Nuclear energy produces more carbon-free electricity than any other source, accounting for ~20% of U.S. electricity generation. With the net-zero emission goals of the upcoming decades, there is a consensus and recognition of the vital importance in continual operation of existing reactor fleet. Over the last 25 years, the U.S. NRC has approved over 130 power-uprates for the existing fleet ranging from ~0.5-20%. Given that the rise of cheap natural gas has challenged the economic viability of adding new nuclear power plants, further exploration on increasing the value of the existing fleet is critical. An additional uprate of 50% to existing nuclear generation will mostly meet the carbon-free electricity needs of the next 10 years. In 2008, MIT and Westinghouse studied the feasibility of a 50% power uprate, and the major barriers to its adoption were the lack of availability for greater than 5% enriched fuel and uncertainty regarding feasible plant lifetimes to motivate the needed refurbishment investments. The advent of LEU+ (5-10% enrichment) and Accident Tolerant Fuels (ATFs) in a carbon-constrained economy as well as approval of an 80-year life by U.S. NRC for selected plants, provides an opportune time for revisiting the extend for an achievable power-uprate. This paper will outline and quantitatively support additional extended power-uprate for a generic PWR and BWR by leveraging LEU+ and ATF based on neutronics, thermal-hydraulics, fuel performance and economic assessments. The maximum allowable uprate is achieved by fuel geometry optimization while constraining the fuel materials to near term options (e.g., UO2/Zr). With adequate refurbishment of plant equipment, an economical 50% power uprate can be possible while shortening the fuel cycle to 12-month. A fleet-wide power uprate of such magnitude will not only enable meeting the U.S. emission-free electricity generation targets by 2030s, but it will also provide a much-needed bridge for advanced reactor deployment timelines and revitalizes U.S. utilities interest to invest in nuclear energy at a scale needed to achieve future net-zero targets.