Energy saving using zigbee

7/25/2019 Energy saving using zigbee

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Abstract

As home energy use is increasing and renewable energy systems are deployed, homeenergy management system (HEMS) needs to consider both energy consumption and gen-eration simultaneously to minimize the energy cost. This seminar proposes a smart HEMS

architecture that considers both energy consumption and generation simultaneously. ZigBeebased energy measurement modules are used to monitor the energy consumption of homeappliances and lights. A PLC based renewable energy gateway is used to monitor the en-ergy generation of renewable energies. The home server gathers the energy consumptionand generation data, analyzes them for energy estimation, and controls the home energy useschedule to minimize the energy cost. The remote energy management server aggregatesthe energy data from numerous home servers, compares them, and creates useful statisticalanalysis information. By considering both energy consumption and generation, the proposedHEMS architecture is expected to optimize home energy use and result in home energy costsaving.

Index Terms : Home Energy Management System, ZigBee, Renewable Energy, PowerLine Communication

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Contents

Abstract i

Contents ii

List of Figures iv

1 Introduction 1

2 Literature Review 3

3 Energy Management 53.1 Smart Home Energy Management System . . . . . . . . . . . . . . . . . . . 6

4 Zigbee Technology 84.1 Zigbee Modem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.2 Zigbee Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94.3 Zigbee System Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.4 Zigbee Operating Modes and Its Topologies . . . . . . . . . . . . . . . . . . 104.5 Applications of Zigbee Technology . . . . . . . . . . . . . . . . . . . . . . . . 12

5 Components of Home Energy Management System Including RenewableEnergy 135.1 Energy Management and Communication Unit (EMCU) . . . . . . . . . . . 135.2 Zigbee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135.3 Solar Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.4 Wind Turbine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155.5 Solar Inverter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155.6 Smart Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

5.7 Power-line Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175.8 Solar Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

5.8.1 Concentrating Solar Power . . . . . . . . . . . . . . . . . . . . . . . . 185.9 Wind Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205.10 A Typical Wind Turbine Consists of The Following Components: . . . . . . 215.11 Wind Energy Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

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6 System Discription 236.1 System Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236.2 Home Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246.3 Energy Management and Communication Unit (EMCU) . . . . . . . . . . . 256.4 Renewable Energy Gateway and PLC Modem . . . . . . . . . . . . . . . . . 26

6.5 Remote Energy Management Server (REMS) . . . . . . . . . . . . . . . . . . 26

7 Application 28

8 Conclusion 298.1 Future Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Bibliography 30

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List of Figures

4.1 Zigbee modem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.2 Zigbee protocol architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.3 Zigbee Communication Operation . . . . . . . . . . . . . . . . . . . . . . . . 104.4 Comparison Table of Zigbee . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

5.1 Zigbee module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5.2 Solar panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.3 Wind turbine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155.4 Solar inverter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165.5 smart meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165.6 Parabolic Trough . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185.7 Solar Tower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195.8 Linear Fresnel Reactor (LFR) . . . . . . . . . . . . . . . . . . . . . . . . . . 195.9 Solar Dish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205.10 Typical Wind Turbine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.1 Architecture of smart home energy management (HEMS) considering both

energy consumption and generation . . . . . . . . . . . . . . . . . . . . . . 236.2 Function blocks of a home server . . . . . . . . . . . . . . . . . . . . . . . . 256.3 Energy measurement and communication unit (EMCU) and protocol stack. . 266.4 Architecture of a renewable energy gateway (REG) and a PLC modem. . . . 276.5 Remote energy management server (REMS) connected to the home servers of

subscr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

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Chapter 1

Introduction

Continuous increase in global energy consumption gives rise to the current energy crisesand the environmental problem. Residential energy consumption accounted 22 percent of UStotal energy consumption in 2009. The increasing number of home appliances and consumer

electronics causes the growth of home energy use. Therefore, reducing energy use in homes isa very challenging target to mitigate the energy crisis and the environmental problem. Thetechnology to reduce and manage home energy use is known as home energy managementsystem.

The current energy crisis has required significant energy reduction in all areas. The energyconsumption in home areas has increased as more home appliances are installed. Energysaving and renewable energy sources are considered as methods of solving home energyproblem. Both energy consumption and generation should be simultaneously considered tosave the home energy cost.

Now a days in home areas world most considerable topic is energy saving and generation

of power by smart home energy management system by using solar panel and wind turbine.Usage of wireless devices is increasing day by day so this application helps us to know theenergy consumption and generation. Energy management systems can be used to controldevices like lighting systems and High Voltage Alternating Current units across multiplelocations, such as office buildings, grocery, retail, restaurants sites. Energy managementsystems also provide metering and monitoring functions, which allows them to take decisionsregarding energy activities across their sites. Energy management includes planning andenergy related production and consumption units.

