How to improve crop yields in controlled environment systems with Direct Air Capture

In today's competitive agricultural landscape, growers in controlled environments are constantly seeking ways to increase crop productivity and maximize greenhouse yield while keeping operational costs low. While CEA enables consistent, year-round production, its reliance on artificial inputs can also drive high energy costs.

A profitable CEA operation therefore depends on innovations that directly address these costs while supporting optimal productivity.

The challenge with traditional CO₂​ sourcing for greenhouse yield

For many crops, a critical challenge is the rapid depletion of CO₂​ inside a sealed environment. During peak photosynthetic activity when plants are absorbing the most CO₂, CO₂​ levels can drop as low as 200 ppm, a condition that has a more significant negative effect on plant growth than supplementation has a positive effect. This makes CO₂​ supplementation a necessity to prevent crop loss.

Traditionally, growers have relied on two primary methods for CO₂​ enrichment: combustion and compressed liquid CO₂ gas tanks. Combustion is common, but inefficient - growers often need CO2 when they do not need additional heat, forcing them to burn fuel unnecessarily. Combustion also carries the risk of introducing impurities like carbon monoxide and nitrogen oxides, which can severely damage plants.

Compressed or liquid CO₂​ tanks offer a purer source, but they depend on complex and unreliable supply chains and come with high, volatile costs.

Direct Air Capture: a resilient technology to improve crop yield

The limitations of conventional CO₂ sourcing methods have paved the way for an innovation in sustainable agriculture: Direct Air Capture (DAC). DAC extracts CO₂ directly from ambient air at any location, fundamentally transforming the CO₂ supply chain for CEA.

DAC technology uses chemical or physical processes to absorb atmospheric CO₂. The captured CO₂ is then released and purified, resulting in a concentrated stream that can be used for agricultural enrichment. DAC’s flexibility and independence from industrial plants or pipelines enables the creation of an on-site, localized CO₂ source. This makes it one of the most flexible agricultural practices to increase crop yields.

The strategic advantage for growers

DAC is more than a source of CO₂; it's a strategic asset that enhances the entire CEA business model:

Predictable and reliable supply: DAC eliminates dependence on external gas suppliers and long-distance deliveries that are vulnerable to supply chain disruptions. An on-site DAC system provides a high-quality, on-demand supply of CO₂, ensuring that the optimal CO₂ levels for plant growth can be maintained consistently.

Operational efficiency: DAC technology can be an integral part of a CEA facility's energy and resource management strategy. Many DAC systems require thermal energy to release captured CO₂, and this heat can be sourced from the facility itself. For example, the technology can repurpose heat from CHP or boiler systems. This creates a symbiotic relationship where heat is transformed into a valuable input for the DAC system. This circularity not only increases the energy efficiency of the entire operation, but also reduces the need for external heating, thereby lowering overall energy consumption and costs. DAC’s ability to operate flexibly when grid energy costs are low further enhances its integration into a smart energy management strategy.

The decarbonization advantage: As a carbon capture technology, DAC provides a different value than traditional methods by providing CO2 circularity. Rather than relying on fossil fuels for combustion or energy-intensive transport of fossil-based CO2, DAC captures CO2 directly from the air and reuses it. This is a critical market differentiator that also helps growers align with national sustainability targets and meet the increasing requirements of major retailers for sustainable produce.

Improving greenhouse payback period

Adopting technologies like DAC requires a comprehensive economic analysis that looks beyond a simple cost-per-unit calculation. The investment is justified by its long-term benefits and how it de-risks the business model, which directly contributes to greenhouse’s payback period and increased crop productivity.

The payback period includes:

• Reduced time to maturity, which allows for more harvests annually and faster revenue cycling

• Optimized operational costs, as DAC can leverage on-site heat and cold water to capture and purify CO₂, and can be turned on or off to match fluctuations in electricity prices

• Risk mitigation, as volatile energy prices and CO₂ supply chain vulnerabilities can impact a CEA operation’s profitability. By providing a stable, predictable on-site CO₂ source, DAC enables growers to respond flexibly to these volatilities, which enables more confident long-term planning.

The integrated future of CEA and DAC

A profitable future for CEA depends on resolving the tension between crop productivity, energy consumption, and CO₂ supply. Traditionally, CO₂ enrichment has forced growers to rely on fossil based sources tied to heating or CHP systems, often making them choose between maintaining optimal CO₂ levels and managing energy costs.

DAC changes this dynamic. By providing a high-purity, predictable, and on-demand source of CO₂, DAC gives growers more control- the ability to optimize yields, decouple from fossil CO₂ and optimize both energy use and costs.

Interested in learning more about how Direct Air Capture can impact the future of your greenhouse crop production? Reach out to our team of DAC experts for a detailed analysis of your specific case and how DAC can support your operations.