Abstract: Tongwei County has superior wind and solar resources, but its power grid carrying capacity is severely insufficient, making it a Red Area for distributed PV integration. This paper examines the carrying capacity of county grid under the high proportion of renewable energy integrations, analyzes its current status and constraint mechanisms caused by spatiotemporal source-load mismatch. It proposes a renewable energy development sequencing and grid integration plan coordinated with grid upgrades, regulation capability construction, and load growth, transforming carrying capacity from safety constraints into order parameters. This provides theoretical support and practical pathways for building a safe, economical, and green county-level new type power system in Tongwei County and similar regions.