the transfer and usage of a modulated carrier signal within a power signal on a power line communication system is described . the modulated signal comprises metadata which is transmitted at a different frequency than the transmitted power . the metadata , including such elements as energy costs , providers , renewable source status and originating location , may be used by consumers to make subsequent purchasing decisions . additionally , the energy costs of any given computer node commonly distributed in a grid architecture may be collected by a workload dispatcher in order to make more accurate cost and energy source based dispatch decisions . the consumer may be able to communicate directly back to the power provider . the use of computer - readable medium and product containing instructions that are implemented on a computer is also covered . finally , the invention may be deployed on behalf of the consumer by a third party service provider .