This work developed a methodology and an associated calculation platform in order to identify the economic efficient design solutions for residential Net Zero Energy Building (NZEB) design considering the influence of the local climate, the endogenous energy resources and the local economic conditions. One case study of a detached house for 3 climates was analyzed with the tool developed in order to gain insights on the economic space of NZEB solutions and the influence of the climatic context. A methodology for assisting the choice of economically efficient NZEB solutions from the early design stage is now available. Its use in practice may be of great relevance as the results showed that the differences between an economically efficient and economically inefficient NZEB can be over three times both in terms of initial and life cycle cost. (C) 2012 Elsevier B.V. All rights reserved.