Part L2a - 2013 edition

[ecoboost]

Will IES be including green deal with the updated regs?

[Terence]

No, it is not in the plan. As I said in reply to your previous posts on this topic there isn't sufficient demand for the Green Deal at this time but we will be keeping this under review.

[Terence]

Looking at the new SAP document it appears most fuel factors will be changing for Part L 2013. I've created a quick comparison table



These may be slightly different when they are finalised and published in the NCM Modelling Guide.

[ecoboost]

Doesn't really mean much if the notional uses the same fuel, does it?

[Terence]

Not really, for the current regulations in England & Wales if a system serving spaces in the Actual Building uses Electricity (0.517 kgCO2/kWh) as the heating fuel then the equivalent system in the Notional building will use Oil (0.297 kgCO2/kWh).

Going from the proposed new factors for Part L 2013, the benefit of including renewables would be slightly reduced due to the lower CO2 emission factor for Grid Displaced Electricity.

[Terence]

No sign of the NCM Modelling Guide yet, BRE say they will release cSBEM (basically a early development version of iSBEM) this week though.

http://www.2013ncm.bre.co.uk/index.jsp

[Complex Potential]

Thanks for keeping us up to date Terence.

[Complex Potential]

I still haven't seen the new NCM modelling guide . Has anyone got a copy yet?

[Terence]

Draft version of the 2013 NCM modelling Guide is available here: http://www.2013ncm.bre.co.uk/filelibrar ... ec2013.pdf

It was posted along with the following text.

The draft version of the NCM guide is currently being reviewed by stakeholders from Industry before receiving final approval. Further minor modifications may be introduced before the release of the official guide.

Fuel Factors will be as follows:



Summary of changes to Notional building properties

- Notional building Windows U-value reduced from 1.8 to 1.6. Roof light U-value remains 1.8
- Air permeability in the Notional Building now depends on gross internal area and activity.
- Notional building spaces regarded as Top Lit will have a g-value (EN ISO 410) of 0.55, an increase from 0.43 in 2010.
- When the Actual building space heating system uses Gas, Electricity or Oil the ScOP for the Notional equivalent is 86.45%, increased from 79.2%. Biofuels remain the same as in 2010.
- When the Actual building DHW system uses Gas, Electricity or Oil the ScOP for the Notional equivalent is 86.45%, increased from 83.6% in 2010. Biofuels remain the same as in 2010.
- Terminal SFP decreased from 0.5 W/l/s to 0.3 W/l/s
- The Notional building system has variable speed pumps with multiple pressure sensors.
- Where a zone is mechanically ventilated the Notional building will have Demand Control Ventilation.
- Light efficacy has increased from 55 lm/W to 60 lm/W
- All zones in the Notional Building which receive natural daylight will now have photo-electric dimming
- All zones in the Notional Building will now have occupancy sensing based on "Manual-on-Auto-off" with a parasitic power of 0.3 W/m2

[Complex Potential]

Thanks Terence!