Development: possibility of defining electric storages

Hi @chris @MingboPeng

I hope you are pretty well.

I am reaching out to discuss the potential development of a dedicated electric storage component (e.g., for battery systems) within the Ladybug Tools ecosystem, additionally for use with Dragonfly and URBANopt. Such a component would significantly enhance the ability to model and harness energy flexibility at both building and community scales, especially in the context of renewable energy integration and urban energy planning.

To support energy flexibility and align with the capabilities of EnergyPlus (which underpins much of URBANopt’s energy modeling), I suggest the following features for the electric storage component:

  1. Battery Storage Model:
  • Support for both simple and kinetic battery models (similar to EnergyPlus’s ElectricLoadCenter:Storage:Simple and ElectricLoadCenter:Storage:Battery objects).
  • Parameters for:
    • Nominal capacity (kWh).
    • Maximum charge/discharge rates (kW).
    • Round-trip efficiency (%).
    • State of charge (SOC) constraints (minimum and maximum SOC).
    • Thermal losses impacting zone heat gains (if located in a conditioned space).
  • Option to specify battery type (e.g., lithium-ion, lead-acid) for more detailed kinetic modeling.
  1. Flexible Scheduling:
  • Input for charge/discharge schedules to control when the battery stores or releases energy. For example:
    • Charge during off-peak hours or when renewable generation exceeds demand.
    • Discharge during peak electricity price periods or high-demand hours.
  • Support for schedule inputs compatible with Ladybug Tools’ data collections (e.g., hourly or sub-hourly schedules).
  1. Power Input and Output Control:
  • Ability to define specific power inputs (e.g., from PV arrays, wind turbines, or backup generators like diesel engines (wind turbines and diesels are not still developed in LB, what it is possible for this maybe something like spreadsheet input at the moment)).
  • Support for scenarios where power generation exceeds demand (e.g., diesel generators producing surplus power during outages), allowing excess energy to be stored rather than wasted.
  • Integration with Electric Load Center logic (inspired by EnergyPlus) to manage power flows between generators, storage, and building/community loads.
  1. Community-Scale Integration:
  • Compatibility with Dragonfly for modeling district-scale energy systems, enabling batteries to be shared across multiple buildings or centralized at the community level.
  • Integration with URBANopt to optimize storage operation within district energy systems, considering:
    • Aggregated load profiles across buildings.
    • Time-of-use (TOU) electricity tariffs and demand charges.
    • Renewable energy forecasting and grid interaction (e.g., net metering, grid export limits).
  • Support for modeling microgrids or virtual power plants, where storage plays a key role in balancing supply and demand.
  1. Interoperability with Other Systems:
  • Ability to connect storage to renewable energy components (e.g., PV arrays modeled in Ladybug) and backup generators (e.g., diesel or natural gas engines).
  • Support for AC/DC power flows, including inverter efficiencies (e.g., using EnergyPlus’s ElectricLoadCenter:Inverter and ElectricLoadCenter:Storage:Converter objects as a reference).
  • Option to model storage as part of a hybrid energy system, combining renewables, storage, and grid power.

I found the attached OSM examples, maybe helpful. The main drawbacks of this kind of equipment in the OpenStudio is the lack of visual representation of the equipment, such as batteries.
pv_and_storage_facilityexcess.osm (322.7 KB)
storage_liion_battery.osm (79.1 KB)

Thank you very much for your support and assistance.

Sincerely
Behnam
NUI Maynooth, Ireland

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Hi @behnammmohseni thanks for your detailed feature request and sample osm files. I will review it this weekend and keep you posted.

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An update, I have not forgotten about this. I have checked your sample files and E+/OpenStudio documents, it is possible to support ElectricLoadCenter and its sub-objects in Ironbug. I will keep you updated.

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Hi @MingboPeng
I hope you are pretty well
Fantastic, thanks very much for your update. Looking forward to hearing from you.
Thanks very much for your time and assistance

Hi @MingboPeng @chris

I hope you are pretty well

Sorry I forgot one important thing, to have that kind of selling/buying for the energy flexibility scenarios with on-site generation, ElectricLoadCenter:Transformer‎ should be in the simulation (Fig 1.206 from EnergyPlus InputOutputReference):

Below is an example of OSM for the transformer:

transformer.osm (318.4 KB)

The OSM model I previously attached ( pv_and_storage_facilityexcess.osm) has the process of selling to the grid but without integration of transformer, most probably EnergyPlus uses some kind of simple equation or empirical for the power flow, …

But in real case, it should be ElectricLoadCenter:Transformer‎ to perfectly manage the task.

As an example those excess with PV that EnergyPlus has are in a single phase, which if you want to go for three phases, it cannot handle and you need the transformer.

@MingboPeng I would appreciate it if you could kindly develop thess transformers in IronBug.

I have found one good example in the EnergyPlus GitHub repo, it is in IDF and it has several things like: Diesel Generators, Gas Turbine Generators, Microturbine Generators with Transformer in 3 Phase. I run the IDF in LadyBug and it works and simulates without a problem. The challenge here is that LadyBug does not produce the OSM file using the HB Run IDF, so I use OpenStudio Application to import the IDF, run and save the OSM file (@chris another development here could be to enable OSM output for the HB Run IDF). Please find the attached IDF and the OSM for this Generators_Transformer.

Generators_Transformer.idf (122.8 KB)
Generators_Transformer_OSM.osm (108.4 KB)

The above simulations does not have batteries but the below OSMs have batteries (simple and NMC LiIon):

pv_and_storage_facilityexcess.osm (322.7 KB)
storage_liion_battery.osm (79.1 KB)

Developing the mentioned items in the OSM files in IB and HB will help a lot to perform such kind of energy management and energy flexibility.

Thank you very much in advance for your time and assistance.

Sincerely,
Behnam Mohseni Gharyehsafa
Maynooth, Ireland