When modeling a district energy pipe network, it is vital to understand where the energy starts and where it goes. Modeling this real-world transportation of thermal energy through a pipe network, requires more than an understanding of how the pipes, pumps, heat exchangers, valves and other components are connected. To accurately represent these additional real-world complexities, we need a more advanced connectivity model. We need to leverage the Utility Network.

Last month, Esri released an updated version of the District Energy Data Model. The goal of the Esri District Energy Data Model is to make it easier, quicker, and more cost-effective for district heating, district cooling, and steam utilities to implement the ArcGIS platform. 

District Heating and District Cooling maps need to communicate vast amounts of information.   To help the District Heating and District Cooling community address this challenge, Esri has recently released a set of symbols created specifically for this industry.

Many of the processes a District Heating or District Cooling organization will target for improvement are associated around enabling organization staff to answer the question of “Where.” 

The first GIS based data model for District Heating and District Cooling has been released.

Looking for a better solution for managing your steam, heated water or chilled water pipe system? Please join us October 28^th from 11:00am – 11:30am U.S. Central time for a brief 20-minute presentation on using ArcGIS for managing the assets and systems of your District Heating, Steam, and District Cooling pipe systems. See all the details at: https://imgis2020.esri.com/exhibitors/11EAFD0B4900378082654F82FCF35551/See-a-Demonstration

This presentation is part of Esri’s Infrastructure Management and GIS conference. The conference is complementary to all Esri customers that are current on maintenance and subscriptions.

By Anastasiia Savchenko and Tom DeWitte

The summer is done, and the falling leaves are hinting that winter is coming. But progress on the District Heating and Cooling (DHC) data model continues its steady pace to completion.

Since the late August release of beta 1, we have been working towards a mid-October release of beta 2. This will be the final beta before the release of version 1 later this year. With beta 2 the data model is feature complete, and many of the lessons learned from testing have been incorporated. Overall, this effort is on track to be completed before 2020 ends.

Here is a brief summary of what’s left to be accomplished prior to the release of version 1.

Data Model

During the month of September testing was performed to check the ability to create and maintain information managed with the data model.  More challenging was the testing to verify that the structure network defined for this data model could be loaded into existing Esri Utility Network data models for water, electric, and gas.  Issues identified by these rounds of testing have been incorporated into the beta 2 version of the data model.  Beta 2 is feature complete. No more modifications other than corrections identified thru testing are planned before the final release.

Data Dictionary

Writing a data dictionary is not fun, but it is very important to explain the what, the how, and the why of the data model.  Work on the data dictionary has been ongoing and is currently about 66% complete. This data dictionary will include a description of each feature class subtype layer.  For each subtype layer, a full description of each attribute that is appropriate is provided. Additionally, the data dictionary will include a listing and description of each attribute rule that is to be included with the data model.

Sample Data

The sample dataset continues to evolve.  More detail has been added as well as continual cleanup of the pipe system connectivity.

Symbols

As this data model nears completion there is one more outstanding task.  This is the task to create an iconography-based symbology style set specifically for this data model. Being an iconography-based symbol means, no alphanumeric characters. The goal is to use universally recognized images to represent each unique type of asset.  These types of symbols can be used world-wide regardless of the native language. 

Test Drive

If you are interested in reviewing and testing this data model, you can download the ArcGIS Pro 2.6 compatible asset package from here: https://community.esri.com/docs/DOC-15522-district-heating-and-cooling-data-model-beta-2 

If you are interested in deploying this data model to support your system or record needs, please let us know.  You can contact us via geonet or directly via email: tdewitte@esri.com, asavchenko@esri.com .

By Anastasiia Savchenko and Tom DeWitte

The Esri User Conference is done, and summer is rapidly coming to an end. But progress on the District Heating and Cooling (DHC) data model continues.

Since the early July release of Alpha 4, we have been working towards a mid-August release of beta 1. The goal for beta 1 is to have a complete rule base, network attributes, summary attributes, attribute rules and subnetwork definitions. With these additions to the data model we are getting very close to being feature complete. Let's discuss these remaining items in detail.

Rules, Rules, Rules

         A key component to the Utility Network is its ability to help data editors to enter and update components of the pipe system correctly. This not only improves data quality it also improves editing efficiency by helping editors enter the information correctly the first time.  The upcoming beta release will be the first release with a full set of connectivity rules to join the previously defined sets of containment and attribute rules.

Network Attributes

Network attributes are the utility network variables that allow summary attributes and trace tasks to be able to leverage a feature’s attributes.  This upcoming release will contain an updated set of network attributes.

