Decentralised Direct Air Capture The most sustainable, affordable and scalable way to produce clean CO2 on demand

Project Information

DDAC

Grant agreement ID: 101145402

DOI

10.3030/101145402

Project closed

EC signature date 11 March 2024

Start date 1 January 2024

End date 31 December 2025

Funded under

• The European Innovation Council (EIC)

Total cost

€ 3 545 125,00

EU contribution

€ 2 481 587,50

Coordinated by

SKYTREE B.V.
Netherlands

Periodic Reporting for period 1 - DDAC (Decentralised Direct Air Capture The most sustainable, affordable and scalable way to produce clean CO2 on demand)

Reporting period: 2024-01-01 to 2024-12-31

Summary of the context and overall objectives of the project

The goal of this EICA project is to bring Skytree technology from its current TRL6 (1kg pilot validated in industrial environments and technology scaled to the 5kg unit Alpha version) to TRL9 (200kg commercial unit validated and certified, and production processes in place to enter the market) in 3 years. To achieve this, we will scale and refine the technology, develop and validate alpha and beta system units, and outsource and certify industrial production.
Project objectives:
1. Optimise and scale up Skytree's core technology:
● Identify strategic customer needs and integrate them into the product.
● Optimise different parameters of our sorbent materials (CO2 capacity, regeneration temperature, lifetime, recyclability).
● Scale up the filter design focusing on an easily scalable modular architecture including an energy-efficient heating system.
● Develop an expanded control system allowing communication between the different elements of the equipment and the greenhouse.
● Implement AI/data-driven software to optimise usage and automate monitoring.

2. Fine-tune scaled-up core technology and validate its performance against the product specifications both in-house as well as in the field.
● Define & build the preliminary design of the 200kg alpha prototype.
● Analyse & refine the system design through in-house testing.
● Build the final design of the 200kg alpha prototype and test its performance in field

3. Further refine the final design of the product and verify the system's reliability and longterm operation against specifications, both in-house as well as in the field.
● Define & build the final design of the 200kg beta prototype.
● Evaluate in-house the system's long-term functionality, durability and safety, and refining the design.
● Build the final design of the beta prototype and test its continuous operation with customers.

4. Outsource and industrialise production and certify both the product and the manufacturing processes to launch a highly innovative product of the highest quality on the market.
● Transfer production to contract manufacturers for scaling.
● Certify the product to industry standards.
● Create a 3rd party validated LCA of our product and technology

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The performed activities have been focussed on scaling Skytree's Direct Air Capture (DAC) technology by transitioning from a cyclic adsorption/desorption process to a continuous operation process with 2 sections, significantly improving CO2 capture capacity and efficiency. During the reporting period the focus has been on further advancing hardware designs combined with development activities focussed on a data driven control system to optimize performance, energy use, and scalability under varying environmental and operational conditions.
Initial phases in this period of the Stratus project focused on conceptualizing and testing innovative reactor designs. A gravity-fed packed bed filter was selected for adsorption, while a vacuum desorption reactor with a plate heat exchanger was chosen for desorption. Testing of the proof-of-concept prototype in Skytree’s lab revealed key challenges, including airflow channeling and heat exchanger inefficiencies. Lessons from this phase formed the basis for the development of the Stratus Alpha prototype, designed to capture 400 kg CO2 per day with enhanced sorbent handling and industrial-grade components. Note that the original plan was to scale the technology to 200kg, however market insights resulted in a further scale up to 400kg/day capacity in the period under review.
Early static tests of the Alpha prototype demonstrate viable CO2 productivity levels. The system is now undergoing integration and continuous operation testing to refine scalability and energy efficiency.
In parallel, a AI/data-driven control system prototype to optimize the operation of the Stratus DAC units is being developed. By leveraging machine learning, IoT sensors, and cloud-based analytics, this system dynamically adjusts parameters such as adsorption/desorption cycles and sorbent flow rates based on real-time ambient conditions, user requirements, and forecasted energy costs.
Key advancements include: Predictive performance models for varied environmental and economic scenarios. Optimization algorithms to maximize CO2 capture while reducing costs and environmental impacts. A modular, adaptive control architecture that ensures scalability for diverse applications.
These advancements validate the technical and operational feasibility of the Stratus Alpha prototype and establish a robust foundation for future iterations. Next steps will focus on continuous operation optimization, automation enhancements, and energy efficiency improvements to support large-scale CO2 capture deployment in industrial and greenhouse applications.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The Stratus project marks a transformative step in scaling Skytree's DAC technology from the small-scale Cumulus system to a continuous, high-capacity CO2 capture solution. Through iterative development and testing, key insights were gained into challenges such as continuous sorbent handling, airflow distribution, and heat exchange efficiency. Initial PoC tests revealed limitations, suh as uneven flow distribution, which were addressed in the design of the Stratus Alpha prototype.
With an updated target capacity of 400 kg CO2 per day, the Stratus Alpha prototype integrates industrial-grade components, improved airflow management, and advanced sorbent transport systems. Early tests suggest the system is on track to achieve performance goals, with ongoing efforts focused on optimizing energy efficiency, operational reliability, and scalability. These advancements position the Stratus system as a viable solution for large-scale CO2 capture.
Complementing the hardware advancements, the AI/data-driven control system under development for Stratus DAC units delivers significant performance enhancements. This system optimizes operations by dynamically adjusting to real-time conditions such as temperature, humidity, and energy costs. Key achievements include validated improvements in CO2 capture efficiency, energy consumption, and sorbent longevity through predictive performance models, as well as a modular design that supports scalability across diverse deployment scenarios.
Future efforts will concentrate on refining the Stratus system from prototype level into a market-ready product, with enhancements to automation, third-party data integration, and field trials in diverse environments. Together, these technological innovations affirm the potential of Skytree's solutions to redefine CO2 capture technologies and align with global sustainability objectives