The current energy crisis requires significant reduction in energy consumption in all areas.Energy saving and renewable energy sources (RES) are considered as methods of solving theproblem. In home area, the increasing number of home appliances and consumer electronics

causes residential energy use to grow rapidly. Optimized home energy management system(HEMS) is needed to reduce energy use and save money. Optimization of home powerconsumption based on power line communication (PLC) has been studied. A HEMS thatmonitors, compares, and controls home appliances has been proposed.In addition, RES suchas a photo voltaic energy system and wind energy system are deployed to conserve residentialenergy use and to reduce energy cost. Energy management systems including renewableenergy have been studied to advance smart home. In this paper, we propose smart homeenergy management system including renewable energies based on ZigBee and PLC networks

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to optimize home energy use. The home server gathers both the energy consumption datathrough ZigBee and energy generation data through the REG. By taking into account bothconsumption and generation, the home server optimizes home energy use.

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Chapter 2

Literature Review

Smart buildings and homes are becoming a key player in the future green and sustain-able energy grid, due to the integration of distributed energy sources and the demand controlcapabilities. Advanced smart metering systems are required for the operation of the future

smart grid. Smart metering systems allow to monitor the energy consumption of end-users,while provides useful information regarding power quality. The information provided bythese systems is used by the system operator to enhance the energy supply, and several tech-niques, as load scheduling, demand side management, non-intrusive load monitoring, can beapplied for this purpose. This seminar shows an advanced smart metering infrastructure forintegration in future smart homes, where not only the electrical consumption is monitored,but also the gas, water, and heating. Therefore, by monitoring all energy systems in thebuilding, the users could be aware of their whole energy consumption, and advanced controltechniques can achieved by the Energy Management Systems (EMS).[1]

This seminar describes a home energy management system (HEMS) based on power

line communication. Smart metering and power line communication can provide detailedinformation of energy consumption patterns and intelligent controlling to appliances at home.This reference propose a HEMS that can provide easy-to-access information on home energyconsumption in real time, intelligent planning for controlling appliances, and optimizationof power consumption at home. The HEMS consists of three modules: an advanced powercontrol planning engine, a device control module, and a power resource management server.Our prototype system reduces the cost of power consumption by about 10 percent [2]

Home Energy Management System (HEMS) is a technology to reduce and manage homeenergy use. The feedback on energy consumption to energy users is known to be effectiveto reduce total energy use. A typical HEMS just shows the energy consumption of thewhole home and home appliances. Users cannot figure out how efficient a home appliance is,

compared to the others. So it is necessary to compare the energy usage of home appliancesto that of the same kinds of home appliances.[3]

To inculcate the Home Energy Management System (HEMS) based on ZigBee communi-cation using remote controller and sensor. This technique brings out the more efficient homeenergy management system to reduce power consumption in home area. This reference con-sider the room easily controllable with an IR remote control of a home appliance. The roomhas power outlets, a light, sensor and a ZigBee hub. The ZigBee hub has an IR code learningfunction and educates the IR remote control signal of a home appliance connected to the

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power outlet. Then it can control the power outlets and the light in the room. The PIRsensor which detects the presence of the human and then it allows the power on the light..A LCD is used in the hardware module for the user interface. The LCD displays the powerconsumed and the value of PIR sensor. The ZigBee hubs in each room communicate withthe home server and report the power consumption information to the home server. The

proposed architecture gives more efficient energysaving HEMS. [4]As the numbers of large-sized electric home appliances are increasing, the home en-

ergy consumption is also increasing proportionally. To reduce the home energy cost, it isnecessary to consider both energy consumption and generation. In this application intel-ligent home uses renewable energies. The problems of home energy management systemsare solved by implementing energy saving method and renewable energy sources. Energysources are connected to the grid via battery and inverter, the output of battery is connectedto microcontroller. For displaying the battery voltage and availability of energy source mi-crocontroller is connected to LCD. Some units will be consumed whenever load is connected,consumed units will be calculated with the help of microcontroller and it is displayed on theLCD.[5]

A low-power programmable processor named icyflex1 was designed combining featuresof a digital signal processor (DSP) and a micro-controller unit (MCU). Implemented as asynthesizable VHDL software intellectual property core, the processor implements a broadrange of power saving features including its customizable architecture and reconfigurableinstruction set. Its performance is compared with other processors from the market andvalues are given for its integration in a 180 nm technology. The processor targets applica-tions with tight power consumption constraints and correspondingly significant processingperformance.[6]

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Chapter 3

Energy Management

Energy management is a term that has a number of meanings, but were mainlyconcerned with the one that relates to saving energy in businesses, public-sector/governmentorganizations, and homes.

The energy-saving meaningWhen it comes to energy saving, energy management is the process of monitoring, con-

trolling, and conserving energy in a building or organization. Typically this involves thefollowing steps

1. Metering your energy consumption and collecting the data.

2. Finding opportunities to save energy, and estimating how much energy each oppor-tunity could save. You would typically analyze your meter data to find and quantifyroutine energy waste, and you might also investigate the energy savings that you couldmake by replacing equipment (e.g. lighting) or by upgrading your buildings insulation.

3. Taking action to target the opportunities to save energy (i.e. tackling the routine wasteand replacing or upgrading the inefficient equipment). Typically youd start with thebest opportunities first.

