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The Site module contains the features needed for a Total Site™ project on a complete manufacturing complex. This type of project is complementary to a study of the individual units using the Process module. For example, the Process module considers direct heat exchange within a process unit. It can therefore be used to optimise each process in isolation. However, it cannot be used to consider opportunities for indirect heat or power integration between process units, via the site-wide utility system. In contrast, the Site module is specifically aimed at this higher level of analysis. In combination, therefore, Process and Site give a thorough analysis of heat integration benefits across the site.

Data is transferred into Site by automatically extracting it from Process files. This is done using a wizard which begins by asking you to select the Process files you are interested in and which types of data to retrieve. This can include stream data, utility data, existing heat exchanger matches and the Grand Composite Curve (GCC) at a user-specified ΔTmin. The wizard then asks the Process module to load each file and return the specified data. Finally, you see a report of the data that was retrieved.

Displaying and modifying data

Site provides extensive data management facilities.

	Reports of the stream data, utility data and utility heat exchangers for each process
	A report of the existing utility usage across the site
	A graph showing all the Grand Composite Curves on a single page
	A window that shows Grand Composite curves one at a time. Its main purpose is to allow the user to exclude or include pockets from the currently selected curve. The reduced curve will then be used in the subsequent analysis
	Status reports summarising the data that is available about the site
	A window to edit the utility stream definitions for the site. The initial definitions are created by merging all the utilities for all processes and removing duplicates

Note that all the data was imported in one step. This means that you can see all the data currently available for the site. You can then choose which types to use in the subsequent analysis. In addition, further data refinement takes place directly within Site. For example, by excluding pockets on the GCC.

Targeting methods

SuperTarget provides several different analysis options for Total Site.

The following targeting methods are available in Site:

	All process ideal
	In this method the analysis uses the grand composite curve for each process. This assumes that each process will be optimised for direct heat exchange between process streams.
	Existing P-U Network
	In this method the analysis uses the existing utility matches for each process. This assumes that none of the processes will be optimised for direct heat exchange between process streams. In this case we are deciding to "grey box" the processes i.e. not look at them in too much detail.
	Site Ideal
	In this method the analysis assumes direct integration across the whole site. This is the same as merging all the stream data together and targeting as if it were a single process. This gives an unrealistic result but can be useful to see an absolute lower bound.
	Process-specific
	If this option is selected then the user is free to choose different methods for different processes. For example, some of the processes could be set to "Existing P-U Network" whilst the remainder are set to "Process Ideal". With this option there is a further method available called "Stream Data". If this is selected then the stream data for the process will be used in the analysis. This allows you to create a dummy set of stream data to directly represent the desired process-utility interface.

Analysis results

The results of the analysis can be displayed using the following features:

	The source-sink profiles
	These display scope for generating steam at a certain level in one process and using it in another. They can be described as the composite curves of the site, drawn with no direct integration. The utilities are placed against these curves.
	The exergy source-sink profiles
	These are the same as the source-sink profiles but drawn in carnot factor co-ordinates. This allows you to visualise where exergy (i.e. power) is lost between the process streams and the utilities.
	The site utility report
	This summarises the utility loads across the site. It also reports the exergetic potential. This is the potential for producing power by generating the net steam consumption from the highest level and rejecting the net steam generation to the lowest level.
	The exergy site utility grand composite curve
	This allows you to visualise where exergy (i.e. power) is generated between the most extreme levels available on site and the net steam requirements at intermediate levels. There is also a version of this graph drawn in real temperature co-ordinates.
	The source-sink report
	This summarises the data that has been used in the source-sink calculations. This data is derived from the original process data, according to the analysis methods that were chosen. It also depends upon further refinements such as excluding pockets on the grand composite curves.