Hi,
I am working on a LEED project. The generation
systems exist for conditioning the building. These are trigeneration (CHP) systems
each with a capacity of 2020 kW that are used through the year. In heating
seasons, the building is conditioned using the jacket water of these systems.
In cooling seasons, the exhaust gas thermal energy is utilized using absorption
chillers. These systems produce electricity through the year in order to
support building electricity demand. By the way, there is another plant group
includes boilers, chillers and cooling towers as backup HVAC systems that are
used during periods of increased heating and cooling demands.
For modelling of these systems, I utilize the â??Treatment
of District or Campus Thermal Energy in LEED V2 and LEED 2009 ? Dessign &
Constructionâ?? guide. However, I am confused about some requirements in this
guide. I selected â??Option 2â?? for modelling these systems. In Option 2, a
virtual plant with average capacities is constructed for proposed building if necessary
plant data is not available. However, I
have data of all backup systems and their efficiencies are higher than default
efficiencies of virtual plant. Therefore, I modelled these backup systems instead
of a virtual plant. Besides, I can compute the electric output and fuel input
of CHP systems according to Appendix D in a guide. Finally, I can ensure all
requirements until the end of Appendix D.
However, I am really confused about â??Heating
converted to cooling as part of the LEED Projectâ?? section in Appendix E. In project,
absorption chillers utilize from exhaust gas thermal energy of CHP system and convert
this energy to chilled water for cooling a building as described in this
section. Therefore, I need to model district heating source and absorption
chiller for baseline building according to requirements described in first and second
step of this section. I am really confused about these steps about how can I
model district heating source. If I select Option 1, I need to model purchased
heating. It is very clear. However, it is mentioned about â??code-compliantâ?? as described
below:
For
Option 2 ? Aggregate Building/DES Scenario: use a virtual upstream DES plant
for the Proposed Case and compare it to code-compliant on-site equipment for
the Baseline Case as described above in Section 2.4.
Could you please give me an idea about what is â??code-compliantâ??
and how can I model district heating source of Baseline Building according to
these sections?
By the way, it is mentioned about modelling
absorption chiller for proposed building based on the as-design type in fourth step.
I think it is more complicated than first step and second step. Why I need to
model an absorption chiller for proposed building? How can I ensure heating
source of this absorption chiller? In project, heating source of absorption
chiller is CHP system and it is mentioned about modelling absorption chillers based
on the as-design type. Therefore, do I need to model CHP system for creating
heating source? If so, it is not sensible because I select Option 1 if I would
like to model CHP system.
Could you help me about my problems described above?
Kind regards
Alpay Akguc