4. Tracking your progress by analyzing your meter data to see how well your energy-savingefforts have worked.

Its not just about saving energy in buildings - the term energy management is alsoused in other fields:

Its something that energy suppliers (or utility companies) do to ensure that their

power stations and renewable energy sources generate enough energy to meet demand(the amount of energy that their customers need).

Its used to refer to techniques for managing and controlling ones own levels of personalenergy. Were far from qualified to say anything more about this!

It also has relevance in aviation its a skill that aircraft pilots learn in some shapeor form. We know nothing about aircraft energy management, but we can at leastmanage a picture of a man on a plane...

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3.1 Smart Home Energy Management System

The concept of home energy management system has been an interesting topic forresearchers and practitioners during the last few years. The majority for recent techniquesconcentrate on exploiting wireless communications on the way to make communicate with

the other devices such as Mobile phones and Laptops.Mostly Smart HEMS architectures are prepared by using the renewable energies and

PLC controller. The energy readings are taken by the smart meter sometimes they preferreddigital meters. This be prepared the smart home energy management system implementationcost is higher as PLC controller is cost wise higher than embedded controllers reminiscentof 8051, PIC, ARM.

Controllers are interface with the Bluetooth for display the reading in mobile phones andLaptops. But the bluetooth range is short then it cannot send the reading informations forlonger distance. Now-a-days there are lots of techniques used to send the data for longerduration. One of the far and wide used techniques is internet.

Zigbee based Smart home energy management system are integrated with Wi-Fi network

through gateway. Gateway can provide the user interface and openness to the particularsystem. Through using Zigbee designed for take the electrical readings such as energy con-sumption from home appliances.

A system via the Global System for Mobile communications (GSM) and Internet wasproposed for real-time monitoring and remote control in home appliances to display the en-ergy readings. These add flexibility for the implemented system, but, it increases the costwhen using GSM technology. The designing system also exploits Internet for monitor thehome energy also from outside.

Why is it important?

Energy management is the key to saving energy in your organization. Much of the im-portance of energy saving stems from the global need to save energy - this global need affectsenergy prices, emissions targets, and legislation, all of which lead to several compelling rea-sons why you should save energy at your organization specifically.

The global need to save energy.If it wasnt for the global need to save energy, the term energy management might

never have even been coined... Globally we need to save energy in order to:

Reduce the damage that were doing to our planet, Earth. As a human race we wouldprobably find things rather difficult without the Earth, so it makes good sense to try

to make it last.

Reduce our dependence on the fossil fuels that are becoming increasingly limited insupply.

Controlling and reducing energy consumptionEnergy management is the means to controlling and reducing your organizations energy

consumption... And controlling and reducing your organizations energy consumption isimportant because it enables you to:

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Reduce costs this is becoming increasingly important as energy costs rise.

Reduce carbon emissions and the environmental damage that they cause - as well asthe cost-related implications of carbon taxes and the like, your organization may bekeen to reduce its carbon footprint to promote a green, sustainable image. Not least

because promoting such an image is often good for the bottom line. Reduce risk the more energy you consume, the greater the risk that energy price

increases or supply shortages could seriously affect your profitability, or even make itimpossible for your business/organization to continue. With energy management youcan reduce this risk by reducing your demand for energy and by controlling it so as tomake it more predictable.

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Chapter 4

Zigbee Technology

What is Zigbee Technology?Zigbee communication is specially built for control and sensor networks on IEEE

802.15.4 standard for wireless personal area networks (WPANs), and it is the product from

Zigbee alliance. This communication standard defines physical and Media Access Control(MAC) layers to handle many devices at low-data rates. These Zigbees WPANs operateat 868 MHz, 902-928MHz and 2.4 GHz frequencies. The data rate of 250 kbps is bestsuited for periodic as well as intermediate two way transmission of data between sensors andcontrollers.

Figure 4.1: Zigbee modem

4.1 Zigbee ModemZigbee is low-cost and low-powered mesh network widely deployed for controlling and

monitoring applications where it covers 10-100 meters within the range. This communicationsystem is less expensive and simpler than the other proprietary short-range wireless sensornetworks as Bluetooth and Wi-Fi. Zigbee supports different network configurations formaster to master or master to slave communications. And also, it can be operated indifferent modes as a result the battery power is conserved. Zigbee networks are extendable

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with the use of routers and allow many nodes to interconnect with each other for building awider area network

4.2 Zigbee Architecture

4.3 Zigbee System Structure

Zigbee system structure consists of three different types of devices such as Zigbeecoordinator, Router and End device. Every Zigbee network must consist of at least onecoordinator which acts as a root and bridge of the network. The coordinator is responsiblefor handling and storing the information while performing receiving and transmitting dataoperations. Zigbee routers act as intermediary devices that permit data to pass to and frothrough them to other devices. End devices have limited functionality to communicate withthe parent nodes such that the battery power is saved as shown in the figure. The numberof routers, coordinators and end devices depends on the type of network such as star, treeand mesh networks.

Zigbee protocol architecture consists of a stack of various layers where IEEE 802.15.4is defined by physical and MAC layers while this protocol is completed by accumulating

Zigbees own network and application layers.Physical Layer: This layer does modulation and demodulation operations up on trans-

mitting and receiving signals respectively. This layers frequency, date rate and number ofchannels are given below.

