The definition of energy plans that meet to different optimisation criteria, such as economic, technological and environmental ones, requires the use of scientific support tools that allow to quantitatively evaluate the impacts that each strategy can have on these aspects. The tools, depending on their degree of complexity, are called harmonised or integrated modelling systems. RSE’s previous experience has shown that one of the main limitations of the current energy-environmental evaluation systems is that often the energy model and the environmental impact assessment models operate independently of each other. This first of all means that the energy models only partially take into account the environmental implications of the different scenarios and do this in a simplified manner. Furthermore, the decoupling and the resulting inconsistencies between the databases used in the two modelling fields make it difficult and at times imprecise even the simple a posteriori assessment of environmental impacts. To overcome these limitations, this project proposes the development of a harmonised energy-environmental model aimed at efficiently and consistently assessing the environmental impact of energy policies, with particular reference to air quality. To this end, during the first year, a brief review of the modelling experiences already present at national level has been carried out, to be used as a reference for the subsequent development of the activities. A first methodological example of harmonisation between the energy model and the environmental model is also presented, in relation to the estimate of emissions from the road transport sector. A second essential aspect in the development of a harmonised/integrated system consists in the ability to examine in an extremely efficient way a wide range of solutions, or energy policies, quantifying their effects on the different objectives. In relation to the assessment of impacts on air quality, this requires the development of tools that efficiently reconstruct the relations between energy policy, emission scenario and atmospheric concentrations. To this end, a simplified emissions-concentrations model is defined and implemented, which summarises, through simple algebraic relations, the complex relationship between pollutant emissions and their corresponding atmospheric concentrations (metamodel). The model is applied, in a preliminary form, to the particularly complex context of the Po Valley, with an annual time horizon. The evaluation of the model’s performance, carried out through comparison with corresponding simulations of the complex model, concerned several air pollutants of interest in both regulatory terms (e.g., nitrogen dioxide and PM2.5) and modelling terms (e.g. nitrogen oxides and nitrate). For all the pollutants considered, the simplified model provided extremely positive results, assessed through appropriate performance indicators, in relation to the reconstruction of both the spatial variation and the temporal evolution of the pollutants. Therefore, the results obtained are an appropriate starting point both for the extension of the connection between the energy model and the emission model to the main anthropic sectors, and for the development of a simplified emissions-concentrations model to be applied on a national scale.