Leilac and Heirloom sign global licence and collaboration agreements for Direct Air Capture

Calix is pleased to announce that Leilac, Calix’s 93% owned subsidiary, has signed a binding and perpetual global licence agreement and a collaboration agreement with Heirloom, a Direct Air Capture company.

Heirloom, whose investors include existing Leilac shareholder Carbon Direct Capital Management, as well as Bill Gates-backed Breakthrough Energy Ventures, Ahren Innovation Capital and Microsoft, will employ Leilac’s electric kiln technology to heat limestone to produce high purity CO₂, which will go for permanent storage, and calcium oxide, which is looped through Heirloom’s process to remove CO₂ from the atmosphere.

Phil Hodgson

Phil Hodgson

Calix CEO and Managing Director

Calix CEO and Managing Director, Phil Hodgson said:

“Calix is pleased to announce a binding and perpetual licence agreement between Leilac and Heirloom. Our partnership with Heirloom creates the opportunity to apply the Leilac technology into a new and rapidly developing market. It is also an example of our commercialisation strategy in action, with partnerships and licensing arrangements enabling our core platform technology to be simultaneously applied to multiple large addressable markets.”

Daniel Rennie

Daniel Rennie

Leilac CEO

Leilac CEO, Daniel Rennie continued:

“These agreements establish the collaborative foundation for the combination of two highly complementary technologies. Our rapid progress to date is testament to the dedication and ingenuity of both the Leilac and Heirloom teams. Together, we have the potential to deliver a significant impact on removing legacy emissions.”

Shashank Samala

Shashank Samala

Heirloom CEO

Heirloom CEO, Shashank Samala agreed:

“Heirloom is committed to our DAC facilities running on renewable energy and we’re excited to further a partnership with Leilac to achieve low-cost carbon dioxide removal at future facilities on the way to achieving gigaton scale.”

Heirloom projects

Following the memorandum of understanding in February 2023, Leilac and Heirloom have progressed the engineering and design of DAC plants using Leilac’s electric calcination and CO₂ capture technology, including a research and development campaign using Calix’s electric calciner pilot-plant in Bacchus Marsh, Victoria. This work is informing the design of new commercial DAC facilities.

Heirloom installations are targeted to rapidly increase in scale. Project Cypress, located in southwest Louisiana, USA, aims to capture more than 1 million metric tons of existing CO₂ from the atmosphere each year and store it permanently underground. Heirloom is one of two DAC technology companies participating in the project, and the project is one of two that were notified of selection by the U.S. DOE for up to US$1.2 billion in funding under the Bipartisan Infrastructure Law’s Regional DAC Hubs program.

Heirloom has also signed a long-term contract with Microsoft for the purchase of up to 315,000 metric tons of CO₂ removal over a multi-year period, in one of the largest carbon dioxide removal deals to-date.

CO₂ mountain

The licence agreement

Under the terms of the agreement, Leilac will receive a royalty based on the value of the CO₂ captured with the technology. The royalty will:

Have a floor price set at the greater of US$3/tonne of CO₂ separated in a Leilac kiln, or 3.5% of the prevailing CO₂ price for lime decarbonisation; and
Have a variable price based upon the total volume of CO₂ capture capacity installed and the prevailing CO₂  price or value, less the amortised cost of capital of the Leilac kiln per tonne of CO₂ separated.

It is expected that the floor price will be the initial royalty rate. As the technology application develops in scale and maturity, the costs of deployment may fall and cause the variable price to become the prevailing future royalty rate. As part of a collaboration agreement, Heirloom will contribute US$3m towards mutually agreed upon DAC and lime related research and development activities. Leilac will retain all intellectual property relevant to its technology.

The global and perpetual licence agreement covers the exclusive use of the Leilac technology at all future Heirloom DAC facilities, subject to conditions and the fulfilment of milestones by both parties. These include achievement of target CO₂ capture volumes by agreed dates and the delivery of technology performance criteria.

CO₂ mountain

Prevent, reduce, remove: a shared approach to CO₂ mitigation

Leilac and Heirloom’s partnership is designed to support a range of CO₂ mitigation efforts. The electrification of mineral processing, including cement, lime, iron and steel and critical minerals, can enable a transition from carbon-intensive to renewable energy inputs, preventing future emissions and improving air quality for local communities.

Some hard-to-abate industries, such as cement and lime, produce CO₂ as an unavoidable by-product of raw material processing. For these industries, effective and low-cost carbon capture and storage is essential to reduce emissions.

But decarbonising alone will not be enough to achieve global climate goals. The Intergovernmental Panel on Climate Change projects that carbon dioxide removal in the order of 1–10 billion tonnes of CO₂ per year could mitigate residual emissions and, in most scenarios, achieve net negative emissions to return global warming to 1.5°C, following a peak.

Leilac and Heirloom’s collaboration seeks to actively develop and support solutions across the three priorities to prevent, reduce and remove carbon dioxide emissions.

Shared benefits

The partnership enables the DAC industry to leverage and benefit from many years of investment and technology development, including from the European Union and the cement and lime industries. Leilac’s pilot plant in Belgium has more than double the current combined capture capacity of all DAC facilities globally.

In turn, Heirloom’s ambitions for rapid deployment of large-scale carbon dioxide removal – with significant government and private sector support – has the potential to aid industrial decarbonisation efforts, particularly the electrification of heavy industry at scale.

Daniel Rennie

Daniel Rennie

Leilac CEO

Mr Rennie continued:

“Leilac is excited to apply our core technology, developed for and with the cement and lime industries, to DAC. In turn, we expect our partnership with Heirloom will accelerate the development of electric calcination, as we work with all of our partners and clients in support of a just-transition towards an industrially sustainable low-carbon society. It’s a win-win arrangement that aims to maximise the scale and speed at which we can reduce industrial and atmospheric CO₂.”

Heirloom & Leilac’s unique approach to DAC

Heirloom’s DAC solution harnesses limestone, one of the world’s most abundant minerals, to provide a fast and low-cost path to permanent CO₂ removal. With a typical cost of approximately US$10-$50/tonne, limestone is inexpensive and easy to source.

Leilac’s indirectly heated calcination technology is being developed to efficiently separate and capture high purity CO₂ from limestone and produce decarbonised lime. The technology does not require the use of additional chemicals, solvents, or energy intensive processes to separate and capture carbon dioxide, enabling Leilac to target the most efficient solution for the capture of CO₂ from limestone. It is also compatible with a variety of fuel sources, including renewably sourced electricity.

Heirloom’s DAC technology uses lime in a novel carbonation process to directly capture CO₂ from the air and form limestone. This process accelerates the natural binding of CO₂ and lime from a period of years to three days, and without large energy requirements. After binding and removing CO₂ from the air, the reformed limestone is fed back into the renewably powered Leilac kiln, where the CO₂ is separated and captured, and the cycle begins again. The CO₂ removed from the air will be mineralised, where it is bound to rocks or other materials, or injected underground into existing natural geological structures, where it remains safely and permanently stored.

The integrated Heirloom and Leilac DAC solution will be 100% renewably powered to deliver the maximum net reduction of atmospheric carbon dioxide.

CO₂ mountain

Leilac DAC Infographic Heirloom’s Direct Air Capture process powered by Leilac’s renewably-powered electric kiln.

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