Direct Air Capture: Assessing Impacts to Enable Responsible Scaling

Responsible Scaling and Equitably Distributing Benefits

Responsibly Scaling DAC

The process that determines DAC siting will, in part, decide who is impacted, positively or negatively. Opinions diverge on whether next-generation technologies like DAC will provide meaningful benefits for communities (White House 2021a; Batres et al. 2021), but the early DAC projects assessments for social and environmental impacts and benefits to communities will be essential to determining whether DAC will gain a “social license to operate” (Gunningham et al. 2004).

Since any climate intervention involving new infrastructure will have both positive and negative impacts, decision-makers and other stakeholders must understand the balance of those impacts and associated trade-offs. For example, although solar PV has drawbacks related to mining and disposal that need to be mitigated and managed, it is broadly accepted as a critical technology for decarbonization with net benefits.9 For DAC to be responsibly deployed at scale, thorough life-cycle analysis of its environmental and social impacts is needed on a project-by-project basis (Batres et al. 2021), along with identification of ways to minimize negative impacts.

Historically, building new infrastructure has not considered impacts holistically—for example, externalities of energy technologies such as water use and damage to culturally important sites have received less attention than air pollution and greenhouse gas emissions (Gies 2017). DAC’s nascency presents an opportunity to better understand and communicate potential impacts and cobenefits and prioritize inclusive decision-making.

We recognize that this approach can require effort, consideration, resources, and time, even as threats from climate change grow more urgent. However, it can lay the foundation for long-term success by establishing a shared understanding of project goals and parameters that allows for more efficient execution and helps avoid project delays due to community concern—a common result of late-stage community engagement.

Equitably Distributing Benefits

One critical aspect that will determine the equity and long-term viability of DAC scale-up is the assurance of benefits to communities where DAC plants and infrastructure are sited. There is an opportunity for DAC scale-up to not only remove CO2 from the air but to offer benefits to communities and workers. Benefits could include high-paying jobs and training, local investment in CO2 utilization, or potential financial benefits to owners of pore space where captured CO2 is sequestered. DAC will likely be able to provide additional benefits to communities, but more research is needed to assess the types and magnitude of these benefits as more DAC plants are built and communities negotiate desired project benefits.

An assessment by the Rhodium Group (Larsen et al. 2020) estimates that 3,428 jobs (full-time, part-time, and seasonal) would be generated from building and operating a megaton-scale DAC plant. More than 3,000 of these are associated with plant investment, including equipment manufacturing, construction, engineering, and steel and cement manufacturing. The remainder are in plant operations, of which 278 are expected to be on-site for operations and maintenance. For context, there are 380 manufacturing jobs per establishment in the U.S. automobile industry, and an average of 46 and 28 jobs per generation facility in U.S. fossil fuel and geothermal electric power generation, respectively (BLS 2021). DAC operations jobs would be expected to last the lifetime of the plant, which is generally assumed to be 20 years (Fasihi et al. 2019), with high annual salaries expected, between $50,000 and $140,000, varying by industry (Larsen et al. 2020). If DAC plants are built continuously, jobs associated with plant investment could also be stable over time.

Residents of communities where DAC plants are sited could be employed in operations and maintenance and construction jobs, provided they receive skills training to fill these positions. Additional jobs would be created if captured CO2 is stored or used locally. Other jobs, such as engineering, will probably not be on-site.

For DAC-related employment to benefit communities, jobs should pay at least family-sustaining wages, provide benefits such as health care and retirement, a safe and supportive work environment, and opportunities for career advancement and skill-building (Brett and Woelfel 2016).10 Once DAC reaches a large enough scale to offer widespread and long-term employment, job training programs with guaranteed employment could help ensure that local workers have the skills necessary to benefit from DAC-related job creation (Urban Sustainability Directors Network 2021). The construction and operation of DAC plants could engage workers from existing unions, offering the opportunity for collective bargaining.

A potential benefit could also come from pore space royalties, or payments to landowners where CO2 is geologically stored. While there are ongoing legal debates about pore space ownership and rights are inconsistently applied in the United States, communities above or within a certain proximity of pore space or a monitored CO2 plume could receive benefits. There is precedent for this in the oil and gas sector, where land and mineral rights are leased to oil and gas companies that pay royalties as high as 25 percent of their revenues (Gentile 2015). However, royalties to large landowners could inequitably exclude marginalized communities from benefiting, and inconsistent or unclear pore space rights cannot ensure smaller landowners are protected. Thus federal, state, and local governments should establish a framework that can assess who has rights to pore space, who might be affected by CO2 injection, and how to equitably disburse benefits to affected parties (Johnson 2020).

