Who are we?

Premium Quality CDR

At InterEarth we believe Premium Quality CDR must be Cost Effective, Long Duration, Measurable, and do No Harm to others during its production.

Cost Effective

Many CO2 sequestration technologies, especially Direct from the Atmosphere CDR, have very large Capital and/or Operating Expenses, and/or are relatively inefficient, resulting in high break-even costs and an average commercial price of USD449/t (see chart below).

We believe this high price of existing CDR is a serious  impediment to its uptake and the near term achievement of Net Zero. To ensure Net Zero is achieved as quickly as possible (via emission reduction plus CDR) we believe total annual Net Zero expenditure should ideally not exceed 3% of the entity’s gross income (GDP, corporate revenues, household income, gross salary etc).

Our Premium Quality CDR price is benchmarked against the Puro. Earth BioChar CORC Price Index, the cheapest Premium Carbon Dioxide Removal on the market (~USD171/ t CO2 e).

Note: tree planting has a high risk of fire destruction within 100years, and many analysts do not classify it as Premium Quality CDR).

A worked example of the cost for the average OECD citizen emitter to achieve Net Zero solely from CDR is provided below. (See chart below right for some other OECD member nations)

Emissions by OECD Countries

Figure: OECD average annual CO2 emissions per capita is 8.3t

Source: The Australia Institute

Long Duration

Many CO2 sequestration technologies leak a relatively high proportion of captured CO2 back to the atmosphere, in a relatively short period of time. The longer, a high proportion of captured CO2 is removed from the atmosphere (the “Duration”), the better the climate change mitigation outcome. 100 years Duration is generally accepted as the minimum to qualify as Premium CDR.

InterEarth Dry Stack technology is based upon the fact that dried woody biomass which does not decompose or oxidise (burn) is a highly effective, efficient, on long lived store of captured atmospheric CO2. For example; a 3775 y.o. Eastern Red Cedar log was found to have retained >95% of its captured CO2.

Image: Prof. Ning Zeng with 3775 y.o. near-perfectly preserved Eastern Red Cedar log

Source: phys.org

InterEarth’s research demonstrates that 114 y.o dried Eucalyptus marginata (Jarrah) stored under Dry Stack (dark, dry, well ventilated, rot-, mould-, fungus-, termite-free, fire-proof) conditions loses zero capture carbon (see InterEarth 114 y.o Jarrah Study coming soon). The dried biomass within our Trial and Demonstration Dry Stacks has been sampled and analysed for Total Organic Carbon (TOC) every 30 days for since April 2022. Multi-element (CH4, CO, CO2, O2) gas analysers have been continuously monitoring Dry Stack exhaust gases since April 2023. We have a large and growing database providing direct and indirect evidence of dried-biomass-inert Dry Stack conditions and zero loss of captured CO2. (see InterEarth Dry Stack update coming soon)

To achieve permanent reduction in atmospheric CO2, shorter duration CDR must be replaced (re-purchased) at the end of its Duration. The shorter the Duration the less the environmental and commercial value of the CDR certificate.In our Puro. Earth CORC production facility registration we made a powerful argument that the Dry Stack sequesters atmospheric CO2 for a minimum of 100 years.

Measurable

Many CO2 sequestration technologies are unable to directly measure stored CO2 and rely upon modelling estimates. Different assumptions and modelling parameters can deliver different CO2 sequestration values , which creates uncertainty and erodes the environmental and commercial value of such CDR certificates. InterEarth’s Dry Stack CDR is simple and directly measurable. All stored biomass is weighed and analysed for carbon content (see InterEarth Dry Stack update coming soon)

Net Sequestered CO2 (CDR or CORC) is:

Gross Captured CO2

minus:

Total CO2 emissions from the entire supply chain and Dry Stack materials and construction

minus:

CO2 leakage from Dry Stack over 100 year period

Gross Captured CO2 is:

Average TOC of dried Biomass deposited into Dry Stack (bone dry basis)

multiplied by:

Total tonnes of dried Biomass deposited into Dry Stack (bone dry basis)

A worked example of the calculation of Dry Stack CORCs:

No Harm

Many CO2 sequestration technologies come with collateral socio-environmental damage. The most common of which is significant CO2 emissions from materials, construction or operation. For example, the production of biochar (material handling plus pyrolysis) results in the re-emission of around 50% of the captured CO2 stored within the biomass.

InterEarth’s Dry Stack technology is characterised by very low material, construction and operational emissions and near zero CO2 leakage; more efficient sequestration of photosynthetically captured CO2 and a better atmospheric CO2 outcome.

Our production and harvesting of woody biomass from low productivity, Dryland (<325mm rainfall pa) agricultural land has near-zero impact on global food production. Our carefully selected high productivity eucalyptus and acacia tree species yield around 5 times more (lower value) biomass per hectare than existing agriculture land use; creating more regional materials handling jobs.

Our selected trees achieve high biomass production rates from there extensive and efficient root system, resulting in very high water use efficiencies. Our trees draw down the local water table and are the only demonstrated solution to secondary dryland salination, the most prominent environmental crisis of global dryland agro-ecologies. Our tree plantings are already helping to alleviate dryland salinity on our Bowgada demonstration plantation.