Flameless calcination, where a heat transfer fluid is used to provide heat for the calcination reaction to a mineral feed material may reduce direct carbon dioxide emissions during calcination by 50%. Concentrated solar power (CSP) and high temperature reactors (HTRs) are low-carbon emitting energy sources suitable for flameless calcination. This work provides a brief economic evaluation of flameless phosphate rock calcination with CSP/HTRs as heat sources. The economic evaluation consists of cost comparisons against gas-fired kilns and economic feasibility calculations based on the net present value method. The flameless system with CSP/HTRs is currently not cost-competitive. Anticipated cost reductions and higher natural gas prices may, however, change this outcome in the future. For the flameless system to be competitive low-interest rates (5-10%) and higher natural gas prices (7.5-10 US$/mmBTU) need to be present Although the flameless system with CSP/HTRs is presently not cost-competitive it can be economically viable given low-interest rates (<= 5%) and higher end heat selling prices (>= 45 US$/MWhth). (C) 2017 Elsevier Ltd. All rights reserved.