<p>Biochar and bioenergy crop cultivation with carbon capture and storage (BECCS) are two major negative emission technologies for carbon dioxide removal (CDR). However, biochar production is limited by biomass supply, while BECCS depends on costly CCS infrastructure and faces storage constraints. Here, a novel combination of biochar with biomass supply from dedicated bioenergy crops (BCBE) is proposed to overcome their respective limitations. Through retrofitting current biomass power plants in China with pyrolysis systems or CCS, biomass power plants are assumed to use either residues from agriculture and forestry or from dedicated bioenergy crops on abandoned croplands to meet their capacity for biochar production. Based on these plants, the CDR potential and the economic cost of BCBE are first investigated by considering different components in the life cycle of biochar, and are compared with an alternative scenario using bioenergy crops supply for BECCS. Locations for building new pyrolysis plants are then identified and the achievable CDR under biomass utilization scenarios is estimated. With 73% agricultural and half forestry residues or 84% bioenergy crops supplied to plants, the CDR potential of BCBE is 25.8 Tg CO₂ year⁻¹ (95% CI: 23.6–32.4 Tg CO₂ year⁻¹), comparable to that of biochar derived from agricultural and forestry residues (29.8 Tg CO₂ year⁻¹, 95% CI: 28.2–36.8 Tg CO₂ year⁻¹). Despite the lower CDR potential of BCBE compared with BECCS, the cost of BCBE ($9.6 t⁻¹ CO₂) is much lower than that of BECCS ($90.9 t⁻¹ CO₂). With newly built pyrolysis plants supplied with bioenergy crops and agricultural and forestry residues, the maximum CDR of all biochar sources can reach 1880.4 Tg CO₂ year⁻¹. Thus, deploying biochar on a large scale with additional biomass supply from bioenergy crops is expected to contribute substantially to achieving China's carbon neutrality goal. However, critical uncertainties remain regarding plant retrofit feasibility, technology integration, and the biomass supply chain.</p>