The major concern with the environment, linked to economic growth, becoming more competitive in the world's energy challenge. It is in this view that the choice of investment for biodiesel production should meet the financial aspects of the
operation, ensure the profitability of the investment, as well as the applicants environmental and ecological aspects of the decision to implement the chosen design. In this work a methodology for economic analysis and comparison between
different processes of biodiesel needed in choosing an investment oriented benefits to the environment has been developed. Although methods for analyzing investments
are actually valid, these have been left alone for much of the business community, especially small and medium enterprises. First, because the introduction of these methods in the curricula of faculties is a relatively recent development. Second, because in many cases, entrepreneurs use and sometimes misuse of intuition and experience when making decisions on the application of capital. We used two
financial data from two different processes, involving the production of biodiesel using castor oil and waste frying oil as basic inputs. The proposed method performs complex calculations involving optimization of financial conditions, which become simple when using a spreadsheet. Developed a method of combining simultaneous analysis techniques net present value (NPV) and internal rate of return (IRR), the
practicality of using Solver tool available in Excel® spreadsheet. It also presents essential features to attract the vast majority of small and medium entrepreneurs due
to the mathematical complexity of little use and availability in most enterprise installations.
