Capturing CO2 from the air is hard. Why else would no fully commercial systems be in operation?

We do it for nitrogen. We’ve known how for over 100 years, and its conversion into fertilizer has transformed agriculture. The concentration of CO2 in air is about 1000 times less than that of nitrogen, which essentially means much more energy is required to extract it. Carbon dioxide removal from the air was originally developed in the space sector, where confined to a tin can floating in space, CO2 exhaled by astronauts had nowhere to go and had to be extracted if the crew were to last more than about 3 hours.

At Skytree, we employ a material originally developed in the late 1990’s for a European Space Agency life-support system. Its base is polystyrene and on its surface lay molecular groups with the opposite charge to the CO2 molecule (which has a negative charge associated with its oxygen atom). The basis for the capture is the Van de Waals force (its namesake is a Dutch scientist who discovered the force in the 1800s), where the CO2 molecules are attracted to the molecular groups on the material’s surface through electrostatic bonding.

The material represents the cutting edge of CO2 removal from the air in terms of its performance, energy requirement and stability. Nevertheless, as part of our company mission and despite our ability to modify it to improve its performance for our applications, Skytree is on the hunt for even better materials and processes. As such, we collaborate with academia and the corporate world alike to scout the market for new solutions and together invent our own.

Here are a few examples of our collaborations

University of Swansea – Dr. Enrico Andreoli, after receiving funding to develop ways of decarbonizing Welsh industry under a program called RICE (Reducing Industrial Carbon Emissions), is collaborating with Skytree to test a novel mineral based material.

Fraunhofer Institute – The Institute has discovered a novel membrane design with dramatically improved efficiency to separate gaseous CO2. Fraunhofer lent us their invention to test in our own processes.

Corporate world – We work with a Cambridge university spin-out which has developed a way to manufacture synthetic materials with a bespoke design depending on the gas in question which needs to be filtered. They are able to provide 70,000 variations on their material depending on the needs of the client. We are currently testing their MOF materials for application to the automotive industry.

In 2018, Skytree partnered with Sogefi in order to develop a prototype that could demonstrate the removal of CO2 & humidity from a car cabin. The unit is intended to drastically reduce the power consumption of HVAC systems in cars by fully recirculating the cabin air. An added benefit will be the reduction of pollution that enters a car cabin. The project was desired by Sogefi in order to meet its strategic objectives which includes transitioning towards the EV market. Over the 12 month project duration, Skytree was responsible for the following elements:

• Coordination of two project teams (15 people) between two countries
• Electronics and data-acquisition
• Simulation
• Rapid prototyping
• Assembly and verification
• Performance testing
• Project reporting

The project culminated in the demonstration of the unit in a Tesla Model X. Two versions of Ersa are now available for demonstration at OEMs. Sogefi & Skytree have since kicked off a follow-on project to develop a smaller, more energy efficient version of the product.