There are over 600 million people without access to electricity in Sub-Saharan Africa. The design of sustainable electricity systems needed to fuel development in the region requires context-specific power system modeling. Modeling data requirements however can be challenging for researchers and other stakeholders to access. To address this, an open-access cost optimization capacity expansion model, known as PROGRESS (Programmable Resource Optimization for Growth in Renewable Energy and Sustainable Systems), has been built to explore generation expansion pathways for countries with low availability and access to power systems data. The model has relatively low data requirements and is easily adaptable to enable comparative scenario analysis. This paper focuses on a first order proof-of-concept to show how PROGRESS works and then presents preliminary results for generation capacity expansion using the case of Kenya.