WHAT WE DO

CO2 Removal & Storage with Microalgae

We permanently remove CO2 from the atmosphere by growing and burying microalgae.

 

Biomass Carbon Removal and Storage (BiCRS) combines photosynthesis with technology. ​Our outdoor photobioreactors create ideal conditions for the rapid growth of microalgae biomass in water using sunlight. Through photosynthesis, the algae bind CO2 from the atmosphere as a natural process. That’s why our BiCRS approach is energy- and cost-efficient.

Our Process

Photosynthesis in algae has been optimized over millions of years of evolution. We adapt this already highly efficient process and enhance it with technology for our approach to biomass carbon removal and storage (BiCRS). It involves three steps:

1. Growth

In our photobioreactors, algae grow by cell division. They thrive in natural light and are supplied with nutrients and CO2 from the atmosphere. During photosynthesis, the algae bind CO2 and the produced oxygen is released into the atmosphere.

2. Harvesting & Drying

As soon as the algae have reached a certain density, harvesting begins. Part of the biomass is continuously filtered from the water and dried. The dried biomass consists of more than 50% carbon.

3. Storage

The carbon-rich biomass is stored underground for the long term, e.g. in disused gravel pits or underground mines. Overall, the process has a negative CO2 balance and is therefore considered a negative emission technology.

Benefits of our Carbon Removal Solution

MEASURABLE

We weigh the biomass and measure its carbon content before we bury it. This allows us to determine exactly how much CO2 has been removed from the atmosphere. With 1 kg of algae biomass about 1.8 kg of CO2 can be removed.

PERMANENT

The composition of the dried biomass and suitable storage conditions, such as pH value and water content, ensure that it remains stable for over 1000 years. This means that the removed carbon is permanently locked away.

ENERGY-EFFICIENT

Sunlight is the main energy source in our approach. Therefore, we only need about 1.5 kWh of technical energy to bind 1 kg of CO2. We avoid transport or keep distances short by operating our bioreactors in the immediate area of the storage site.

ADDITIONAL

Our process verifiably removes additional CO2 from the atmosphere on your behalf. This avoids double counting of our CO2 removal certificates.

VERIFIABLE

We attach great importance to a high standard of monitoring, reporting and verification (MRV) to ensure transparency and verifiability of our process.

SCALABLE

Our photobioreactors enable the highly efficient production of biomass for CO2 sequestration. They are modular, scalable and plug & play ready for installation.

What are Negative Emission Technologies?

Negative emission technologies (NET) include technological approaches and strategies to remove carbon dioxide (CO2) and other greenhouse gases such as methane (CH4) from the atmosphere. By definition, more CO2 is removed than is emitted by the application of the technology. NETs therefore reduce the overall concentration of CO2 in the atmosphere and its impact on global warming.

 

The negative emission technology developed by Arrhenius is based on microalgae.

Why we need negative emissions

 

Negative emissions are not a substitute for drastically reducing greenhouse gas emissions! Avoiding CO2 at its source remains the most effective and urgent strategy to address climate change.

 

The transition to renewable energy and other non-fossil resources is progressing, but it will take time. Some emissions may not be reduced fast enough. In addition, there will always be CO2 emissions that are hard-to-abate or unavoidable, such as those from agriculture or waste incineration. These emissions can be tackled with negative emission technologies.

Biomass for Bioeconomy

Arrhenius photobioreactors provide precise control over operating parameters, ensuring fast and highly efficient biomass production. Our microalgal biomass is tailored for various applications within the bioeconomy. 

 

Replacement of fossil materials
Microalgal biomass can replace fossil raw materials in several industries. This improves the carbon balance by eliminating unnecessary emissions and reducing the overall CO2 footprint. Possible applications include the sustainable production of:  

 

  • Industrial goods (e.g. dyes, cosmetics or bioplastics) 
  • Fuels (e.g. biodiesel or bioethanol)
  • Agriculture fertilizer (e.g. biofertilizer) 
  • Platform chemicals (e.g. ethanol, glycerin) 

 

Avoid long distance transportation
In the food and animal feed industry, microalgae serve as a sustainable source of protein. For example, they can replace soy in animal feed. Unlike soy, which is often transported over long distances, microalgae can be produced locally with high efficiency. This further reduces the environmental impact.

Our Services

Arrhenius offers various services related to bioreactor design and microalgae production, as well as customized analyses:

-Conceptual design & implementation of feasibility studies 

-Life Cycle (Impact) Analyses (LC(I)A) 

-Techno-Economic Analyses (TEA) 

-Utility Analyses (UA) 

-Energy, mass and material balances 

-Ecological and economic calculations 

-Experimental investigations & validations at lab scale 

-Bioreactor design & development 

-Open and closed systems

-Artificially illuminated and outdoor photobioreactors

-Analytical Services

-Monitoring of key growth parameters

-Real-time biomass tracking

-Sample-based analyses of biomass composition and quality

-Microalgae biomass production 

-Inoculum production 

-Harvesting & drying techniques 

-Different extraction methods

(e.g. oil extraction with soxhlet process)

Our Infrastructure

  • Analytical Laboratory

    For studying the health of microalgae or laboratory-scale experiments.

  • 40 L Lotus Mini

    R&D prototype with artificial lighting for sun simulation, allowing indoor experiments at any time.

  • Greenhouse and Control Unit

    Fully automatic operation and remote control.

  • Seed Train

    In-house infrastructure for inoculum preparation and production for different algae strains.

  • 600 L Lotus 34

    Outdoor photobioreactor designed for increased microalgae productivity with minimal specific energy consumption.

  • 10 L Reactors

    10x10 L bubble-column bioreactor, artificially illuminated for lab-scale experiments or inoculum production.

  • 500 L LOOFAH

    Reactor design for maximum area specific productivity, artificially illuminated, closed system.

  • Harvesting Equipment

    Centrifuge adapted for very small microalgae (down to 2 to 10 μm in diameter).

Frequently Asked Questions

CO2 removal & negative emissions

Why do we need to remove CO2 from the atmosphere?

Why not just plant more trees?

Why not remove other greenhouse gases such as methane (CH4) or nitrous oxide (N2O)?

How much CO2 can be removed with algae biomass?

Why the name "Arrhenius"?

Algae & biomass storage for CO2 removal

What kind of algae do you use?

Are the algae toxic or harmful to the environment?

Why don't you just burn the algae?

How and where is the algae biomass stored?

Do you have more questions?