MAC Layer: This layer is responsible for reliable transmission of data by accessingdifferent networks with the carrier sense multiple access collision avoidance (CSMA). Thisalso transmits the beacon frames for synchronizing communication.

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Figure 4.2: Zigbee protocol architecture

Network Layer: This layer takes care of all network related operations such as networksetup, end device connection and disconnection to network, routing, device configurations.

Application Support Sub-Layer: This layer enables the services necessary for Zigbee

device object and application objects to interface with the network layers for data managingservices. This layer is responsible for matching two devices according to their services andneeds.

Application Framework: It provides two types of data services as key value pair andgeneric message services. Generic message is a developer defined structure, whereas the keyvalue pair is used for getting attributes within the application objects. ZDO provides aninterface between application objects and APS layer in Zigbee devices. It is responsible fordetecting, initiating and binding other devices to the network.

4.4 Zigbee Operating Modes and Its Topologies

Figure 4.3: Zigbee Communication Operation

Zigbee two way data is transferred in two modes: Non-beacon mode and Beaconmode. In a beacon mode, the coordinators and routers continuously monitor active state of

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incoming data hence more power is consumed. In this mode, the routers and coordinators donot sleep because at any time any node can wake up and communicate. However, it requiresmore power supply and its overall power consumption is low because most of the devices arein an inactive state for over long periods in the network.

In a beacon mode, when there is no data communication from end devices, then the

routers and coordinators enter into sleep state. Periodically this coordinator wakes up andtransmits the beacons to the routers in the network. These beacon networks are work fortime slots which means, they operate when the communication needed results in lower dutycycles and longer battery usage. These beacon and non-beacon modes of Zigbee can manageperiodic (sensors data), intermittent (Light switches) and repetitive data types.

Zigbee TopologiesZigbee supports several network topologies; however, the most commonly used config-

urations are star, mesh and cluster tree topologies. Any topology consists of one or morecoordinator. In a star topology, the network consists of one coordinator which is responsiblefor initiating and managing the devices over the network. All other devices are called enddevices that directly communicate with coordinator. This is used in industries where all theend point devices are needed to communicate with the central controller, and this topologyis simple and easy to deploy.

In mesh and tree topologies, the Zigbee network is extended with several routers wherecoordinator is responsible for staring them. These structures allow any device to communi-cate with any other adjacent node for providing redundancy to the data. If any node fails,the information is routed automatically to other device by these topologies. As the redun-dancy is the main factor in industries, hence mesh topology is mostly used. In a cluster-treenetwork, each cluster consists of a coordinator with leaf nodes, and these coordinators areconnected to parent coordinator which initiates the entire network.

Due to the advantages of Zigbee technology like low cost and low power operating modes

and its topologies, this short range communication technology is best suited for severalapplications compared to other proprietary communications, such as Bluetooth, Wi-Fi, etc.some of these comparisons such as range of Zigbee, standards, etc., are given below.

Figure 4.4: Comparison Table of Zigbee

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4.5 Applications of Zigbee Technology

Industrial Automation: In manufacturing and production industries, a communica-tion link continually monitors various parameters and critical equipments. Hence Zigbee

considerably reduce this communication cost as well as optimizes the control process forgreater reliability.

Home Automation: Zigbee is perfectly suited for controlling home appliances remotelyas a lighting system control, appliance control, heating and cooling system control, safetyequipment operations and control, surveillance, and so on. Smart Metering: Zigbee remoteoperations in smart metering include energy consumption response, pricing support, securityover power theft, etc.

Smart Grid monitoring: Zigbee operations in this smart grid involve remote temper-ature monitoring, fault locating, reactive power management, and so on.

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Chapter 5

Components of Home EnergyManagement System IncludingRenewable Energy

5.1 Energy Management and Communication Unit (EMCU

In the energy consumption part, the EMCU is a key component; it is composedof measurement and communication blocks. The measurement block measures the power,energy, and power factor of plugged home appliances. It uses an energy metering IC formeasuring them. The metering IC measures the voltage and current in a sample period; itmultiplies them; it integrates them continuously. The power and energy is calculated withthis process. The power factor is measure based the phase difference between voltage andcurrent. The measurement block stores only the accumulated energy data at a memory;

it calculates the power and power factor on demand in real time. The measurement blockincludes the power control block that supplies or blocks the electricity to connected homeappliances.

5.2 Zigbee

It is the wireless device for transmitting and receiving data purpose or simply it calledas Transceiver. Zigbee is based on the IEEE802.15.4 protocol. The range of the Zigbeeis covered as 100m. It range is 10 times better than bluetooth device so it can be morepreferable one in wireless device. The data rate is very low for transmission while using

this device. The communication block supports data transfer between the EMCU and thehome server. It adopts ZigBee and IEEE 802.15.4 wireless personal area network (WPAN)as communication methods. It transfers not only the measured energy, power, and powerfactor but also the voltage and current.

