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The energy retrofit of existing buildings is a key strategy to reduce the energy costs of the building sector. Amongst the retrofit solutions, the adoption of mechanical ventilation systems represents a necessary approach for buildings with high crowding index, such as schools. The air quality in schools is a main issue since children spend a significant fraction of the year in such microenvironments. To date, the scientific literature has carried out several studies concerning the air quality in naturally ventilated schools worldwide, nonetheless most of the studies performed a general evaluation of the air quality just using the CO 2 as a comprehensive indicator. This is an oversimplified approach since the indoor air quality is affected by several pollutants, including airborne particles, whose behavior cannot be predicted by the CO 2 one. The aim of the research is the evaluation of the effect of the ventilation retrofit in a classroom on different indoor air quality parameters and energy consumption. To this end a mechanical ventilation system with a heat recovery unit was installed in a test-classroom and tests with CO 2 -based demand controlled ventilation were performed. CO 2 levels and indoor-to-outdoor particle concentrations were measured and compared to the pre-retrofit ventilation conditions (i.e. manual airing procedures). Results showed that mechanical ventilation systems have simultaneous positive effects on the different pollutants investigated as well as on ventilation heat losses: indeed, lower indoor-to-outdoor concentration ratios, with respect to the airing approach, were detected simultaneously for CO 2 , sub-micron particles and PM 10 .

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Abstract:Energy planning has become one of the most powerful tools for urban planning even if several constraints, (i.e., aesthetic, archaeological, landscape) and technological (low diffusion of Renewable Energy Sources, RES) reduce its spreading. An efficient and sustainable urban planning process should be based on detailed energy issues, such as: (i) the effective energetic characteristics and needs of the area like urban density and energy consumption, (ii) the integration of different RES and (iii) the diffusion of high efficiency technologies for energy production like cogeneration and district heating. The above-mentioned energetic issues and constraints must be constantly updated, in order to evaluate the consequences on environment and landscape due to new distributed generation technologies. Moreover, energy strategies and policies must be adapted to the actual evolution of the area. In this paper the authors present a Geographical Information Database System (GIS DB) based on: (i) the availability of land use (Land Capability Classification, LCC) to evaluate the productive potential; (ii) the estimation of residential energy consumptions (e.g., electricity), (iii) the integration of RES. The GIS DB model has been experimented in a wide area of Central Italy, considering exclusively the solar energy source for energy generation. OPEN ACCESSSustainability 2014, 6 5731

ISO 7726 Standard describes both the measurement techniques and the related metrological performances of instruments required for the assessment of the thermal environment.\ud Unfortunately the calculation of required discomfort and stress indices rarely takes into account the evaluation of single measurement uncertainties and their effect on the thermal\ud environment assessment. To assess the uncertainty in the determination of Predicted Mean Vote (PMV) and the Predicted Percentage of Dissatisfied (PPD) indices, required by ISO\ud 7730 for the verification of the environment conformity, typical uncertainties in the measurement of both physical (the air temperature, the mean radiant temperature, the air\ud velocity and the relative humidity) and subjective parameters are calculated. In order to verify the conformance of comfort indices measured by means of different measurement techniques\ud and devices, some experimental tests in three typical environments have been carried out: i) residential; ii) office; iii) industrial. To highlight both the compatibility of measurement and\ud the suitability the tests were carried out using three special comfort-analysis data-loggers each provided with different sensors characterised by different instrumental uncertainties

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