This paper presents and evaluates a new approach of energy estimation for single software components based on program flowcharts. This estimation is designed to be applicable early in the design process, which enables system designer to evaluate different design variants with respect to the energy consumption of the later system. The energy estimation model is based on individual flowchart elements and execution probabilities for branches and iterations. The used flowchart elements are for arithmetical calculations, flow control and reads/writes, which are a selection of possible elements used to show the feasibility of the approach. The estimation model is verified in a first step by using three commercially available benchmarks. The flowcharts of these are utilized to estimate the energy consumption by using the presented model. The comparison between estimated and measured energy consumption of an exemplary embedded system results in an estimation error bandwidth between -11.9 % and +6.9 %. The main benefit of the presented approach is the applicability within the development phase "System Design" [1], i.e. previous to any software implementation. This is realized by using only available information of that development phase and generic elements to estimate the energy consumption.

Abstract-This paper presents and evaluates a new approach of modeling energy consumption of embedded systems resulted by concurrent software components. The objective is to enable energy estimation within early phases of system development, which allows system designers to compare different allocations of software components within networked systems.The model is presented in detail and its application demo started by a case study. Additionally, an execution time estimation for software components is presented which is necessary for the energy model -but previously not available. The model was developed being applicable early in the development process, i.e. previous to any software implementation. This was realized by using only available information.The The developed model was applied within an automotive case study which shows a theoretical energy saving potential of 36.2 %. This demonstrates the potential and relevance of modeling energy estimation within early development phases.Index Terms-Embedded systems, energy efficiency, energy estimation, networked embedded systems (automotive).