Due to desirable emission reductions and population growth, an increasing energy demand isidentified as a dire issue for energy systems. The introduction of low energy building districtsenables an increased energy system efficiency. This study’s aim is twofold. Firstly, an extensive urban building energy model is used to simulatethe yearly use and geographic distribution of the heat demand for residential and commercialbuildings that are to be supplied by a low-temperature district heating system. Two buildingenergy performance cases are studied; one where all buildings are assumed to be of PassiveHouse standard, and one where the building energy performance is in line with conventionalnew-building regulations in Sweden. The study showed that that Passive Houses will generatethe lowest yearly heat demand and that implementation of ventilation heat recovery has a bigimpact. Furthermore, the results showed that a variation of building energy performance mightbe advantageous when planning a new city district with district heating. Secondly, one specific building is in detail modeled as Passive House and according to BBR-standards and simulated in the building energy simulation software IDA ICE to investigate whatbuilding heating system is best suited for low-temperature heat supply. The temperaturedemands for floor heating and low tempered radiators is investigated and compared toconventional water-based radiators. Results showed that floor heating requires lowertemperature’s than low temperature radiators, but both are well suited for low temperaturedistrict heating. The study’s results will be used as an example for future city district planning aswell as presenting relevant heating systems for low-temperature district heating.

Les exigences croissantes sur l'efficacité énergétique des bâtiments, l'évolution du {marché} énergétique, le développement technique récent ainsi que les particularités du poste de chauffage ont fait du MPC le meilleur candidat pour la régulation thermique des bâtiments à occupation intermittente. Cette thèse présente une méthodologie basée sur la commande prédictive distribuée visant un compromis entre l'optimalité, la simplicité et la flexibilité de l'implantation de la solution proposée. Le développement de l'approche est progressif : à partir du cas d'une seule zone, la démarche est ensuite étendue au cas multizone et / ou multisource, avec la prise en compte des couplages thermiques entre les zones adjacentes. Après une formulation quadratique du critère MPC pour mieux satisfaire les objectifs économiques du contrôle, la formulation linéaire est retenue. Pour répartir la charge de calcul, des méthodes de décomposition linéaire (comme Dantzig-Wolfe et Benders) sont employées. L'efficacité des algorithmes distribués proposés est illustrée par diverses simulations. / The increasing requirements on energy efficiency of buildings, the evolution of the energy market, the technical developments and the characteristics of the heating systems made of MPC the best candidate for thermal control of intermittently occupied buildings. This thesis presents a methodology based on distributed model predictive control, aiming a compromise between optimality, on the one hand, and simplicity and flexibility of the implementation of the proposed solution, on the other hand. The development of the approach is gradually. The mono-zone case is initially considered, then the basic ideas of the solution are extended to the multi-zone and / or multi-source case, including the thermal coupling between adjacent zones. Firstly we consider the quadratic formulation of the MPC cost function, then we pass towards a linear criterion, in order to better satisfy the economic control objectives. Thus, linear decomposition methods (such as Dantzig-Wolfe and Benders) represent the mathematical tools used to distribute the computational charge among the local controllers. The efficiency of the distributed algorithms is illustrated by simulations.