Summary Attributes

  For each unique type of subnetwork, a specific set of summary attributes can be defined. These summary attributes will leverage a network attribute to define the information from the pipe system components to be summarized for a specific subnetwork.  For example, each pressure zone currently has the following summary attributes which the software will automatically tabulate.

• Total Pipe Length
• Total Transmission Pipe Length
• Total Distribution Pipe Length
• Total Supply Pipe Length
• Total Return Pipe Length
• Pipe Volume
• Number of Valves
• Number of Pumps
• Number of Heat Exchangers
• Number of Expansion Joints

Testing and more Testing

Before the beta can be released, there needs to be testing of the rule base and testing of integration with the other domain specific data models.  This is an important step to insure that multi-utility organizations are able to easily append this DHC 2020 data model onto electric, gas ,water, and other Esri domain specific data models.

Almost Done

            There are still a few aspects to modeling District Heating and Cooling systems that need to be completed.  First is understanding how to correctly model a Leak Detection system so it can be created, maintained, and traced with minimal effort and no duplication of data.  Second is the creation of a data dictionary, and third is the creation of a symbology style set.

Conclusion

            Even though there are still a few outstanding items to complete, this effort is on schedule.  But we are always looking for more volunteers with industry knowledge to help with this effort.  If you work in, or support the Steam, Heated Water, or Chilled Water utility organizations and are interested in joining one of our working groups, please let us know.  You can contact us via geonet or directly via email: tdewitte@esri.com, asavchenko@esri.com .

By Anastasiia Savchenko and Tom DeWitte

In May, we published the first progress update about a new Esri initiative to create District Heating and Cooling Data model. This post is the continuation of the effort to keep you informed about the District Energy data model's latest developments.

The newest release of the data model is Alpha 4, and it includes the updated sample data, attribute rules, terminals, subnetworks, and heat exchanger configurations. Let's discuss all these changes in more detail.

DOWNLOAD THE ALPHA 4 PACKAGE  

Sample Data Progress

It is vital to provide a sample dataset, a well-thought digital twin of the several district energy system configurations. Thus, the sample data's newest version includes the supplemental configuration of the hot water and chilled water systems. Modeling this way is suitable when the district energy system serves several buildings (for example, row houses), but it measured by one meter. In this scenario, the meter measures consumption at the end of the service line, from which energy transported to multiple buildings through the network of customer pipes. Often urban areas with high population density have limited underground space, making it essential to use such system configurations.

Introduction of the Business Rules

Improving the editor's experience through automation and a strong rule base to help the editor enter the information correctly the first time is a key benefit of business rules.

Alpha 4 is the beginning of the inclusion of attribute rules to the data model template. Attribute rules are a principal geodatabase capability of the Utility Network technology. Adding these rules is essential. They will make sure that your digital twin satisfies the business-specific requirements of the industry.

The Alpha 4 release of the DHC data model includes a set of calculation attribute rules. Calculation attribute rules are responsible for an automatic population of the attribute based on the defined expression. An excellent example of this is the rules which will calculate pipe surface area and pipe volume based on the pipe shape length and diameter.

More attribute rule calculations and attribute rule constraints will be added in the beta release of the data model template.

Introduction of the Contingent Values

In addition to the attribute rules, the Alpha 4 DHC data model includes contingent values. Contingent values are the recently-added capability of the geodatabase. Their primary function is to prevent users from entering invalid values by restricting the list of valid values for the attribute field.

For example, the pipe selection of the materials available to the user changes based on the type of the system the pipe belongs to – whether it is hot water, steam, condensate, or chilled water system.

Terminal Configurations

In Utility Network, it is possible to model devices with a higher degree of realism by defining terminals. In the district energy system, terminals represent the incoming and outgoing flow of the hot water, chilled water, steam, or condensate.

The newest DHC Alpha 4 data model includes terminal configurations for the bypasses, customer connections, and heat exchangers. The newly added terminal configuration of heat exchangers is critical to tracing analytics with this data model template. It allows for downstream traces that follow thermal energy flow through the heat exchanger and follow water flow, circulating into the heat exchanger, and then loop back.

Subnetwork Configurations

Besides attribute rules and terminals, the Alpha 4 DHC data model continues to build the subnetwork configurations. Subnetworks model the subsystems of a District Energy pipe system such as thermal energy system zones, pressure zones, and circulation zones. Subnetwork consists of all the participating features in the topological subset of the tier. These features include devices, lines, and junctions.

Modeling of thermal energy flow vs. water flow

In the district energy system, the commodity: hot water, chilled water, or steam; being transported thru the pipe system is not consumed directly by the end consumer. Instead, commodity transports and delivers the thermal energy it carries. In comparison, in other utility systems, the commodity consumed at the customer location. For example, drinking water runs from the tap; electricity provides light and power to the appliances; gas feeds the stoves and heating units. In these typical examples, the commodity runs from the source to the consumer device where it is consumed (sinks).

