The Role of Energy Management Systems in nZEB and nZEC

In the near future, buildings will have to meet strict energy consumption standards in order to get as close as possible to the concept of nZEB (nearly Zero Energy Building), which means that buildings need to produce to a very large extent (10% for Romania) of their energy demand using renewable systems (RES) mounted on or near them. These standards can be met by at least three paths, simultaneously implemented: (a) reducing buildings losses, (b) designing renewable energy systems (RES) according to the constructive and architectural restrictions of the implementation location and (c) optimally managing the energy consumed by the building so that all available renewable sources are used at their maximum potential and only a minimum amount is consumed from conventional sources (fossil fuels). Implementing all described RES at building level (in order to meet nZEB standards) can raise real problems due to space or renewable source limitations. On the other hand, at district or even at city level the solutions for implementing all types of RES are more diverse and may support the local inhabitants to directly benefit from the advantages of nearly Zero Energy Communities (nZEC), if appropriate energy management systems (EMS) are used. The paper describes the basic principles of EMS focusing mainly on electrical energy, presents the renewable energy systems available in a newly established research community and proposes a management algorithm able to efficiently use the produced electrical energy considering local restrictions.