IES-VE User Forum

Hi

I am modelling the communal part of some apartment blocks for an SBEM.

They all use electric panel heaters. But when I create what I think is the appropriate 'system' for these using electricity as the fuel and using the NCM system type 'Other local room heater - unfanned', then the notional building uses oil instead when SBEM is run. This has the effect of pushing the primary fuel use and the CO2 emissions of the real building through the roof compared to the notional building, and there is not a chance of getting close to the TER.

There is a FAQ on this; https://www.iesve.com/support/faq/pdf/n ... faq231.pdf

However this refers to a table that does not exist in the current (2013) NCM Modelling Guide. My reading of s26 of the current guide leaves me to believe that the notional building should always match the fuel used in the real building.

Am I reading this correctly? Or am I picking the wrong NCM system type?

The table in the FAQ is pulled from the 2008 NCM Modelling guide and is for the old Part L2a 2006 regulations.

For the current regulations users should reference the 2013 NCM Modelling Guide, table 7 and table 8.

This shows that if the Heating fuel used in the Actual Building is Electricity (direct), then the Heating fuel used by the Notional building is to have a CO2 emission factor of 0.319 kgCO2/kWh. If you look at Table 25 you will see that 0.319 kgCO2/kWh is in fact the fuel factor for Oil.

The fact they tell you a fuel factor and not the fuel name in this table has always left me a bit perplexed

I see that now. Like you say it could be made clearer. Thanks.