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Figure 5.1: Zigbee module

5.3 Solar Panel

A solar panel is consists of many Photo voltaic cells. It used to absorb the sun rays at

day time and take a backup for use it night time. In today world the usage of the solar panelis very high to reduce the power consumption. To increasing the power generation in solarpanel by using Maximum Power Point Tracking Technique. This technique can be simplydone by using two LDR and a DC motor.

Photovoltaic (PV) solar panels are made up of many solar cells. Solar cells are made ofsilicon, like semiconductors. They are constructed with a positive layer and a negative layer,which together create an electric field, just like in a battery. When photons hit a solar cell,they knock electrons loose from their atoms. If conductors are attached to the positive andnegative sides of a cell, it forms an electrical circuit. When electrons flow through such acircuit, they generate electricity. Multiple cells make up a solar panel, and multiple panels(modules) can be wired together to form a solar array. The more panels you can deploy, themore energy you can expect to generate.

Figure 5.2: Solar panel

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5.4 Wind Turbine

Wind turbine is used to absorb the wind from atmosphere and using the kinetic energyfrom wind to generate the electrical power. Battery with Charge controller: Here 12v batterycan be used to store the power from wind turbine and solar panel. Both can produce above

ranges then it can be controlled by using Charge controller circuit. Here a NPN transistorshould be used to provide the safety purpose for drive the power from renewable energyto battery supply and maintain to dont send the power from battery to renewable energysources such as solar panel and wind turbine.

Figure 5.3: Wind turbine

5.5 Solar Inverter

A solar inverter, or converter or PV inverter, converts the variable direct current (DC)output of a photovoltaic (PV) solar panel into a utility frequency alternating current (AC)that can be fed into a commercial electrical grid or used by a local, off-grid electrical network.It is a critical balance of system (BOS)component in a photovoltaic system, allowing the useof ordinary AC-powered equipment. Solar power inverters have special functions adapted foruse with photovoltaic arrays, including maximum power point tracking and anti-islandingprotection.

Solar inverters may be classified into three broad type

1. Stand-alone inverters:used in isolated systems where the inverter draws its DC energy

from batteries charged by photovoltaic arrays. Many stand-alone inverters also incor-porate integral battery chargers to replenish the battery from an AC source, whenavailable. Normally these do not interface in any way with the utility grid, and assuch, are not required to have anti-islanding protection.

2. Grid-tie inverters: which match phase with a utility-supplied sine wave. Grid-tie in-verters are designed to shut down automatically upon loss of utility supply, for safetyreasons. They do not provide backup power during utility outages.

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Figure 5.4: Solar inverter

3. Battery backup inverters: are special inverters which are designed to draw energy froma battery, manage the battery charge via an onboard charger, and export excess energyto the utility grid. These inverters are capable of supplying AC energy to selected loadsduring a utility outage, and are required to have anti-islanding protection.

5.6 Smart Meter

A Smart meter is an electronic device that records consumption of electric energy inintervals of an hour or less and communicates that information at least daily back to theutility for monitoring and billing. Smart meters enable two-way communication betweenthe meter and the central system. Unlike home energy monitors, smart meters can gatherdata for remote reporting. Such an advanced metering infrastructure (AMI) differs fromtraditional automatic meter reading (AMR) in that it enables two-way communicationswith the meter.

Figure 5.5: smart meter

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5.7 Power-line Communication

Power-line communication (PLC) is a communication protocol that uses electricalwiring to simultaneously carry both data, and Alternating Current (AC) electric powertransmission or electric power distribution. It is also known as power-line carrier, power-

line digital subscriber line (PDSL), mains communication, power-line telecommunications,or power-line networking (PLN). A wide range of power-line communication technologies areneeded for different applications, ranging from home automation to Internet access whichis often called broadband over power lines (BPL). Most PLC technologies limit themselvesto one type of wire (such as premises wiring within a single building), but some can crossbetween two levels (for example, both the distribution network and premises wiring). Typ-ically transformers prevent propagating the signal, which requires multiple technologies toform very large networks. Various data rates and frequencies are used in different situations.

A number of difficult technical problems are common between wireless and power-linecommunication, notably those of spread spectrum radio signals operating in a crowded envi-ronment. Radio interference, for example, has long been a concern of amateur radio groups.

Types of PLCPLC can be broadly grouped as narrowband PLC and broadband PLC, also known as

low frequency and high frequency respectively. They may also be grouped as AC or DC.Functionally, there are four basic forms of power line communications:

Narrowband in-house applications: where household wiring is used for low bit rateservices like home automation and intercoms.

Narrowband outdoor applications. These are mainly used by the utility companies forautomatic meter reading and remote surveillance and control.

Broadband In-house mains power wiring can be used for high speed data transmissionfor home networking.

