Z E M C H 2 0 1 2 I n t e r n a t i o n a l C o n f e r e n c e
40
Figure 1: Annual primary energy performance in terms of NZEB performance for case studies
Two of the three projects exhibiting a near zero-energy performance,
Leaf
, was initially
designed to meet net zero-carbon performance (Musall 2012) whereas
Lima
and
Écoterra
, were designed to be energy efficient to minimise negative impact in
environment (Noguchi et al. 2008). One should be mindful that
Lighthouse
, which is a
demonstration building was also designed as net zero-carbon house, being the UK’s first
that also meets Level 6 (the highest level) of the Code for Sustainable Homes
(Department for Communities and Local Government 2009).
One should remark that the selection of the 9 projects was based on criteria such as
access to technical documentation regarding physical characteristics, monitored and/or
simulated energy performance data, as well as lessons learned about designing,
operating, and post-evaluating processes.
NZEB Design Features
Although the main principles applied in passive sustainable design are well known, the
fundamental issue here is to find if the same can be applied in NZEB design as well. To
find out the answer, the analysis of the 9 project buildings was performed according to
the scheme shown in figure 2. As it can be seen in the scheme from figure 2, the first
principle in the NZEB design focuses on reducing the amount of energy needed through
passive approaches, (inner circle of the chart). Given the inherent needs of artificial
lighting and possible heating and/or cooling, the second principle aims at implementing
energy efficient systems, (second circle of the chart). The renewable energy systems are
needed to offset in large measure the energy demand required for lighting, heating and
cooling (the third principle). However, rather than performing a detailed analysis of each
of the projects, a cross examination was performed instead. This procedure is expected
to allow for the identification of the set of relevant NZEB design issues (combination of
passive approaches (PA), energy efficient systems (EES) and renewable energy
