Abstract--The smart home contains a network that connects
home elements like sensors, HVAC (heating, ventilation, and air
conditioning), appliances and thermostat. In our previous work,
we proposed an approach that used web services to remotely
interact with smart home elements in a smart grid environment.
These interactions include adjusting the temperature or reading
energy consumption. We assumed a smart home with a wireless
sensor network based on Zigbee. There was a central computer
that could access all home elements. Business Process Execution
Language (BPEL) was used to implement the web service on
central computer. In this paper, we enhance the system by
including new features. The algorithm to sell energy back to the
grid has been further developed. Furthermore, a function to
optimize energy using dynamic programming is added to the
system. The performance and advantage of the communications
between user and home elements via web services are
demonstrated.
Index Terms--dynamic programming; optimization; energy
management; smart grids; smart homes; web services; wireless
sensor network; zigbee.
I. INTRODUCTION
HE smart home is a dwelling incorporating a
communication network that connects electrical elements
(e.g., washer, HVAC (heating, ventilation, and air
conditioning), thermostat) of a home, and allows them to be
remotely controlled, monitored or accessed. Smart homes are
typically used for security, energy management, comfort and
health care. A smart home also contains a smart meter, which
records energy consumption and transmits them wirelessly to
the utility provider.
A Web service (WS) describes a collection of operations
that are accessible via internet through standardized XML
(Extensible Mark-up Language) messaging. WS use XML to
code and decode data and traditionally use SOAP (Simple
Object Access Protocol) to transport it using existing
protocols, like HTTP (Hypertext Transfer Protocol). The main
advantage of WS is its interoperability. The client only
requires the WSDL (Web service description language)
definition to effectively exchange data with the service and
neither part needs to know how the other is implemented.
This work was partially supported by ORF-RE WiSense project.
A. A. Khan and H. T. Mouftah are with School of Electrical Engineering
and Computer Science, University of Ottawa, Ottawa, ON K1N6N5 Canada
(e-mail: akhan083@site.uottawa.ca; mouftah@site.uottawa.ca).
Therefore, it can be accessed by applications running on
different platforms. Furthermore, WS can easily be accessed
over the internet as it uses SOAP and HTTP for
communications. SOAP can get around a firewall. Web
services technologies are a set of technologies based on XML
standards that help describe, access, and interact with WS. WS
Framework consists of three platform elements: WSDL, UDDI
(Universal Description, Discovery and Integration) and SOAP.
WS technology is a XML-centric realization of Service-
oriented architecture (SOA). When a client wants to use the
web service, it searches for the specific service in UDDI.
UDDI returns a WSDL file which describes the web service
and its location. Clients use this information in the WSDL file
to form a SOAP request to the designated computer offering
the service. That computer performs the required operation
and returns result via SOAP.
Smart grid (SG) covers the generation, transmission and
distribution of electricity to consumers. Building the SG means
adding advanced computer and communications technology to
the existing electricity grid and placing a networked sensor
along wires to quickly prevent or locate a problem wirelessly.
SG saves energy, reduces cost, increases reliability and
transparency. Furthermore, it reduces emission of greenhouse
gases and fosters demand response. SG also includes
distributed and renewable generation resources like solar
panels, wind turbine and Plug-in Hybrid Electric Vehicles
(PHEV). These environment-friendly resources will enable a
home to generate, consume, store and then sell energy back to
the grid. The real-time, two-way communications available in
a SG will enable the suppliers to observe the energy
consumption of a house and send information to the consumers
through a smart meter. Thus, SG enables the consumer to be
more involved in order to optimize his energy consumption
[1].
As energy costs are rising, more and more people are
interested to reduce their energy consumption or shift their
load to off-peak hours. The residential consumer wants to
control temperature or appliance to reduce energy cost of
home. Consumer also likes to interact with home devices
remotely for comfort like remotely adjusting temperature or
turning on coffeemaker before arriving home. The consumer
should be able to carry out these functionalities quickly,
remotely and securely. Web Services provide interoperability
and are easily accessed over the Internet. The objective of this
paper is to propose an approach that uses web services to
remotely and efficiently interact with smart home devices to
Energy Optimization and Energy Management
of Home Via Web Services in Smart Grid
Adnan A. Khan, Student Member, IEEE, and Hussein T. Mouftah, Fellow, IEEE
T
2012 IEEE Electrical Power and Energy Conference
978-1-4673-2080-1/12/$31.00 ©2012 IEEE 14