5.8 Solar Energy

solar energy is radiant light and heat from the Sun that is harnessed using a range ofever-evolving technologies such as solar heating, photovoltaics, solar thermal energy, solararchitecture and artificial photosynthesis. It is an important source of renewable energy andits technologies are broadly characterized as either passive solar or active solar dependingon how they capture and distribute solar energy or convert it into solar power. Active so-

lar techniques include the use of photovoltaic systems, concentrated solar power and solarwater heating to harness the energy. Passive solar techniques include orienting a buildingto the Sun, selecting materials with favorable thermal mass or light-dispersing properties,and designing spaces that naturally circulate air.The large magnitude of solar energy avail-able makes it a highly appealing source of electricity. The United Nations DevelopmentProgramme in its 2000 World Energy Assessment found that the annual potential of solarenergy was 1,57549,837 exajoules (EJ). This is several times larger than the total world en-ergy consumption, which was 559.8 EJ in 2012. In 2011, the International Energy Agency

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said that the development of affordable, inexhaustible and clean solar energy technologieswill have huge longer-term benefits. It will increase countries energy security through re-liance on an indigenous, inexhaustible and mostly import-independent resource, enhancesustainability, reduce pollution, lower the costs of mitigating global warming, and keep fossilfuel prices lower than otherwise. These advantages are global. Hence the additional costs of

the incentives for early deployment should be considered learning investments; they must bewisely spent and need to be widely shared. Solar power is the conversion of sunlight intoelectricity, either directly using photovoltaics (PV), or indirectly using concentrated solarpower (CSP). CSP systems use lenses or mirrors and tracking systems to focus a large areaof sunlight into a small beam. PV converts light into electric current using the photoelectriceffect.

Solar power is anticipated to become the worlds largest source of electricity by 2050,with solar photovoltaics and concentrated solar power contributing 16 and 11 percent to theglobal overall consumption, respectively. Commercial CSP plants were first developed in the1980s. Since 1985 the eventually 354 MW SEGS CSP installation, in the Mojave Desertof California, is the largest solar power plant in the world. Other large CSP plants includethe 150 MW Solnova Solar Power Station and the 100 MW Andasol solar power station,both in Spain. The 250 MW Agua Caliente Solar Project, in the United States, and the 221MW Charanka Solar Park in India, are the worlds largest photovoltaic plants. Solar projectsexceeding 1 GW are being developed, but most of the deployed photovoltaics are in smallrooftop arrays of less than 5 kW, which are connected to the grid using net metering and/ora feed-in tariff. In 2013 solar generated less than 1 of the worlds total grid electricity.

5.8.1 Concentrating Solar Power

In Concentrating Solar Power (CSP) plants use Mirrors to concentrate sunlight sun

light on to receiver, which collects and transfers the solar energy to a heat transfer fluid(synthetic oil) that can be used to supply heat for end- use applications or to produce super-heated steam that drives a Rankine cycle steam turbine connected to an electricity generatorto generate electricity. Unlike solar photo-voltaics (PV), CSP uses only the direct componentof sunlight and provides heat and power only in regions with high DNI.

Classification of CSP1. Parabolic TroughParabolic trough-shaped mirror reactors are used to concentrate

sunlight on to thermally efficient receiver tubes placed in the trough focal line.

Figure 5.6: Parabolic Trough

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2. Solar Tower A circular array of heliostats (large individually-tracking mirrors) isused to concentrate sunlight on to a central receiver mounted at the top of a tower.

Figure 5.7: Solar Tower

3. Linear Fresnel Reactor (LFR)A Linear Fresnel Reactor (LFR) array is a line focus system similar to parabolic troughs

in which solar radiation is concentrated on an elevated inverted linear absorber using anarray of nearly at reactors

Figure 5.8: Linear Fresnel Reactor (LFR)

4. Solar DishA parabolic dish-shaped reactor is used to concentrate sunlight on to areceiver located at the focal point of the dish.

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Figure 5.9: Solar Dish

5.9 Wind Energy

Wind energy is a form of solar energy. Wind energy (or wind power) describes the

process by which wind is used to generate electricity. Wind turbines convert the kineticenergy in the wind into mechanical power. A generator can convert mechanical power intoelectricity. Mechanical power can also be utilized directly for specific tasks such as pumpingwater. The US DOE developed a short wind power animation that provides an overview ofhow a wind turbine works and describes the wind resources in the United States.

Figure 5.10: Typical Wind Turbine

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5.10 A Typical Wind Turbine Consists of The Follow-

ing Components:

The TowerTowers are mostly cylindrical, made of steel, painted light grey, and from 25 to 75 metres

in height.Rotor Blades

Wind turbines can have from one to three rotor blades, made of fibreglass-reinforcedpolyester or wood-epoxy. The blades are usually between 30 and 80 metres in diameter.The longer the blades, the greater the energy output. They rotate at 10-30 revolutions perminute at constant speed, although an increasing number of machines operate at a variablespeed. The blades can be rotated to change the pitch angle and modify power output.

The Yaw MechanismThe yaw mechanism turns the turbine to face the wind.Wind Speed and Direction Monitor

Sensors are used to monitor wind direction and the tower head is turned to line up withthe wind. Power is controlled automatically as wind speed varies and machines are stoppedat very high wind speeds to protect them from damage.

The Gear BoxMost wind turbines have gearboxes, although there are increasing numbers with direct

drives.

5.11 Wind Energy Basics

Wind is caused by the uneven heating of the atmosphere by the sun, variations inthe earths surface, and rotation of the earth. Mountains, bodies of water, and vegetationall influence wind flow patterns,Wind turbines convert the energy in wind to electricity byrotating propeller-like blades around a rotor. The rotor turns the drive shaft, which turnsan electric generator. Three key factors affect the amount of energy a turbine can harness

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from the wind: wind speed, air density, and swept area.

