English

The district heating system should be accepted as a technical system, functionally and workable to provide heat for thermo technical needs of a higher number of different and connected us ers being located on a wider area usually in urban environment. The thermo technical needs of users mean the needs for heating, ventilation, air conditioning, and preparation of consume sanitary hot water and/or for special purposes. The district heating system on defined quality level provides heating and its delivery to users.

New distributed simulation environment has been used to simulate the energy flows in a simple case community consisting of four buildings, power plant and a district heating network. Distributing computing task on different computers accelerates the simulation, but simultaneously some time is spent on communication. The tests indicated that a one year energy simulation of a community could be performed within 3.5-10 days of calendar time depending on the time step used. It was also found that the Internet-communication of data takes approximately 20-25 % of the total simulation time.

In this paper, we present the economic analysis of a solid-oxide fuel-cell (SOFC) micro-cogeneration plant in a single-family low-energy house in Finland. Here, we implement a new solid-oxide fuel-cell (SOFC) model in the dynamic building simulation software IDA Indoor Climate and Energy to obtain a match between energy demand and supply.

We investigate optimal supervisory control of a building energy system with cogeneration of heat and power (CHP). The system consists of a Stirling engine and a supplementary burner, space heating and a domestic hot water (DHW) storage tank. Cost and primary energy (PE)-optimal operation are considered.
The best theoretically possible operating strategy is found using the following assumptions:

The ICEO Project quantifies the thermal and electrical energy consumption in hospitals of an Italian region (Lazio Region). 26 out of the 57 (45,6%) hospitals of the region were selected for a questionnaire in order to acquire information about activities, structural characteristics, technologies and the energetic consumption during the years 2001-2003. Only 61,5% of the selected hospitals supplied the required information. The consumption data show a great variability between hospitals, not always explained by their technological level or by their complexity.

The energy consumption and indoor temperature of 9 housing units sited in the northern region of Honshu Island, Japan were investigated for a full two years from Dec. 2002 to Nov. 2004. Three of the houses were installed with all-electric equipment. The annual and daily energy consumption profiles of two typical houses were analyzed, and the annual energy consumption per house was found to range from 40GJ/year to 120GJ/year. In some houses, energy consumption during the second year decreased due to a rise in energy saving awareness.

In this paper insight is given in the potentials for energy efficiency and renewable energy sources, specifically when applied to the built environment in the Netherlands. To this end, an analysis is presented of the building stock development from now to 2050 and building concepts and scenarios for a mid-century energy-neutral built environment in the Netherlands. Special attention is given to the potential of energy management systems in buildings.

A global methodology is developed to optimize concepts for extremely low energy dwellings, taking into account energy savings, environmental impact and financial costs over the life cycle of the buildings. Energy simulations are executed with TRNSYS. The ecological impact is evaluated through a life cycle inventory of the whole building, whereas costs are evaluated through a cost-benefit analysis. The multi-objective optimization problem is solved with a combination of genetic algorithms and the Pareto-concept. Firstly the optimization methodology is presented.

The performance of “hybrid controlled” trickle ventilators, that is background ventilators whose opening area depends upon both the pressure difference across the vent and the relative humidity of the room air, are investigated by means of computer simula

Many naturally ventilated building designs rely on buoyancy (or “stack effect”) and night cooling of the structure. It is well known that for an exposed building, even mild winds can produce pressures well above those due to stack effect. It is also commo