The roughly two-hectare facility, still under construction, is hosting what could be called a carbon removal Olympics. It will pilot eight different versions of a similar technology using various machines that will suck in air, remove the carbon dioxide and send it to a central plant where it will be compressed and liquified for storage deep underground.
The winner of this initiative wouldn’t get a medal on a podium. Instead, Deep Sky, the Montreal-based project developer behind it, plans to take the best versions of the direct air capture technology that prove most effective in Canada’s climate and deploy them on a commercial scale all over the country.
“The EROI for discovering oil and gas in the US has decreased from more than 1000:1 in 1919 to 5:1 in the 2010s, and for production from about 25:1 in the 1970s to approximately 10:1 in 2007 (Guilford et al., 2011).”
https://www.sciencedirect.com/science/article/pii/S0301421513003856
Edit: from the same source.
An examination of the EROI literature on solar photovoltaic or PV energy generation shows differences in the assumptions and methodologies employed and the EROI values calculated. The values, assumptions, and parameters included are often ambiguous and differ from study to study, making comparisons between PV and other energy EROI values difficult and fraught with potential pitfalls. Nevertheless, we calculated the mean EROI value using data from 45 separate publications spanning several decades. These values resulted in a mean EROI value of roughly 10:1 (n of 79 from 45 publications) (see Lambert et al., 2012 for references) (Fig. 3). It should be noted that several recent studies that have broader boundaries give EROI values of 2 to 3:1 (Prieto and Hall, 2012, Palmer, 2013, Weissbach et al., 2013)