NUI Galway – UL Alliance First Annual ENGINEERING AND - ARAN ...

Dwelling Energy Measurement Procedure
Brendan E. Hoare and Colm V. Cryan PhD.
Civil Engineering and Material Science department
University of Limerick
Brendan.Hoare@ul.ie
Abstract
Abstract – This study presents a building energy
measurement procedure utilising a Zigbee wireless
sensor network. It is presented as an alternative to the
Dwelling Energy Assessment Procedure (DEAP)
yielding the actual energy performance of the building.
The procedure not only takes the design and materials
used into account, but also the standards of
workmanship and current maintenance condition.
1. Introduction
The dwelling energy assessment procedure
(DEAP) is encapsulated in Irish law as the method used
to assess the energy performance of a residential
building. The owner of every building that is sold or
leased is required to provide a building energy rating
(BER) certificate. The BER is calculated by DEAP
based on the design, location and material specifications
of the building. Important parameters such as
workmanship and maintenance condition, which
significantly impact performance, are not considered.
Recent advances in wireless sensor networks
(WSN’s) have enabled the development of noninvasive,
distributed sensor systems. Such systems can
gather data from a large number of nodes and
communicate the information back to a central hub for
analysis. The aim of this project is to explore the use of
such a system to measure the actual thermal
performance of a building: the Dwelling Energy
Measurement Procedure (DEMP.)
An important output of the project is the
determination of a figure of merit for the building that
equates to its actual thermal performance; in a manner
similar to the BER. In addition, it is intended that the
system will allow users to see how the thermal
performance varies from room to room: something
which DEAP does not facilitate.
Having reviewed the hardware and software
requirements for the system and considered a range of
options; the Zigbee standard was selected for this study.
2. Zigbee Standard
Zigbee (IEEE 802.15.4) is an emerging wireless
technology standard, developed by the Zigbee Alliance.
The standard is designed to facilitate the provision of
low-cost, low power, personal area networks. The
standard can support up to 65,000 nodes, operating at
up to 250 kbps. In this study star and mesh network
topologies are being explored and the capabilities and
suitability of each is being assessed.
19
Fig.1: Schematic diagram of a Zigbee mesh topology;
showing coordinator, extender and sensor nodes.
Fig.1. Zigbee Mesh Topology
3. Test Procedure
A range of residential buildings have been selected
as test cases for the investigation. Each building
has been assessed using DEAP and a detailed
inspection of its fabric was performed.
We are currently working in one of the test
case buildings; implementing a wide range of
experiments under tightly controlled conditions.
The results are being analysed to develop methods
to isolate the different parameters that impact its
thermal performance and to determine useful
metrics for the figure of merit.
Once complete each of the case study buildings
will be measured and the resulting figures of merit
compared to the BER ratings calculated via DEAP.
Fig.2. Block diagram of the key configuration
layers of DEMP.
Fig.2. DEMP configuration layers.
4. References
[1] P. Baronti, P. Pillai, W.C. Chook, S. Chessa, A.
Gotta and Y. Fun Hu,”Wireless sensor networks: A
survey on the state of the art and the 802.15.4 and
Zigbee Standards”, Computer Communications 30
(2007) pp. 1655-1695.