rather  than  installing  a  power  monitoring  meter  on 
each device  within  a  building, software can  instead 
analyse and  determine  which  devices  on  a property 
are in use based on the power signatures found within 
an  aggregate  power  data  set  for  an  entire  home,  or 
business.  
Power producers will be able to monitor a home, 
or  business,  and  understand  which  devices  can  be 
cycled  during  peak  loads  to  relieve  grid  pressure, 
especially  in  high  energy  consumption  areas  like 
urban centres where large percentages of a population 
tend to live. In order to accomplish this, a device is 
needed to record a consumer’s power usage. A pilot 
program has been created at the University of Hawai’i 
that  currently involves  monitoring  aggregate  power 
usage from 20 homes on the island of Oahu using a 
smart power meter  (SPM).  The  components, 
challenges and scalability of the pilot system will be 
discussed,  as  well  as  future  work  pertaining  to 
demand response programs, which will be discussed 
in the following sections. 
1.2  Related Research 
The  study  and  feasibility  of  demand  response  as  it 
relates  to  power  grids  is  ongoing,  and  the  pilot 
program  looks  to  contribute  to  that  research  in  the 
areas  of  large  data  collection,  storage  and  analysis 
(FERC 2008, NAERC 2007). 
Demand  response  programs  allow  for  increased 
peak load reduction as well as the ability to balance 
supply and demand of energy in power grids (FERC, 
2008). Stability and load shifting are two factors that 
are important in maintaining grid stability, which can 
be accomplished through demand response programs. 
Cost efficiency is another benefit of demand response 
because there is no need to maintain spinning reserves 
and large power storage infrastructure (NREL 2012). 
Similar research is being done on smart meters to 
collect and analyse data. A group from the University 
of Bath investigated the use of smart metering devices 
in combination with voltage control techniques. Their 
re-search focused on analysing the consumer side of 
demand response as a way to  create  cost  efficiency 
for a consumer as well as a tool to restore grid system 
faults  and  maintain  transmission  stability.  The  Lon 
Local  Operating  System  (LonWorks)  and  ZigBee 
Wireless Network Standard were two suggestions for 
creating  a  system  of  communication  between smart 
meters and controllers to handle real-time data (Gao 
and Redfern, 2011). 
A research group in Europe proposed the use of 
local  area  networks  (LAN)  and  wireless  local  area 
networks  (WLAN)  in  combination  with  KNX 
communication  standards  as  an  option  to  set  up 
communication between smart metering devices. The 
use  of  ZigBee  and  KNX  components  were  deemed 
feasible  to  monitor  load  consumption  of  devices  in 
order to create a timetable of shiftable loads. The load 
shifts refer to the rescheduling of device usage from 
peak hours to times that do not provide large strains 
on  the  grid.  Real-time  analysis  and  visualization 
would allow consumers to make the proper choices in 
energy  consumption  that  are  related  to  cost 
efficiency.  An  algorithm  based  on  tariffs  was  the 
basis for the load timetables (Kunold et al., 2011). 
Researchers in Canada proposed a smart metering 
system based on load disaggregation where a power 
signal is analysed into the various device components 
that produce it. Their research focused on the factors 
that affect load disaggregation such as noisy signals, 
simultaneous  loading,  computational  costs  and 
privacy  issues.  They  noticed  that  devices  produced 
different  power  signals  when  cycled,  for  example, 
constant  vs.  periodic  loads.  To  train  algorithms  in 
detecting  a  device,  the  research  group  suggested 
algorithm  training  based  on  probabilities  and  the 
clustering of individual devices. The research group 
deemed  the  definition  of  deferrable  actions  as 
necessary  in  their  proposed  system.  Deferrable 
actions are those relating to devices whose utilization 
is not a priority and cycling can instead be scheduled 
at  an  alternative  time,  which  would  allow  for  load 
shedding.  These  devices  include  washer/dryers, 
ovens and dishwashers (Makonin, 2013).  
A UK-based power utility, National Grid, looked 
into the affect the power usage of certain devices had 
on  the  grid.  They  found  that  millions  of  kettles  are 
cycled around 5pm, knowledge such as this allows a 
utility  to  know  when  to  cycle  specific  loads  within 
home.  National  Grid  uses  the  aforementioned 
knowledge to maintain grid frequency. Aggregating 
these cycling patterns with the loads of other houses 
in a neighbourhood, or region, allow for the ability to 
maintain grid stability throughout sections of a power 
grid (National Grid, 2015). 
2  SPM PILOT SYSTEM 
Because  of  the  island’s  geography  and  dense 
population,  Oahu  provides  an  ideal  location  to 
understand  renewable  energy  penetration  into  an 
existing  power  grid,  and  how  it  relates  to  demand 
response programs. Several factors allow for Oahu to 
be the location to implement the pilot system, these 
factors  include  high  solar  radiation  on  the  island, 
access to a dense urban populations, and Oahu being