The article analyzes cost-effective ways to reduce CO2 levels using a world energy model. It looks at how wind power, solar panels, and fuel-cell vehicles can help stabilize CO2 concentrations. The study shows the most efficient technological options for reaching CO2 levels of 550, 500, and 450 parts per million. It also examines how climate policies can drive technological changes and affect costs. The research finds that carbon capture and storage are important for reducing CO2, and that energy system costs may increase. Overall, the study highlights the impact of technological advancements on CO2 stabilization efforts.