Equation for Wind Power

Wind speedThe amount of energy in the wind varies with the cube of the wind speed, in other words,

if the wind speed doubles, there is eight times more energy in the wind ( ).Small changes in wind speed have a large impact on the amount of power available in thewind .

Density of the airThe more dense the air, the more energy received by the turbine. Air density varies with

elevation and temperature. Air is less dense at higher elevations than at sea level, and warmair is less dense than cold air. All else being equal, turbines will produce more power atlower elevations and in locations with cooler average temperatures.

Swept area of the turbineThe larger the swept area (the size of the area through which the rotor spins), the more

power the turbine can capture from the wind. Since swept area is , where r = radiusof the rotor, a small increase in blade length results in a larger increase in the power availableto the turbine.

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Chapter 6

System Discription

6.1 System Architecture

Figure 6.1: Architecture of smart home energy management (HEMS) considering both energyconsumption and generation

Fig. 6.1 shows the schematic overview of the proposed smart HEMS. The smart

home consists of two parts: energy consumption and energy generation. The energy con-sumption in home is caused mainly by home appliances and lights. Outlets and lights areequipped with an energy measurement and communication unit (EMCU). The communi-cation capability is based on ZigBee, which is well known as a low power communicationmethod. The EMCU measures the energy consumption of home appliances and the lights.The EMCU in outlets and lights reports the measured values to the home server periodicallythrough ZigBee. The home server acquires and stores the energy information of home appli-ances and lights. The home server has the mapping information about which home appliance

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is connected to which outlet and about the location of lights. It then analyzes the energy andpower usages of home appliances and lights continuously. Users can figure out the energyusage status of home appliances and lights and find out which one is unnecessarily turnedon. The outlets and lights in home can be controlled for energy saving either automaticallyby the home server or manually by the users. Users can also access the information of home

energy usage information through a smart mobile device both locally and remotely.The energy generation part consists of a solar power generator and a wind power one,

which are two of the most popular RES. Solar panels on the roof are connected to theinverter, which converts dc power to ac one. Each solar panel is equipped with a PLCmodem to monitor the status of all solar panels for maximum power generation. The PLC isconsidered as a retrofit technology because it needs no additional communication lines. TheRenewable energy gateway (REG) gathers all the status information from the solar panelsbased on PLC and from the inverter through a serial communication. TheREG monitorsthe performance and status of all solar panels in real time. The status information of eachsolar panel enables users to maintain the performance of solar power generator. The REGalso gathers the wind power status from the wind inverter. The home server aggregates allthe power generation information and utilizes it for home energy management.

From the information of the energy consumption and the energy generation, the homeserver can manage and control home energy use according to the circumstances in real time.It estimates the renewable energy generation based on the weather information from theweather forecasting web service, which provides solar radiation, cloud amount, wind speed,and so on. The home server provides users with various aspects of analysis and helps themoptimize home energy use manually or automatically. Moreover, the energy managementserver gathers and stores the energy information of client homes, and it provides the energyportal service and helps clients compare the energy information of them with that of others

6.2 Home Server

The home server manages the EMCUs installed in outlets and lights through a ZigBeeAP. The home server monitors and controls the EMCUs through the node control block. Thedevice table manages both home appliances and lights connected to the EMCUs. The homeserver identifies home appliances and lights using this table. The energy consumption data ofhome appliances and lights are stored in the information database. The aggregated data arecontinuously accumulated over time. The energy consumption manager (ECM) analyzes theaggregated data over time, day, week, and month. It creates energy consumption informationsuch as: energy use patterns of homeappliance and lights; total energy use pattern of the

whole home.The home server figures out the energy consumptioninformation of a home usingthis energy consumption manager.

The REG transfers the status data of solar panels, a solar inverter, and a wind inverter tothe home server. The transferred data describe the performance of each solar panel, the solarpower system, and the wind power system. The data aggregator gathers the transferred dataand stores them in the information database. The home server uses weather data and storesthem in the information database. The weather data is used to generate the correspondencebetween energy generation and weather. The energy generation manager (EGM) analyzes

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Figure 6.2: Function blocks of a home server

the renewable energy generation and draws patterns over weather. Solar energy generationrelates to the solar radiation; wind energy generation relates to the wind speed. The EGMcan estimate renewable energy generation based on the weather forecast.

Based on the estimated energy generation, the home server modifies the home devicesschedule so that the energy cost is reduces. For example, in the low renewable energygeneration time and in high price time, the operation of several home devices can be movedto other times when the price is low. The home server decides which operation is movedbased on the priority of the operation.

The home user interface (UI) provides a variety of contents about home energy infor-mation to home users. The UI shows the energy consumption and generation informationover time. Users can browse and check the energy usage of each home appliance and each

light; they can also figure out how much energy is being generated and how much cost isbeing saved. The web service enables smart devices to access the home server and searchthe home energy information. Users can browse the home energy information through smartdevices anytime and anywhere through Internet. The home server provides the contents tosmart devices on demand. The smart devices can directly access the information using smartdevice applications. The home server transfers the home energy information to the REMSthat manages numerous client homes.

