CO₂ Capture Module

With the issue of global warming attracting public attention around the world, CO₂ emissions regulations are expected to be tightened into the future.
We have been working to reduce greenhouse gas emissions. In March 2023, we declared the “Scope1+2” Carbon Neutrality Challenge in 2030. We have been taking on challenges to develop CO₂ capture technology in addition to reducing CO₂ emissions. Here, we introduce our CO₂ capture module under development.

What is a CO₂ capture module?

The CO₂ capture module, which we are currently developing, separates and captures CO₂ directly from the atmosphere. This is one of the technologies that are referred to as direct air capture (DAC). The CO₂ concentration in the atmosphere is 0.04%, so CO₂ can be captured only in limited ways. We use a method using amine-based absorbers. After absorption, the absorbers are heated to increase the CO₂ concentration and release CO₂. After releasing CO₂, amines recover their absorption capacity. Thus, they can be used as absorbers repeatedly.

Features of our CO₂ capture module

Because amines are generally classified as hazardous materials, they are not suitable for outdoor use. Thus, the structure is designed to elicit the characteristics without exposing amines outside so that the CO₂ capture module can be used safely.
However, the conventional CO₂ capture method using amines incurred high energy costs due to heating to release CO₂. Namely, a large amount of energy was required to capture CO₂, resulting in additional CO₂ emissions. We are taking on the challenge of solving this conventional issue, based on an approach using a “solar thermal collection system.” Only heat is required, so the CO₂ capture module is directly heated by thermal energy created by collecting sunlight without using solar cells. A compact system can be realized because the energy efficiency is high compared to solar cells and no complicated mechanism is required. It can be used anywhere exposed to sunlight.

We are planning to create a cycle of capturing CO₂ at night and releasing CO₂ under the sun during the day. We are also developing a temperature control system because the heating temperature changes depending on the weather.

Future development

Most CO₂ capture systems are large in scale to pursue efficiency. Such systems cannot be easily introduced. There are complaints that it is difficult to work on carbon neutrality. We hope to realize a world where “anyone can readily participate in carbon neutral efforts” by using CO₂ capture systems that incorporate portable and compact CO₂ capture modules.
We completed prototypes of a compact CO₂ capture module and a solar thermal collection system and demonstrated their capability to capture CO₂. Despite issues to be solved, such as capture efficiency, we will continue to make improvements and achieve truly eco-friendly CO₂ capture.