This paper investigates the effect of artificially synthesized C–S–H accelerators (CAs) on concrete properties and analyzes their potential advantages for the precast concrete industry. The study found that adding CAs improves the workability of concrete while also significantly boosting its early compressive strength (particularly within 24 h). This characteristic showcases the dual-effect nature of CAs as additives. Notably, adding 1.5 wt% (relative to the weight of cement) CAs may boost the 6-h strength of concrete to 16.6 N/mm², meeting the conditions for demolding. This could allow precast concrete plant molds to complete four turnovers within 24 h, thus improving production capacity. Importantly, using CAs may eliminate the need for heat curing during production, thereby reducing the carbon footprint and energy use in the manufacture of precast concrete.