## 2 Materials and Methods
In the European area, the S2S4E Decision Support Tool (DST) has been developed as an operational climate service for clean energy. The DST generates climate information adapted through energy indicators derived from climatic variables such as wind speed, solar radiation, precipitation, temperature and pressure reduced to the average sea level. These indicators provide information on the expected variability in hydroelectric, solar and wind energy production, as well as on electricity demand in the future. Last, but not least, one of the oldest and largest adopted tools for clean energy management is RETScreen, developed by the Canadian Government with NASA cooperation. In 1996, RETScreen clean energy management software was developed by Natural Resources Canada; after that, in 1998 the software package was carried on by the Canadian government. The tool can be used for numerical analysis in areas such as energy generation and efficiency, prices, emission reductions, financial viability and hazards of various types of clean energy and energy-efficient technologies. This simplifies initial assessments and provides streamlined processes that enable funders, architects, designers, regulators, etc. to make decisions on future clean energy initiatives. This software is able to exploit post-processed satellite data and guides you through a very simple path from system project to cost analysis, in order to understand if, for example, some smart building or energy plant realization is feasible or not. It includes modelling for many renewable energy systems and the expected costs for the plant characteristics so you will be able to have an approximate, but flexible, estimate on the project you are working on. The tool has already been used for projecting many installations all over the world: (i) to validate the techno-economic and environmental sustainability of solar PV technology in Nigeria [28], (ii) to evaluate and compare economic policies to increase energy generation capacity in the Iranian household consumption sector [29], (iii) to provide a technical, financial, economic and environmental pre-feasibility study of geothermal power plants in Ecuador [30] and (iv) to provide a preliminary determination of the optimal size for renewable energy resources in buildings [31]. RETScreen Expert software in its latest available version (7.0) has been adopted to provide useful case studies of projects involving renewable energies in contrast with standard power production. The open-source version (only viewer mode) has limited features, but it is still reliable for feasibility analysis of many projects, starting from smart buildings to power plants [32]. The first case study to be proposed is a multiple technologies power plant, combining geothermal and hydric power [33], as shown in Figure 2. In particular, water and geothermal power have been exploited in different percentages, so that the combination can provide 35,033 MWh as electricity export to the grid, reducing CO2 emissions by 15,676 tCO2 (equivalent tons of CO2). Figure 2: Schematic of the integrated biphase back-pressure system [26]. The type of power plant and the location are the first step choices to go through. For this case study, the installation place is in Mexico. Mexico's renewable energy contributes 26% of Mexico's electricity generation. The majority of renewable energy adoption comes from hydro, geothermal, solar and wind power. Long-term efforts are being made to increase the use of renewable sources of energy. The sum of geothermal energy used and extracted ranks Mexico as number four in the world. Starting from a template of RETScreen software, latitude, longitude and altitude of both selected location (Mexicali) and the facility to be set is provided. The climate zone is individuated automatically to be that of Ensenada (the closest place to the facility being mapped for climate reference). Mexicali is the capital of the Mexican state of Baja California. It covers an area of more than 13,000 km\({}^{2}\) and it counts more than 900,000 inhabitants.