2. Energy simulation is a computer-based analytical
process that helps building owners and designers to
evaluate the energy performance of a building and
make it more energy efficient by making necessary
modifications in the design before the building is
constructed.
Based on algorithms - evolved and matured over time,
these tools simulate physical properties and behavior
of buildings; provide designers with an indication of
performance and help to make informed decisions.
3.
4. Certain energy simulation programs are designed to
work for individual building components such as wall,
roof, building form and fenestration.
Some tools are specifically used for modeling one or
more parameters such as lighting, heat transfer across
building envelope, natural ventilation, and shading
elements.
Whole building simulation tools are widely used and
are applied to the entire building as an integrated
system to capture the interactive effects of building
components and systems.
5. A simulation program takes into account
• The building geometry and orientation,
• Building materials being used,
• Building facade design and characteristics,
• Climatic parameters,
• Indoor environmental conditions,
• Occupant activities and schedules,
• HVAC and lighting systems and other parameters to analyze
and predict the energy performance of a building
6.
7.
8. NEED FOR ENERGY SIMULATION PROGRAMS
• Increased commercial building construction
• Expecting to create more comfortable indoor
environmental conditions.
• Increased pressure on supply side infrastructure
• Conventional computation methods are difficult.
• Usually “rule of thumb” by consultants and “expert
advice” of equipment suppliers played major role
in designing.
• For large complex commercial buildings it’s not
effective.
• Building regulations, energy labeling and tax
exemption for low energy buildings require energy
simulation.
9. HOW A SIMULATION PROGRAM WORKS
• A building’s energy requirements change continuously
• Simulation software is based on the process of modeling a real
phenomenon with a set of mathematical formulas. It is,
essentially, a program that allows the user to observe an
operation through simulation without actually performing that
operation.
• In theory, any phenomena that can be reduced to mathematical
data and equations can be simulated on a computer.
• The sequence of calculations is repeated many times to simulate
an annual operation cycle. The results of all the repeated
calculations are then compiled to produce the total yearly
energy consumption and costs.
• building is divided into “thermal zones.”
• A zone should have well-defined boundary conditions
10. All the sophisticated energy simulation programs
perform four basic groups of calculations. Different
programs link these calculations in various ways. It is
important to understand the general flow of
calculations as explained below.
• Space loads
• System loads
• Central Plant Loads
• Economic Calculations
11. ENERGY PERFORMANCE SIMULATION TOOLS ALLOW
DESIGNERS TO
• Consider the building as a single integrated system.
• Predict thermal behavior of buildings in relation to its outdoor
environment.
• Predict the impact of daylight and artificial light inside the
building.
• Model the impact of wind pattern and ventilation and assess
its effect on energy use.
• Estimate the size/capacity of equipment required for thermal
and visual comfort.
• Calculate the effect of various building components on each
other and predict resulting conditions and impact on energy
use.
• Assess the changes in energy consumption through sensitivity
analysis with respect to design changes affecting building
geometry and materials, components, systems, etc.
12. AVAILABLE COMPUTER ENERGY SIMULATION
PROGRAMS
1) WHOLE BUILDING SIMULATION PROGRAMS
• TRNSYS
• DesignBuilder
• OpenStudio
• ESP-r
• Green Building Studio® (GBS)
• Insight 360
• eQUEST®
• Energy Plus
• The IES Virtual Environment (IESVE)
15. IMPLEMENTATION OF COMPUTER
SIMULATION PROGRAM IN BUILDING
DESIGN
• SIMULATION SUPPORTED DESIGN PROCESS
(SSDP)
The structure of the SSDP was based on the
Royal Institute of British Architects (RIBA)
Design Plan of Work [RIBA 1995] which divides
the design process into twelve different stages
16.
17. Simulation can make a contribution to an
improved building design at three design stages
a) Outline Design Stage
b) Scheme Design Stage
c) Detailed Design Stage
18.
19. OUTLINE DESIGN STAGE
• simulation will be used to understand how
design decisions made in this design phase
might affect the performance of the building
• an indication of the expected building energy
consumption and in many cases also the
comfort conditions in the building.
• An analysis should also identify any
parameters that may cause problem(s) and
the scale and extent of the problem.
20. SCHEME DESIGN STAGE
• Most of the simulation exercises at this stage
will be carried out for typical sections of the
building or in areas where problems have
been identified.
• Simulation exercises carried out at the Scheme
Design Stage are more advanced than the
ones described above for the Outline Design
Stage and currently they are usually carried
out by a simulation specialist.
21. PARAMETERS INCLUDED IN THE DETAILED DESIGN
STAGE
• At the Detailed Design Stage, the building design
is worked thorough in detail.
• Any simulations undertaken will be for technical
reasons
• Examples of such simulation projects are:
• Assessment of passive cooling systems (e.g.
ground cooling)
• Assessment of passive heating systems (e.g. solar
preheat of air)
• Ventilation studies (design of natural ventilation
systems, displacement ventilation system)
• Test and refinement of heating and cooling
control strategies.
