Renewable energy more cost effective than direct air capture

Investment in renewable energy delivers more cost-effective and positive environmental outcomes than direct air capture, when it comes to reducing carbon, a new study led by PSE Healthy Energy has found.

According to the study, Direct air capture has substantial health and climate opportunity costs, which was published in Communications Sustainability, the case for investing in direct air capture ‘weakens substantially’ when compared to solar and wind.

The study was undertaken alongside researchers at Boston University School of Public Health and the Harvard T.H. Chan School of Public Health, and evaluates the potential impact of direct air capture, compared to that of utility-scale solar and onshore wind across 22 electricity grid regions in the United States between 2020 and 2050.

Direct air capture

While previous analysis assessed whether direct air capture removes more carbon than it emits or whether it meets cost thresholds, this research compares the technology directly with alternative investment opportunities, in this case renewables.

“Our study underscores that being carbon negative isn’t enough to make direct air capture a good investment,” commented Dr. Yannai Kashtan, lead author and air quality scientist at PSE Healthy Energy.

At present, direct air capture costs around $1,000 per tonne of carbon dioxide removed, requiring around 5,500 kilowatt-hours of energy, however, in time, energy use and associated costs could fall significantly – potentially as low as 800 kWh and $100 per tonne.

However, even in this scenario, the researchers noted that renewables still provide greater climate and health benefits per dollar spent. Only under the most optimistic scenario did direct air capture outperform renewables at a national US level, however in some regions, such as the upper Midwest, wind and solar continue to outperform.

‘Variety of interventions’

“There’s a rapidly growing variety of interventions out there to mitigate greenhouse gases, and potentially affect public health as well,” commented Dr. Jonathan J. Buonocore, senior author and assistant professor of environmental health at Boston University School of Public Health and the Institute for Global Sustainability.

“Our research here shows the power of cost-effectiveness analysis to ensure that capital invested in climate mitigation has the most ‘bang for the buck’ for the climate, while having the fewest side effects.” Read more here.