6.3 Energy Management and Communication Unit (EMCU

In the energy consumption part, the EMCU is a key component; it is composedof measurement and communication blocks. The measurement block measures the power,energy, and power factor of plugged home appliances. It uses an energy metering IC formeasuring them. The metering IC measures the voltage 9-+8and current in a sample period;it multiplies them; it integrates them continuously. The power and energy is calculated withthis process. The power factor is measure based the phase difference between voltage andcurrent. The measurement block stores only the accumulated energy data at a memory;it calculates the power and power factor on demand in real time. The measurement block

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includes the power control block that supplies or blocks the electricity to connected homeappliances.

The communication block supports data transfer between the EMCU and the homeserver. It adopts ZigBee and IEEE 802.15.4 wireless personal area network (WPAN) ascommunication methods. It transfers not only the measured energy, power, and power

factor but also the voltage and current. Fig. 3 shows the data transfer message that isloaded on the ZigBee payload. The MCU in the communication block controls the state ofthe power control block in response to the command from the home server.

Figure 6.3: Energy measurement and communication unit (EMCU) and protocol stack.

6.4 Renewable Energy Gateway and PLC Modem

In the energy generation part, the REG is a key component; it is connected to thePLC modems, the solar inverter, and the wind inverter. The PLC modems communicateswith TCP/IP protocol over PLC. They have their own IP address as an identifier. The con-nection manager controls connection with the REG. The sensing agent measures the voltageand current of a solar panel. The performance can be figured out from those sensed data.The PLC modem transfers the sensed data the REG. The REG has three communicationinterfaces: PLC for each solar panel, Ethernet for the home server, and an RS-485 for invert-ers. For typical network communication, TCP/IP protocol is used over PLC and Ethernet.The connection manager controls the connection with each PLC modem to aggregate thestatus data. Solar and wind inverters are connected through the RS-485 interface. The data

aggregator sends a data request message to each PLC modem and inverters; it receives thestatus data. The data sender transfers the aggregated data to the home server periodically.

6.5 Remote Energy Management Server (REMS)

Individual homes can subscribe the energy portal service that is provided by the REMS.The home server in each home transfers the home energy information to the REMS. The

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Figure 6.4: Architecture of a renewable energy gateway (REG) and a PLC modem.

client manager maintains the connection to the home server of subscribers. The REMS ag-gregates the detailed energy information from the client home server that provides the energy

use of home appliances and lights. The energy generation information is also transferred.All aggregated information is stored in the information database. The REMS calculatesthe average, maximum, minimum energy usage regarding homes and home appliances. Thecalculated information shows the standard energy usage pattern. It motivates subscribers tocompare their energy usage with that of others and to reduce home energy use. The energyportal service provides numerous subscribers with the statistical energy consumption andgeneration.

Figure 6.5: Remote energy management server (REMS) connected to the home servers of

subscr

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Chapter 7

Application

1. Energy cost can be reduced

2. Increase the power generation

3. Energy Monitoring

4. Know the cost of energy usage

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Chapter 8

Conclusion

The smart home energy management system is works well on real time. The systemcan be fully controlled by controller. Power consumption details are successfully uploadedinto the web server continuously. Solar power and wind energy are enough for production

of power to supply the home appliances. The implementation cost of the system is low andthis System is also reducing the cost of the power. During peak hour the heavy load homeappliances kept off to maintain the energy management and save the energy for nature andupcoming future generations. The benefits are we can not only have the power but also havethe knowledge of consumption.

8.1 Future Scope

Ensure reliable power supply

Encourage energy conservation and Emission reduction

Enhance the use of green energy

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Bibliography

1. Hayato Yamauchi, Kosuke Uchida, and Tomonobu Senjyu, Advanced Smart Home, inProc. IEEE International Conference on Harmonics and Quality of Power, Hong Kong,China, pp. 130 to 135, Jun. 2012

2. Young-Sung Son and Kyeong-Deok Moon, Home energy management system based onpower line communication, IEEE Trans. Consumer Electron., vol. 56, no. 3, pp. 1380to 1386, Aug. 2010

3. Jinsoo Han, Chang-Sic Choi, Wan-Ki Park, and Ilwoo Lee, Green home energy man-agement system through comparison of energy usage between the same kinds of homeappliances, in Proc. IEEE International Symposium on Consumer Electronics, Singa-pore, pp. 1to4, Jun. 2011.

4. Alphy John, I.Bildass Santhosam, Home Energy Management System Based OnZigbee, International Journal of Inventive Engineering and Sciences (IJIES) ISSN:23199598, Volume-2, Issue-4, March 2014 13.

5. Archana.S.Kokatanur1, Susham.K.Rao2 , Intelligent Home Energy Management Sys-tem Including Renewable Energy Based On Micazs Ijret, International Journal Of Re-search In Engineering And Technology ,Volume: 04 Issue: 04 Apr-2015, AvailableHttp://Www.Ijret.Org 842

Energy saving using zigbee

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