Study Finds Renewables Offer Greater Climate Value Than Direct Air Capture in Most U.S. Regions

Investment in renewable energy is likely to deliver greater climate and public health benefits than direct air capture in most U.S. regions, according to a new peer-reviewed study published in Communications Sustainability.

The study, titled “Direct air capture has substantial health and climate opportunity costs”, compares direct air capture, or DAC, with utility-scale solar and onshore wind across 22 electricity grid regions in the United States between 2020 and 2050. It was published on 4 May 2026 and led by researchers including Yannai Kashtan, Jonathan J. Buonocore and colleagues from PSE Healthy Energy, Boston University School of Public Health and other institutions.

The research asks a practical policy question: if a fixed amount of capital is available for climate mitigation, does it produce more benefit when spent on DAC or on renewable electricity? The answer, in most cases, is renewable energy.

What the Study Found

The authors found that renewable energy deployment delivers greater combined climate and health benefits than direct air capture across nearly all modelled scenarios and regions. DAC only approached cost-effectiveness under highly optimistic assumptions about future technological breakthroughs.

The comparison is important because many earlier assessments looked at whether DAC could remove more carbon dioxide than it emitted, or whether it could eventually meet specific cost thresholds. This study instead evaluates DAC against alternative uses of the same capital, with wind and solar used as the benchmark.

In the study, the researchers modelled the effect of spending the equivalent of $100 million per year, in 2024 dollars, on different climate mitigation options. They assessed the resulting greenhouse gas impacts, air pollution effects and public health outcomes using established grid and health impact models.

Why Direct Air Capture Faces a Cost Challenge

Direct air capture removes carbon dioxide directly from ambient air using chemical solvents or sorbents. The captured CO₂ is then released through heat or pressure changes before being transported for storage or use. Because Wind power and climate mitigation is highly diluted in the atmosphere, DAC systems require substantial energy input, making the technology expensive and energy-intensive.

The Sustainability Online summary notes that current DAC costs are around $1,000 per tonne of CO₂ removed, with energy requirements of about 5,500 kilowatt-hours per tonne. The study also considers more optimistic scenarios in which energy use and costs fall significantly, potentially to 800 kWh and $100 per tonne in a breakthrough case.

Even under more advanced DAC assumptions, however, renewables often remain more beneficial per dollar invested. The study found that under an “advanced efficiency improvement” scenario, DAC could become modestly beneficial, but solar and wind still produced several-fold higher benefits.

Health Benefits Strengthen the Case for Renewables

A key feature of the study is that it includes public health impacts, not just greenhouse gas accounting. Wind and solar can reduce emissions by displacing fossil fuel generation on the grid. That can cut both carbon dioxide and air pollutants linked to respiratory and cardiovascular harm.

DAC does not directly reduce conventional air pollution. If a DAC facility draws power from a grid that still includes fossil fuel generation, its electricity demand can increase emissions of air pollutants from power plants. The Nature paper states that, under the current commercial performance scenario, grid-connected DAC would have a net negative impact through 2050, producing more greenhouse gas emissions and air pollution-related health harms than it prevents through carbon sequestration.

This is a significant finding for policymakers, utilities and corporate buyers of carbon removal credits. It suggests that the source of energy used to power DAC is central to its climate and health performance.

Regional Differences Matter

The study does not conclude that DAC is never useful. Instead, it shows that its relative value depends on technology costs, energy efficiency, grid mix and geography.

Across the United States, renewable energy generally performed better than DAC in the researchers’ models. Only in the most optimistic DAC breakthrough scenario did grid-connected DAC modestly outperform renewables at a national level. Even then, wind and solar continued to outperform DAC in some regions, including parts of the Upper Midwest.

This regional variation matters because grid emissions, renewable resource quality and public health impacts differ across electricity markets. A DAC project powered by clean electricity in one region may have a very different impact from a similar project connected to a more fossil-heavy grid elsewhere.

Implications for Net-Zero Strategies

For companies developing net-zero plans, the study reinforces the need to prioritise direct emissions cuts before relying heavily on atmospheric carbon removal. Renewable electricity procurement, electrification, efficiency improvements and fossil fuel displacement can often deliver immediate emissions reductions while also improving air quality.

DAC may still have a role in addressing residual emissions from sectors where full decarbonization is technically difficult or costly, such as aviation, cement, chemicals or agriculture. It may also be important for removing legacy emissions after global emissions have been reduced close to zero.

However, the study warns against treating DAC as interchangeable with emissions reduction. When climate finance, clean electricity and project development capacity are limited, using those resources for DAC can carry an opportunity cost if the same investment would have delivered greater climate and health benefits through renewables.

A Caution for Carbon Removal Policy

Governments are increasingly supporting carbon removal through tax credits, grants, procurement programmes and innovation funding. The study suggests that such policies should be designed carefully to avoid diverting resources from cheaper and more immediate mitigation options.

For investors, the findings underline the importance of comparing DAC projects not only against their own cost per tonne, but also against alternative decarbonization investments. A project can be carbon negative and still be a weaker use of capital if another option reduces more climate damage and health harm for the same cost.

For grid operators and energy planners, the findings also raise a practical question: should clean electricity be used to power DAC, or should it first be used to replace fossil fuel generation? In many current grid conditions, the study suggests the latter may deliver greater near-term benefits.

Carbon Removal Remains Relevant, but Timing is Critical

The study’s conclusion is not that direct air capture should be abandoned. Rather, it argues that DAC should be evaluated within the broader portfolio of climate mitigation options. Its highest-value role may come later in the transition, once clean electricity is abundant, fossil fuel generation has been largely displaced, and residual emissions remain difficult to eliminate.

Until then, the research indicates that solar and wind deployment often provide a stronger climate investment case. For industries and policymakers focused on near-term emissions reductions, the message is clear: carbon removal can complement decarbonization, but it should not delay or displace proven renewable energy deployment.

Source: sustainabilityonline.net