Electrochemical Nickel Battery System Reduces Energy Intensity of Direct Air Capture to 0.83 MWh per Tonne

Electrochemical Approach Displaces Thermal-Intensive DAC Methods

Direct air capture (DAC) technology has long faced a critical economic barrier: the energy intensity of separating captured CO2 from absorbent materials. Conventional systems rely on repeated thermal cycling, heating to release CO2, then cooling to reset the material, a process that consumes substantial electricity and undermines the business case for large-scale deployment. Researchers at the University of Delaware and RepAir DAC Ltd. have now demonstrated an alternative pathway using electrochemical separation, achieving energy consumption of 0.83 MWh per tonne of CO2 captured.

The innovation replaces thermal regeneration with electrical charge cycles. The system employs a battery-like architecture with two nickel hydroxide electrodes separated by an ion-permeable membrane. When electricity is applied, electrochemical reactions capture atmospheric CO2 and subsequently release it in concentrated form for collection or utilisation. This eliminates the energy-intensive heating and cooling loops that characterise conventional DAC installations.

Cost and Operational Implications for Industrial Deployment

The energy intensity metric is critical for investors and operators evaluating DAC viability. At 0.83 MWh per tonne, the electrochemical system operates substantially below many thermal DAC variants, which typically consume 1.5 to 2.5 MWh per tonne depending on sorbent type and operating conditions. This reduction directly improves the cost structure when renewable electricity is available at competitive rates.

For industrial operators in Spain and Portugal, the implication is straightforward: coupling this technology with on-site solar or wind generation, increasingly feasible given Iberian renewable capacity, can lower the effective cost of CO2 removal. This matters for hard-to-abate sectors such as cement, steel, and chemicals, where EU ETS compliance costs are rising and direct capture may become economically justified as an alternative to purchasing emission allowances at higher prices.

The electrochemical design also offers operational advantages. Absence of thermal cycling reduces material degradation and maintenance intervals, lowering capital replacement costs over the asset lifetime. The system's compatibility with renewable electricity sources aligns with EU climate policy objectives and reduces exposure to fossil fuel price volatility.

Regulatory and Market Context

This development arrives as EU carbon pricing continues to tighten. The EU ETS free-allocation phase-out accelerates through 2026, forcing energy-intensive industries to purchase allowances at market rates. Current ETS prices hover around €80–90 per tonne of CO2, creating a price floor below which DAC becomes economically uncompetitive. At 0.83 MWh per tonne and renewable electricity costs of €30–50 per MWh, the direct energy cost of capture falls to €25–40 per tonne, undercutting allowance prices and justifying investment in removal capacity.

Spain and Portugal benefit from substantial renewable generation capacity and access to EU decarbonisation funding through the Recovery and Resilience Facility and Horizon Europe programmes. Industrial operators should monitor whether this electrochemical DAC technology qualifies for co-financing under national decarbonisation schemes or EU innovation funding.

Strategic Monitoring Points

Operators and investors should track three developments. First, the transition from laboratory prototype to pilot-scale deployment: RepAir DAC's next phase will reveal whether the 0.83 MWh figure holds under continuous industrial operation. Second, the availability of nickel supply and cost stability, given current volatility in battery-grade nickel markets. Third, regulatory recognition of DAC as a compliance pathway under EU ETS rules and national carbon accounting frameworks, which remains uncertain and will determine whether captured CO2 can be monetised or credited against emissions obligations.