BEMGen 1.3.0

BEMGen 1.3.0 is a Grasshopper plugin for Rhino 8 that builds building energy models at several levels of detail.

What's new

• An IDF ready to simulate. Convert2IDF writes an EnergyPlus 26.2 input file (it was 25.2):
  • a new input, Weather, takes the path of an .epw weather file. The IDF gets Site:Location from the file's header, and the header and Provenance name the file with its SHA-256. Without one, EnergyPlus takes the location from the weather file it runs with;
  • hourly outputs: the meters behind heating, cooling, and the total load (only for what the building uses), the zone mean air temperature and ideal-loads heating and cooling of every zone, the annual summary tables, and an SQLite file;
  • ground temperatures of the building's monthly mean indoor setpoint minus 2 °C (20.5 °C with the built-in presets; 18 °C before);
  • non-convex outdoor surfaces, such as the roofs of L-, U-, and court-shaped plans, written as convex pieces of the same area, so that EnergyPlus computes their shadows correctly;
  • a case record in the header that names the building, the zoning, the weather file, and the envelope.
• Unmodelled storeys cast shadows. The storeys that Stacked Floor Zone Multiplier represents but does not model now cast shadows through opaque shading surfaces at their walls, in both converters. In a courtyard plan the wings shade each other again as with every storey modelled. Convert2BEM has a new output, Shading (31).
• Experiment outputs. The developer documentation defines what every simulated case yields and how it is compared with a reference case: annual and peak loads, EUI per conditioned and per total floor area, hourly CV(RMSE), load-duration-curve measures, building temperatures, runtime, and the case record.

Changes that affect existing definitions

• Definitions saved with 1.2.0 or 1.1.0 open as they were, with their values and wires; Weather is unset.
• Definitions saved with 1.0.2 or earlier still lose the infiltration values of their presets when they open, as described for 1.1.0.
• IDF files change: EnergyPlus 26.2, hourly meters instead of monthly ones, more output objects, different ground temperatures, and outdoor surfaces split into convex pieces where they were not convex. Simulate them with EnergyPlus 26.2.
• The example definitions have been rebuilt with 1.3.0.

Install

Close Rhino first. Install BEMGen in one way only, because two copies of BEMGen.gha register the components twice.

• Yak package: drag bemgen-1.3.0-rh8_19-win.yak onto a running Rhino 8.19 (or later) window, then restart Rhino.
• Zip:
  1. Open the properties of bemgen-1.3.0-rh8-win.zip and tick Unblock.
  2. Unpack it and copy the BEMGen folder into %APPDATA%\Grasshopper\Libraries\, so the plugin is at %APPDATA%\Grasshopper\Libraries\BEMGen\BEMGen.gha. If an earlier version is there, replace the whole folder.
  3. Restart Rhino.
• Examples: bemgen-1.3.0-examples.zip holds the example definitions.
• Checksums: SHA256SUMS.txt lists the SHA-256 checksum of each of the three files.

Documentation: https://energy-atlas.github.io/BEMGen-docs/ (see Getting started, and What's new at https://energy-atlas.github.io/BEMGen-docs/user/whats-new/).