For most countries around the world, sourcing energy entirely from wind, solar, geothermal, and hydropower by 2050 would reduce their energy needs and costs, improve air quality, and help slow climate change, according to a study in Environmental Science & Technology.
your article makes a claim unsubstatiated by the paper itself. and the paper is almost 2 decades old, and does not, itself, make any claim about the best way for anyone to reduce their GHGe.