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The thermo-hygrometric treatment related to the air change in buildings requires a relevant quota of the total energy demand of HVAC systems, especially when the ventilation demand is significant. A correct energy saving strategy therefore should always focus on the use of suitable techniques to reduce this energy consumption. As proved by the modern theories on comfort, less strict values can be accepted for the internal humidity set points without compromising indoor comfort conditions. In addition, Demand Controlled Ventilation (DCV) gives the opportunity to reduce energy requirements. This paper investigates the opportunities offered by the installation of a DCV system and a Building Management System (BMS) able to perform long term monitoring of the HVAC system in a real case study. This refers to a historic building in Venice in the area of the harbour and recently transformed into a modern university facility. Starting from the experimental data recorded by BMS, an optimization of the control strategies and simple tuning actions of the DCV controller were possible. Results validate the use of more flexible set points of indoor relative humidity and long term on-line tuning even in absence of self-learning control systems, as well as they highlight the achievement of remarkable energy savings thanks to these actions. The research demonstrates the fundamental contribution of successive control performance assessments by long term monitoring to individuate possible weaknesses in DCV system management.

Among the policies and regulations aimed at reducing the energy use in building stocks, the retrofit of historic buildings is one of the hardest challenges both for research and practice, because it is necessary to combine the traditional energy/economy targets with safeguard programs and conservation theories. In this paper, a decision support system is developed in order to plan and manage energy retrofit campaigns tailored for cultural heritage. Costs and energy uses are assessed, as well as the compatibility of interventions and their impact on indoor environmental quality. The energy use is seen under an economic, environmental, human and cultural perspective, providing a decision-making procedure that could be very useful for asset holders, public or private investors as well as for portfolio managers or agencies. The most important achievements in this work are the assessment of a so-called restoration score as a way to include conservation aspects in the selection procedure, and the integration of different appraisal techniques such as multi-attribute analysis, life cycle costing and analytic hierarchy process.

The increased generation of electricity from renewable energy sources may imply issues in the management of national electric systems, due to the low predictability of electricity generation from renewable energy sources. In this regard, interesting opportunities come from the use of advanced control strategies for the management of electric devices such as heat pumps, able to exploit dynamic electricity prices aimed to induce users to absorb/generate electricity according with the electricity grid imbalance. In this paper, the results of building energy simulations applying tailored heat pump control strategies suitable for the integration within smart grids are presented. In particular, three heat pump control strategies are applied, whose action is based on the cost of electricity (absolute and relative to the following 12 h) and on the level of the local electricity generation from photovoltaics. The analyzed control strategies ensure relevant money savings (up to 30%) and increase the degree of energy self-consumption (up to 12% for exported electricity and 22% for imported electricity). The analysis considers also comfort issues and shows that the best results may be achieved commanding the heat pump basing on the generation of the photovoltaic system as well as on the simultaneous heating/cooling loads and electricity prices.