Hi Brett - the BC Step Code Calculator has a conversion from GJ/year to GHG. You can use that as a rough estimate, which includes estimations for both Proposed and Reference home GHG/year.
if you have a Hot2000 file you can extract the proposed GHG using the Step Code calculator, which is just a matter of hitting a button on the spreadsheet.
The link is here:
https://energystepcode.ca/compliance-tools-part9/