This legislation amends the Farm Security and Rural Investment Act of 2002 to significantly enhance support for the development and manufacturing of advanced biofuels, renewable chemicals, and biobased products. It broadens the scope of eligible activities to specifically include ultra-low-carbon and zero-carbon bioethanol, aiming to foster innovation in sustainable energy and product creation. The bill also refines the definition of eligible projects by removing the "technologically new" requirement and explicitly adding renewable chemicals and biobased products to the list of end-user products. A key provision of the bill is the establishment of a new competitive grant program , available on a year-round basis, to fund the development, construction, or retrofitting of pilot or demonstration-scale biorefineries. These grants are intended to help prove the commercial viability of processes that convert renewable biomass into advanced biofuels, renewable chemicals, and biobased products. For both the new grants and existing loan guarantees, the Secretary may waive the requirement for an independent feasibility study if the technologies are proven or commercially available. The new grant program includes a priority scoring system for applications, considering factors such as market potential, financial participation, innovative feedstock use, environmental impact, and rural economic development. Grants are capped at 60 percent of the project cost, with the non-Federal share allowing for material contributions. Additionally, the bill modifies the maximum amount for loan guarantees to 10 percent of the total annual funding and extends the authorization of appropriations for both loan guarantees and grants, allocating $40,000,000 annually for fiscal years 2025 through 2029.