This paper aims to understand, develop and execute computational models to analyse the cost benefit of the use of different percentages of biodiesel in urban solid waste collection and to verify the biodiesel production viability by organisations. For the models' development, the system dynamics method was used. Mathematically, System Dynamics model is a system of linear equations. Through Vensim software, it was possible to develop, document, simulate, and analyse the models, noting the financial impact caused by waste collection in seven municipalities in southern Brazil. For the modelling, nine scenarios were developed and divided into 3 groups: simulation with different percentages of biodiesel, simulation using BIOBOT 20 processor, and simulation through a plant construction by the company. As a result, it was found that, in the long term, the best scenario for the company analysed is the use of BIOBOT 20 processor with 15% biodiesel percentage, followed by the construction of its own plant, also using 15% biodiesel. Results were satisfactory and met the designers' expectations.