ORCalc
ORCalc is the name of the UK government-mandated software which is used to generate Display Energy Certificate (DEC) and Advisory Reports for buildings in the UK. ORCalc stands for Operational Rating (OR) calculation because it is based on a buildings actual operation energy consumption data.
This is as opposed to for example Energy Performance Certificates (EPCs) which look very similar but are generated using modelled building energy based either the Standard Assessment Procedure (SAP) methodology or Simplified Building Energy Model (SBEM) and a variety of assumptions.
It can be downloaded for free but is primarily used by energy assessors who are qualified and competent in the use of the software to produce DECs.
For further information visit: Guidance Display Energy Certificates and advisory reports for public buildings
aswell as https://www.uk-ncm.org.uk/index.jsp or https://www.ncm-pcdb.org.uk/sap/page.jsp?id=7
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