The customer does not consume the district energy commodity. Instead, commodity warms or cools the surroundings through which it runs due to a combination of thermal processes - convection, conduction, and radiation. The heat exchanger is the device used to transfer the thermal energy without also continuing the flow of the commodity, which creates a unique modeling situation for district energy systems.  The flow of thermal energy is not always the same as the flow of the water or steam!

The Alpha 4 release is the first release to provide a configuration that allows users to perform traces of the water flow through the pipe system and trace the thermal energy flow through the pipe system.  Here are some videos to show you downstream traces of the thermal energy and the water flow.

You can run the trace for water flow through circulating with the heat exchanger (scenario 1).

Or you can run the trace of the thermal flow through the heat exchanger (scenario 2).

Not Done Yet

There is still lots to be done! Although it is summer and work is usually slow due to vacation, the goal of the community is to stay productive and continue evolving this data model template.

As the model moves from alpha to beta, you will see further refinement of the subnetwork definitions, summary attributes, and network attributes.  You will also see the addition of more attribute rules and connectivity rules.  Stay tuned!

Conclusion

Even though there is much yet to do, this effort is on schedule.  But we are always looking for more volunteers with industry knowledge to help with this effort.  If you work in or support the Steam, Heated Water, or Chilled Water utility organizations and are interested in joining one of our working groups, please let us know.  You can contact us via geonet or directly via email: tdewitte@esri.com, asavchenko@esri.com.

By Tom DeWitte

In January 2020, Esri launched an initiative to create a Utility Network data model that would enable District Heating and Cooling industry (DHC) customers to more fully leverage the ArcGIS platform. From the beginning, this was undertaken as a collaborative effort involving Distributors, Business Partners, and customers. To assure the initiative factored in regional requirements, working groups for North America, Europe and Asia were formed.  These working groups are comprised of volunteers from DHC organizations, and the business partners and Esri Distributors who support them. These working groups started meeting virtually twice a month in March.  This blog is an update on the progress made by these working groups in our efforts to create a geodatabase data model for Steam, Heated Water, and Chilled Water pipe systems with the Utility Network capabilities, by the end of 2020.

Its Taking Shape

In February of 2020, a team of Esri staff started meeting with DHC organizations to begin the process of understanding these pipe systems and the assets which comprise them. Thru March and April the aggregated feedback from these organizations has started to coalesce.  With this coalescing of feedback, a geodatabase data model with utility network capability is starting to take shape.

As the feature class subtypes, attributes, coded domains, and default values settle into a final schema, other aspects of a geodatabase data model are starting to be defined.  These are the business rules of District Heating and Cooling.  In the just released Alpha 3 version of the data model, you will see some initial defining of Contingent values.  Over the course of the summer, this will be expanded to include attribute rule calculations and attribute rule constraints.

Alpha3 will also be the first iteration of the data model to start to include the Utility Network specific definitions and rulebase. With Alpha 3 you will see the first iteration of definitions for the pipe system tier group, and its tiers of system and pressure. Alpha 3 will also include beginning rulebase definitions for containment and connectivity.  These too will be enhanced thru additional iterations over the course of the summer.

We Have Sample Data

We have data!! 

A sample data set is an important part of the data model template download.  It allows everyone to see through a map what part the data model assets play in the pipe system and where in the pipe system these assets appear.

With the alpha 3 posting of the DHC 2020 data model, we will be including for the first time our developing sample data set.  This data set will include examples of steam, heated water, and chilled water pipe systems.  You can download the DHC 2020 Alpha 3 version here.

Much Yet To Do

Building a spatially aware data model requires a little more work than defining a standard relational database data model.  Over the next several months, the working groups will continue to build out this data model.  This work will center around how the inventory of DHC pipe system assets interact with each other.  With upcoming releases of the data model over the summer of 2020 you will see the result of this effort in the defining of:

                - Connectivity rules to define how this pipe system should be assembled

                - Containment rules to define within which facilities these assets are allowed to reside

                - Contingent values to define the dependency between an asset’s attributes

                - Attribute rules to automate data entry and improve data quality

                - Subnetwork definitions to define the subsystems of the pipe system    

There is much yet to do.

Conclusion

Even though there is much yet to do, this effort is on schedule.  But we are always looking for more volunteers with industry knowledge to help with this effort.  If you work in, or support the Steam, Heated Water, or Chilled Water utility organizations and are interested in joining one of our working groups, please let us know.  You can contact me via geonet or directly via email: tdewitte@esri.com.