lead the way, and hosting this type of research allows us to test what technologies may be available now and in the future.”

Carbon capture pilot explained

Loy Yang has collaborated with CSIRO on Post Combustion Capture (PCC) trials since 2008, when power station flue gases were captured in a pilot plant - a first for the southern hemisphere.

Then in 2016 a post-combustion CO2 capture pilot plant was constructed building on the CSIRO’s existing program. The joint venture included Japanese consortium IHI, Brown Coal Innovation Victoria and AGL.

AGL Loy Yang Acting General Manager Nigel Browne said the pilot plant has been successful, with the CO2 capture ratio maintained approximately 90% of the 5000 man-hours of the trial.

“We’ve done what we set out to achieve which was understand and successfully demonstrate the capture process. Furthermore, we’ve achieved a 40% reduction of energy used in the process. This has only been possible through the partnership with the CSIRO and IHI,” he said.

“250 tonnes of CO2 have been captured over the past 10 years. The process is catch and release, which means all gases are taken from the flue gas duct and returned to the flue gas duct.

“The consortium’s investigations have led to an improved understanding of how such technologies could be applied at scale, which now provides insights to other economic opportunities, both of which are obviously critical in a carbon constrained future.

“We understand geological storage of CO2 is the main option to lower CO2-emissions from brown coal-fired power stations and the CSIRO is involved in a number of projects to investigate and demonstrate this option.

“The CSIRO is looking at a number of options that use the CO2 capture for beneficial uses such as increased greenhouse productivity or commercial applications and a binding CO2 in minerals.”

“At this stage carbon capture and storage isn’t a commercially viable solution for new coal-fired power stations or retrofitting older stations which is why we’re looking towards an energy mix for our new investment as older stations are retired.”

What’s this got to do with tomatoes?

The next stage was mooted between the PICA plant and Flavorite, a Gippsland based producer of hydroponic tomatoes and supplier to major supermarket chains.

“Parties are preparing to enter into a memorandum of understanding to undertake a pre-feasibility study that would utilise heat and C02 produced at Loy Yang to enhance plant production at their greenhouses,” Nigel Browne said.

“The study concept aims to understand how AGL Loy Yang might host a greenhouse facility at the Loy Yang complex, utilising waste, heat and CO2 captured from the power station. With the produce being transported back to Warragul for packing and distribution.

“Additional CO2 captured has the potential to be utilised within the local and Melbourne food and medical markets.”

Key facts

• PICA is a PCC pilot plant project collaboration between IHI (Ishikawajima-Harima Heavy Industries), CSIRO and AGL, with secondary participation from Energy Australia and Federation University.
• The $5.3M PICA plant is connected to Unit 2 of the Loy Yang power station.
• It has a small footprint 8mx4mx19m tall and runs 24 hour a day.
• Over the past decade 250 tonne of CO2 have been captured and then released.
• AGL Loy Yang is based in Victoria’s Latrobe Valley.
• The project has supported six PhD projects at Monash/Federation University, Gippsland campus.

How does the PICA plant work?

The PICA plant takes a slip stream of flue gas from the Loy Yang A power station and passes it into the PICA pilot plant. The first stage of the PICA plant is a pre-treatment stage where flue gas is cooled and processed in a packed column where the flue gas reacts with a caustic solution to remove pollutants such as SO2, SO3, NO2 and removing additional ash.

The pre-treated flue gas then flows through to another packed column, called a CO2 absorber, where the flue gas reacts with a CO2 capture absorbent (IHI’s ISOL-162 or CSIRO’s CAL008) to remove 90% of the CO2 from the flue gas.

The remaining flue gas then passes through an emissions control column where traces of absorbent and other contaminants are removed before being returned to the flue gas stack.