Innovative co-simulation tool for assessment and optimisation of energy consumption in deep retrofitted buildings

The building sector has a strong impact in terms of energy consumption and greenhouse gasses emissions, for this reason the scientific community is dedicating an increasing attention to this sector. In this context, the REMOURBAN H2020 project has carried out a pilot deep refurbishing work on a small cluster of 10 homes. The interventions included the implementation of passive energy saving measures to the buildings envelope and the replacement of the old heating system, based on individual gas boilers, with an all new hybrid energy-supply system capable of satisfy both the space heating and the domestic hot water demand. This retrofitting scheme aims to achieve near-zero-energy homes level of performance at reasonable cost by offsetting part of the energy demand renewable energy produced in loco. The new layout is designed as a local low temperature district heating system and includes ground source heat pumps, photovoltaic panels, electric, and thermal energy storage devices. The management of the complex hybrid system requires a suitable control strategy to optimise the energy consumption and consequently running cost. With this purpose a co-simulation tool has been developed, coupling a model of the energy system built using Dymola/Modelica and the EnergyPlus model of the buildings. A subsequent expansion of the case study to a total of 27 dwellings highlighted the modularity of the co-simulation tool, as well as its ease of scalability. The co-simulation tool allows a precise assessment of the building energy performance before and after the refurbishment. It has also been used to develop different control strategies aiming to reduce the energy consumption from the grid, maximize the self-consumption of photovoltaic energy and ultimately move away from fossil fuel to sustainable energy resources