A summary of environmental and social impacts of DAC is provided in Table 5.

Table 5 | Summary of DAC Impacts

Local impacts (environmental, social)

Magnitude of impact for 0.5 GtCO2/yr DAC

Opportunity to manage impact through project design (straightforward, moderate, difficult)

Construction-related impactsa (e.g., noise, particulate matter, influx of construction workers) (environmental, social)

Comparable to other types of infrastructure construction

Straightforward/Moderate

Visibility of facility, operational noise (environmental, social)

Dependent on project design and location in relation to people

Moderate

Increased traffic (environmental, social)

Dependent on project location; may be higher for solvent plants, which require more frequent addition of makeup solvent and calcium carbonate

Straightforward/Moderate

Energy demand to power DAC plants (environmental, social)

<5% of U.S. primary energy supply

Moderate/Difficult

Natural gas use for solvent plants (environmental, social)

Emissions of GHGs and nitrogen oxides (NOx) at much lower rates than natural gas plants without carbon capture

Straightforward (for sorbent plants that don’t need to use natural gas today)

Difficult for solvent plants that use natural gas today

Land use: DAC plant (environmental, social)

200 km2 for solvent plant

250 km2 for sorbent plant

Moderate

Land use: energy source (environmental, social)

Variable depending on energy source: up to 33,000 km2 for wind or 17,000 km2 for solar, though both can be colocated with other land uses

Moderate/Difficult

Solvent and sorbent use (environmental)

On-site drift losses of solvents at 10 percent of regulated limit; no expected on-site impact of sorbent use

Moderate for solvents

Straightforward for sorbents

Water use (environmental, social)

0–9 t H2O/tCO2 used for solvent plants depending on solvent concentration and local climate

1.6 t H2O/tCO2 used for steam regeneration sorbent plants, or up to 2 t water/ tCO2produced for indirect heating regeneration

Straightforward/Moderate

Job creation (social)

278 expected jobs on-site for operations and maintenance for each Mt-scale plant,

139,000 jobs at a 0.5 Gt scale

Moderate

Job training (social)

Dependent on federal initiatives and negotiated benefit agreements

Moderate

Pore space royalties (social)

Precedent in the fossil fuel industry, but has not yet been demonstrated for DAC

Difficult

Additional community benefits possible via community benefit agreement

Dependent on negotiations between developer and community

Moderate

Distributed impacts (environmental, social)

Magnitude of impact for 0.5 GtCO2/yr DAC

Opportunity to manage impact through project design (straightforward, moderate, difficult)

Reduction of atmospheric CO2(environmental, social)

0.5 Gt scale DAC would result in a 63% increase over carbon removal by U.S. lands in 2019 (U.S. EPA 2021)

Moderate

Natural gas extraction and transportation (for plants powered with natural gas) (environmental, social)

Methane leakage rates depending on location, but average 2.3% in the United States; other environmental impacts are variable

Social impacts are variable

Straightforward (for sorbent plants that don’t need to use natural gas today)

Difficult for solvent plants that use natural gas today

Solvent and sorbent production (environmental)

Up to 37% increase in global ethanolamine production for sorbent manufacture; 19% increase in global KOH production for solvent manufacture (assuming scale-up is half solvent and half sorbent systems)

Moderate for sorbent

Straightforward for solvent

Construction materials’ production and transport (environmental)

1–3% increase in annual production of cement and steel, up to 8% increase in annual PVC production

Straightforward/moderate; increase is incremental for most materials, but environmental impacts need to be managed

Energy infrastructure (environmental)

Dependent on energy source build-out and location

Moderate

Job creation (social)

More than 3,000 expected jobs in equipment manufacturing, construction, engineering, and steel and cement manufacturing

Moderate

Job training (social)

Variable

Moderate

Notes: GtCO2/yr = Billion tonnes of carbon dioxide per year; GHGs = Greenhouse gases; NOx = Nitrogen oxides; km2 = Square kilometers; H2O = Water; Mt = Million tonnes; t = tonnes; KOH = Potassium hydroxide; PVC = Polyvinyl chloride.

a Construction impacts are expected to be one time at each DAC site; other impacts are expected to be continuous.

Sources: Authors; primary sources in each section.

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