This article presents an experimental mixed-methods study on the case of a winery located in Argentina. To this end, an architectural survey was carried out, as well as thermal monitoring with sensors in the winemaking facilities during pressing. Once the industry was described and temperature data was collected for the winemaking processes and the climate, a steady-state simulation model was built. After validation with real data, the model was used to simulate passive strategies for the winery's envelope and fermentation tank. Then, the energy demand savings resulting from the simulated passive strategies used for the thermal control of the winemaking process were estimated. The most effective passive strategies for reducing energy demand were defined quantitatively. A budget was drawn up for the construction of the strategies and a ten-year cash flow analysis was carried out for each. From this comprehensive analysis, the investment profitability indicators were obtained for each strategy: the Internal Rate of Return (IRR) and the Net Present Value (NPV). Subsequently, the data was complemented with the time required to recoup the investment, the payback period, measured in years. Finally, the economic-energy factors that affect the profitability of energy efficiency investments are analyzed for the case of the wine industry and the different implications of the payback period and the cash flow methodologies are shown.