Currently most of the energy production is supported by fossil fuels, however, renewable sources contribution on worldwide demand of energy has been in constantly growth. One of the main challenges in the use of solar thermal energy in industrial processes is their cost, especially when is compared to energy generation by fossil fuels. This cost delimits the investment payback time for a thermo-solar installation to be feasible. This fact makes crucial the development of methodologies for the integration of solar energy for large-scale industrial applications. This work deals with the thermo-economic evaluation of the heat and power production through a low-temperature flat-plate solar collector system. Also, strategies were developed to increase energy efficiency by evaluating different process integration scenarios. The proposed strategies for energy efficiency combined with renewable energy were applied to an integrated solar thermal energy system into a 1G and 2G (first and second generation) bioethanol process from sugarcane. It was found that to replace the fully process heat and power with low-temperature solar thermal energy, a heat recovery network ? ?? ?????? of 5 °C, a heat duty of 131 kW and a supply temperature of 105 °C are required. All these results lead to a cost of 0.2112 USD/kWh of the integrated system. The power system operates independently by mean an Organic Rankine Cycle and the heating system is supplied by a solar collector network with a cost of 0.0477 USD/kWhele.