Checking Dust to Dust’s Assumptions about the Prius and the Hummer: Fact-checking using the GREET life cycle model underlines the deep divide between the Dust to Dust study and all previous scientific work

The Rocky Mountain Institute (RMI) conducted a life cycle analysis (LCA) using the Argonne National Laboratories' GREET model to evaluate the environmental impacts of the Toyota Prius and the Hummer H3. RMI tested four scenarios, manipulating vehicle lifespan and assembly energy requirements to see if the conclusions of a CNW Research/Marketing report—which claimed the Prius was more harmful to the environment—could be replicated. RMI found that the Prius consistently has a lower environmental impact in terms of greenhouse gas emissions and energy consumption, regardless of whether assembly energy for the Prius was tripled or if the Hummer was assigned a longer lifespan (207,000 miles) compared to the Prius (109,000 miles). The report concludes that vehicle operation dominates emissions due to the Hummer's poor fuel economy, and that the CNW findings diverge significantly from scientifically reviewed work.

• The Toyota Prius maintains a lower environmental impact than the Hummer H3 across all tested scenarios, including those designed to favor the Hummer. Even when the Prius's assembly energy requirements were tripled, it emitted fewer greenhouse gases than the Hummer in all lifecycle stages.
• Vehicle operation is the primary driver of greenhouse gas emissions for the Hummer H3, outweighing the impacts of mining and manufacture due to the vehicle's low fuel economy.
• Applying the lifespan assumptions used by CNW (207,000 miles for the Hummer and 109,000 miles for the Prius) causes per-mile emissions to converge, but the Prius still performs better. Furthermore, these assumptions make the Hummer's total lifetime energy and greenhouse gas emissions appear even worse.
• The findings of the CNW 'Dust to Dust' report are inconsistent with the GREET model and other scientifically reviewed and accepted life cycle analyses of hybrid vehicles.

APA

Hauenstein, H., & Schewel, L. (n.d.). Checking Dust to Dust’s Assumptions about the Prius and the Hummer: Fact-checking using the GREET life cycle model underlines the deep divide between the Dust to Dust study and all previous scientific work. RMI. https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T07-01_DustToDust.pdf

Chicago

Hauenstein, Heidi, and Laura Schewel. Checking Dust to Dust’s Assumptions about the Prius and the Hummer: Fact-checking using the GREET life cycle model underlines the deep divide between the Dust to Dust study and all previous scientific work. RMI, n.d. https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T07-01_DustToDust.pdf.

Wikipedia

{{cite report |last1=Hauenstein |first1=Heidi |last2=Schewel |first2=Laura |title=Checking Dust to Dust’s Assumptions about the Prius and the Hummer: Fact-checking using the GREET life cycle model underlines the deep divide between the Dust to Dust study and all previous scientific work |publisher=RMI |url=https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T07-01_DustToDust.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{hauensteinndchecking, author = {Hauenstein, Heidi and Schewel, Laura}, title = {{Checking Dust to Dust’s Assumptions about the Prius and the Hummer: Fact-checking using the GREET life cycle model underlines the deep divide between the Dust to Dust study and all previous scientific work}}, institution = {RMI}, url = {https://rmi.org/app/uploads/2017/05/RMI_Document_Repository_Public-Reprts_T07-01_DustToDust.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }