ESBO Manual
IDA Early Stage Building Optimization
About the manual
ESBO will often be accessed from a specific manufacturer or organization dealing with building indoor climate products. This ESBO provider will then supply documentation and tutorials to get you started. This user guide is independent of any single provider.
The guide addresses ESBO Light as well as the full (paid version of) ESBO. Therefore, some of the items discussed will not be found in the ESBO Light interface. Such passages are marked with a grey box like this:
Example of paragraph which only pertains to full ESBO.
In the next section, a general overview of usage is given. After this follows a more detailed description with several screen shots and detailed instructions about each input dialog, presented roughly in the order they appear in the tabs.
How do I use ESBO?
ESBO will always start with showing a Portal page, which is customized to each provider of the ESBO service. Here you will find links to tutorial material, support etc. The language that you want to use is also specified here. From the Portal page, there may be a number of ways of starting an actual case:
- By using a wizard, where you can select some very basic parameters to start off the further work or make simple simulations.
- Links to re-start an old case, which you have previously worked with.
- Links to other suitable start cases that have been proposed by the provider, such as typical office room, hospital room, residential building etc.
The present version of ESBO (v. 2.3) only has a single wizard, called Simple room. The details of the Simple room wizard are described in the next section. Here, we focus first on usage of the general interface, which opens after a wizard has been finished. (You will also get directly to this stage, if your start case has been saved after a wizard has been finished).
The general interface has three tabs: Rooms, Building and Simulation. The Room tab and the Building tab are where you define all the details of your building. Simulation experiments are carried out from the Simulation tab. The side bar to the left will show available components, different for each tab. The side bar can be opened and closed by clicking the 
symbol in the tool bar. To reopen the Portal page, press the 
symbol in the tool bar. The portal page can be left open while working with several models.
The first thing to do is to describe the typical rooms of the building. (Note: For ESBO Light, only a single rectangular room may be described.) This is done on the Room tab. Typical rooms are rooms that can be expected to have different indoor climate or service systems. If a building contains several identical rooms, only one of the rooms has to be modelled and that specific, typical room, can then be multiplied so that the total room area for that room type is correct. For example, if you have a building with 100 similar south facing offices, you only need to model a single one of these rooms. If you are only modelling a small building, you can describe all individual rooms of the building. However, for a large project, it is always better to model only a selection of rooms such as, for example, South facing single office room, North facing single office room, Open plan office, Conference room, Corridor space etc.
Windows and doors can be added to the room by dragging them from the left-hand palette directly to the surfaces in the 3D view. The exact size and position of the objects can be edited afterwards in separate dialogs. Windows and doors may only exist in external walls, i.e. walls facing outdoors. In fact, when you drag a window to a wall, that wall becomes external. Internal surfaces are light grey in the 3D view, while external have a brownish tone and they are generally thicker.
To redefine a surface from internal to external (or vice versa), you simply drag a construction of the right category to the surface. You can then double click on the surface to define the details of the construction.
Once the typical rooms have been described in terms of geometry on the Room tab, you enter the total floor area of each room type in the Rooms table at the bottom of the Room tab until the whole building floor space has been accounted for. Other significant total areas of the building are then automatically computed. By adapting the typical rooms slightly, e.g. by changing window areas or adding external wall area (use the Surface part object), you arrive at a model that matches the actual building in the key figures: total window area, total external wall, roof and ground area.
Once the typical rooms of the building have been defined, you describe internal heat gains for each typical room by selecting (and then possibly editing) usage patterns from a palette of common patterns. Similarly, the indoor climate standard for each typical room is selected.
At this stage, you switch to the Building tab.
In the Building tab, the first thing to do is to select the building location from the drop-down list. Select Download if you don’t find the appropriate location on the list. On the Internet site, you will find more than 3000 locations from all over the world.
Now, double click on the Ventilation system of the building. By default here, an air handling unit with a return air heat exchanger, a heating and a cooling coil has been defined. If you are happy with this setup, just select the heat exchanger efficiency and minimum discharge temperature (depending on defrosting), the pressure rise of the supply and return fans (or SFP). If you want a different type of system, drag it in from the palette. Note that air flows in the rooms have already been selected in the Room tab. The default central system will be able to supply any amount of tempered air. If you have selected exhaust only ventilation in the typical rooms (or unbalanced supply and return), the makeup air will come from increased infiltration.
Also in the Building tab, specify the domestic hot water consumption and the infiltration rate and then we are ready for a first simulation.
The rooms of the building are initially equipped with idealized room units for heating and cooling, called “Generic” units. These will heat and cool the rooms to maintain temperatures within requirements, but are not connected to the water based central system that is described on the Building tab. The Generic units provide heating and cooling to the rooms by directly converting some energy source (such as electricity, fuel or district heating). The systems that are described on the Building tab will supply hot or cold water needed by the air handling unit (AHU). When you start, a fixed efficiency boiler and similar chiller are present in the Building tab for this purpose.
If you don’t want mechanical cooling, remove the cooling systems from your typical rooms as well as the default chiller (that supplies the AHU cooling coil) from the Building tab. To remove the cooling coil from the air handling unit, just set its effectiveness to zero. It is nearly always best to make rough calculations with idealized systems first to compute needed sizes of other types of equipment.
To make a first set of simulations, switch to the Simulation tab. The first thing to do here is to simulate a severe winter day (Heating design). This will compute a heating need in all rooms that will later on be useful to select non-idealized room units and central systems.
Similarly, if you want to size a cooling system, run a summer day simulation (Cooling design). From version, 2.2 it is also possible to run an overheating study, and find the day with the highest temperature of each zone.
If you are in a truly early stage of the project and have not yet started to think about what particular supply systems to use for the building, go ahead with a whole-year energy simulation. This will enable you to optimize the building envelope first and then turn to a more sophisticated system description.
Once you are ready to start experimenting with different real system components, first go back to the Building tab. Here you specify the design temperatures of the air supply, the hot and, optionally, the cold water distribution systems. The next stop is the Room tab, where you replace the ideal room units with other options from the palette, such as radiators, fan coils or floor heating. In order to select a radiator or similar device, you must both have access to the heating demand of the room and of the system design temperatures. Note that the design power of most components, such as for example the radiator, are given with respect to a “rating condition”. If the actual temperature conditions differ from these, the emitted maximum power will not match the number that is given. Usually, the default rated conditions are standardized and will match those found in commercial technical data sheets. If you want the maximum power to match the given number, you can manually set the rated conditions to match the water and air temperatures of your simulation.