Energy Simulation

Occupants control indoor environments to meet their individual needs for comfort. The control of window is the most common natural ventilation method influencing indoor environment as well as the energy use of the buildings to maintain a suitable environment. Therefore a better understanding of window control behaviour of the occupants has significant implication to enhance occupant comfort with minimal energy consumption. The objective of this study was to identify an appropriate algorithm and variables to develop a predictive model for window control.

Recent studies examined a liquid desiccant indirect and direct evaporative cooling assisted 100% outdoor air system (LD-IDECOAS) as an energy conserving alternative to conventional air conditioning systems. An IDECOAS was introduced as an environmental-friendly air conditioning system that uses latent heat of water evaporation to cool the process air. Recently, studies suggested the integration of a liquid desiccant(LD) system with an IDECOAS to overcome a cooling reduction in evaporative cooling performance in a hot and humid climate.

Despite the software developments intended to facilitate the use of energy simulation programs by architects in the early design stage, a very limited guidance is available, leading to a limited uptake. This paper investigates ways to better inform architects about energy simulation, firstly by enabling them to identify and translate the design inquiries into simulation tasks for deriving productive decision support and secondly by familiarizing them with the concepts and processes involved in energy simulation.

This paper describes an effort to build and partially validate an energy model of an existing educational building located in Cambridge, MA, USA. This work was carried out as part of a research seminar for graduate architecture/design students and included four related tasks: Modelling the building’s geometry and thermal properties in DesignBuilder/EnergyPlus, generating a site-specific weather file based on near-site measured data, assessing internal load schedules based on a detailed building survey, and collecting monthly metered data for heating lighting and cooling over a whole year.

Time of use (TOU) electricity metering involves dividing the day, the month and the year in to slots or bands, with generally higher rates at the peak loads and low tariff rates at off-peak load periods. For this study, the statistically representative testcase Canadian house was modeled in the building energy simulation software ESP-r to estimate its sub-hourly (every fifteen minutes) electricity consumption for the appliances, lighting, domestic hot water (DHW) and space heating for an entire year.

The importance of analysing thermal performance in building design has grown, but it is still often done using simple static calculations or estimates. Accurate dynamic thermal simulation software have been available already for decades, but these tools are still not widely used by practitioners in building projects. The main barrier of wider usage of dynamic thermal analysis methods has been the required big manual input work. By utilising BIM as a data source for hermal analysis, the data input will be more efficient and the existing data more reusable.

This paper highlights the difficulty of using energy simulations to answer general questions in typical  building design scenarios. By analyzing the question, it is identified that problems of a search-based nature may encounter situations where an exhaustive search is impractical with reasonable resources. This paper presents the method of using heuristics to solve such questions within just a few simulations. While the solutions may not necessarily be guaranteed to be global or ideal, they are optimal within reasonable limits and sufficient for the types  of questions addressed.

Recently, in order to reduce energy consumption in the building sector, many air-conditioning systems have been proposed and applied to real buildings. Of particular note, air-conditioning systems that treat sensible and latent loads separately have been assessed as efficient in hot and humid climates. In this study, a highly efficient desiccant system combined with a cogeneration system and a heat pump desiccant system has been developed.

This paper describes the energy-saving effects of the proposed system with an active ventilation function and a heat pump for heat recovery. First, the temperature of the air supplied through the porous material versus the outdoor temperature was calculated using computational fluid dynamics to set the boundary conditions for the energy simulation. Then, the cooling/heating loads of a typical residential building in Japan were calculated and comparisons were made with and without the proposed system installed.

In Korea, in 2006, the building regulation was revised to apply 0.7 ACH (Air Change Rate) ventilation systems to improve indoor air quality in residential apartment housing. The purpose of this study is to evaluate energy requirement and indoor contaminant level characteristics for residential building applying with sensor-based DCV (Demand Control Ventilation) system.