Hybrid system (heat pump and gas boiler)

Dear Ladybug community,

I would like to use honeybee to model a hybrid system that uses a combination of renewable energy and fossil fuels. When the outside air reaches lower temperatures (below zero), the heat pump shuts down and the system switches to the traditional fossil fuel boiler.
I tried to find example of such model but could not. Is it possible to model this using honeybee?

Thank you for your help!


I have thought of one method to model a hybrid system (gas boiler + heat pump) using honeybee:

  • detect when temperature drops below -X degree C using import Stat component;
  • use a dispatch component to switch from heat pump to PTAC system when outdoor temperature gets below -X.
    Is that such method possible? Switching between two different HVAC systems during the modelling process?
    Thank you!

Here is how I would do this:

In LBT 1.5, assign a heating system that has an Air Source Heat Pump (ASHP) on the plant side. A hot water ASHP is much harder to build from scratch in the OpenStudio App or with the OpenStudio SDK. So I’d start with that. Also bear in mind that Legacy Honeybee does not have any built-in HVAC tempaltes for hot water ASHP so you should use LBT.

Then, in the OpenStudio App, you can add a backup Boiler right next to the Hot Water ASHP.

Lastly, you can assign availability schedules to the Boiler and the ASHP to dictate when each is active.

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Thank you Chris! I will give it a try :slight_smile: