In a Denver suburb, an oil drilling rig plumbs the earth near a wealthy enclave framed by snow-capped mountains. The site is quieter, cleaner and less visible than similar oil and gas operations. It might just be the future of drilling in the United States.

Oil firm Civitas Resources designed the operation to run largely on the city's electric grid, eliminating daily runs by more than a dozen diesel fuel trucks. The electric rig has none of the soot or sulfur smell of diesel exhaust and is muffled enough that rig hands can converse without yelling.

As investors and lawmakers push the oil industry to lower its carbon emissions, this drill site and others run by Civitas offer one model for drillers looking to migrate to low- or no-carbon emissions operations.