W h i c h i s t h e B e s t T o o l t o A s s e s s Z e r o E n e r g y H o u s i n g ?
187
WHICH IS THE BEST TOOL TO ASSESS ZERO ENERGY
HOUSING?
Richard Atkins
1
& Rohinton Emmanuel
2
1
Dept. of Construction and Surveying, School of Engineering and Built Environment, Glasgow Caledonian
University, Scotland,
2
Dept. of Construction and Surveying, School of Engineering and Built Environment, Glasgow Caledonian
University, Scotland,
Abstract
In 2007 the Scottish Government published the Sullivan Report which recommended
that the Technical Handbooks to the Scottish Building Standards should be revised
progressively to require all new buildings in Scotland to achieve “
Net zero carbon
buildings (i.e. space and water heating, lighting and ventilation) by 2016/2017, if
practical
”. This paper briefly describes 3 calculation methodologies used in the UK
comparing the inclusions, algorithms and assumptions within each. The interplay
between calculation methodologies and standards, the debate surrounding the definition
of zero energy housing, the need for calibration and speculate on the role of Building
Information Models (BIM) software in providing a frame work to close the loop.
Keywords:
Zero Energy, CO
2
emissions, SAP, SBEM, PHPP, CAD, BIM.
Introduction
The Energy Performance of Buildings Directive (EPBD) 2002/91/EC requires member
states to introduce standards to promote and improve energy efficiency in buildings. The
EPBD has five strands. These are the requirement for assessing energy use using
consistent methods, the requirement to provide Energy Performance Certificates (EPCs),
the requirement to inspect boilers, as well as air conditioning systems and the
requirement to introduce standards over time that require improvement. An annex to the
EPBD defines a minimum of 8 factors that must be considered in any NCM:
1.
Thermal performance of the building envelope
2.
Heating and hot water systems
3.
Air conditioning systems
4.
Natural and mechanical ventilation
5.
Artificial lighting
6.
Climate and orientation
7.
Passive solar systems and shading
8.
Indoor climate
The NCM must also take into account the reduction in energy requirement from on site
renewable electricity generation, combined heat and power (CHP) systems, district
heating and/or cooling systems and natural lighting.
To demonstrate compliance with the Building Codes in Scotland Clause 6.1.1 of the
Scottish Building Standards Technical Handbook (Oct 2011 version) requires that a
Domestic Emissions Rating (DER) is calculated for new dwellings, which must be ≤ a
Target Emissions Rating (TER) using the UK NCM. For new dwellings this is currently
the Standard Assessment Procedure (SAP) 2009. The TER is based on a notional
