Embedded Systems for Smart Appliances and Energy Management

158 Pages·2013·4.76 MB·English

by  Holger Hermanns

Embedded Systems
SeriesEditors
NikilD.Dutt,DepartmentofComputerScience,ZotCode3435,DonaldBren
SchoolofInformationandComputerSciences,UniversityofCalifornia,Irvine,
CA92697-3435,USA
GrantMartin,TensilicaInc.,3255-6ScottBlvd.,SantaClara,CA95054,USA
PeterMarwedel,TUDortmund,Informatik12,Otto-Hahn-Str.16,44227
Dortmund,Germany
For furthervolumes:
http://www.springer.com/series/8563

Christoph Grimm (cid:129) Peter Neumann
Stefan Mahlknecht
Editors
Embedded Systems
for Smart Appliances
and Energy Management
Editors
ChristophGrimm PeterNeumann
TUKaiserslautern edacentrumGmbH
Kaiserslautern,Germany Hannover,Germany
StefanMahlknecht
InstitutfurComputertechnik
TUVienna,Wien,Austria
ISSN2193-0155 ISSN2193-0163(electronic)
ISBN978-1-4419-8794-5 ISBN978-1-4419-8795-2(eBook)
DOI10.1007/978-1-4419-8795-2
SpringerNewYorkHeidelbergDordrechtLondon
LibraryofCongressControlNumber:2012945006
#SpringerScience+BusinessMediaNewYork2013
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Can Embedded Systems Reduce
Carbon Dioxide Emissions?
The short answer to the question is “yes!” – provided that we can satisfy a key
requirement:wemustachievethewidespreaddeploymentofintelligent,low-cost,
distributedcommunicationsthatoperatedowntothelevelofindividualhousehold
and office appliances. To understand why we need such a communications infra-
structure,wemustfirstremindourselvesoftheoverallpowergenerationchallenge
anditscontext.
Reducing carbon dioxide (CO ) emissions is a global challenge. Clearly, low-
2
carbon/no-carbon renewable energy sources such as wind turbines and
photovoltaics will play an important role in any future CO reduction strategy.
2
However, we operate under one non-negotiable constraint: the stability of the
distribution grid is of primary importance. Consequently, the overall availability
of electrical energy must match the overall consumption at all times. However,
renewable energy production is volatile, so we must find a means to prevent this
volatility from destabilising the grid. We must address such grid stability issues
robustly if we are to avoid catastrophic failures such as the 2003 blackout in the
NortheasternandMidwesternUnitedStatesandinOntario,Canada[1].
The solution to the problem of renewable energy volatility is intelligent man-
agement of both energy generation and its consumption, simultaneously. And we
must ensure that energy consumption matches energy generation – the reverse of
the status quo in industrialized countries today. This approach is already state-of-
the-art among large-scale energy consumers such as manufacturing industry. In
contrast,smallbuildingsandneighbourhoodshaveyettoadoptsuchanapproach–
andyettheyconsumeapproximately30%ofoverallenergyoutputandcontribute
approximately20%tooverallCO emissions[2].
2
Until now, energy generation has very largely been centralized. However,
renewable energy sources are becoming an increasingly important part of the
overall energy generation mix. Consequently, the generation infrastructure will
very rapidly evolve into a decentralized approach, with a huge number of small-
scale generation facilities feeding local clusters of consumption facilities. The
resulting increase in generation volatility clearly poses a stability risk to the grid.
Howdowesolvethisproblem?
v
vi CanEmbeddedSystemsReduceCarbonDioxideEmissions?
Information and Communication Technologies (ICT) are critical enabling
mechanismstohandlethesechallenges.Usingsuchtechnologiestolinktheenergy
generation facility with monitors/controllers embedded both in buildings and in
individualhouseholdandofficeappliancesenablesthegenerationfacilitytoknow
themagnitudeanddistributionofenergyconsumptioninitslocalcluster,minute-
by-minute. Without this real-time communication between energy generation,
energy delivery and energy consumption entities, intelligent energy management
isnotpossible–andtheresultwouldbeenergygridinstability,resultinginfrequent
blackouts.
1 Energy Management: A Multi-Disciplinary Challenge
The intelligent management of both energy supply and energy demand in an
(at least, partially) decentralized system that also exploits (at least, partially)
renewable energy sources, is not a trivial task. Readers will apprehend from this
book that the design of the embedded systems that manage, monitor, and control
such energy-consuming entities and of the communications that link them to the
energygenerationpointisamulti-disciplinarychallenge.Itrequirestheexpertiseof
scientists, engineers and social scientists to devise the economic/business models
thatunderpinthefinancialviabilityofthetaskandtodesigntheembeddedsystem
implementations. The solution marries economics with power engineering, com-
puterscience,wirelesscommunications,microelectronics,andothers.
The energy generation industry is the single, largest industry in the world.
Energy is produced in a centralized manner and distributed unidirectionally to its
endusers.However,largecentralizedpowerplantsarehighlyinvestment-intensive.
Experience in securing the initial investment for large offshore wind farms in the
NorthSeademonstrateshowdifficultitis–justasdifficult(orevenmoreso)asfor
conventional fossil fuel plants. In contrast, decentralized, small-scale renewable
energygenerationisnotonlyconsiderablylessinvestment-intensive,itisalsocost-
effective, highly scalable, and offers customer participation. Energy users can
participate in new, regional, decentralized energy markets – leveraging
photovoltaics,wind,biofuels,andsoon–inwhichallstakeholdersaremotivated
togenerateanduseenergyinacost-effectivemanner.
The energy customer is buying not only energy, but also an energy supply
service,andneedstheenergytobethereinrealtime,notnextweek.WithDemand
Site Management (DSM) approaches that match demand to available supply,
however, the end customer has to accept constraints in the way he or she uses
local energy-consuming appliances. It is a major requirement that the constraints
mustnotsignificantlyreducecustomercomfortorconvenience,otherwisewewill
not achieve widespread user acceptance. On the other hand, some reduction in
comfortorconveniencemightbeacceptableif,forexample,customersseethatthe
constraints reduce costs or prevent price increases or, in emergency cases, assure
gridstability.Energymanagementmethodsalsoplayaroleintheefficiencyofthe
CanEmbeddedSystemsReduceCarbonDioxideEmissions? vii
energymarket.Energymanagementenablessupplierstoadjustpricesaccordingto
energy supply and demand – provided that maximisation of profit has no adverse
effectsongridstability.
Classicalpowerengineeringdealswiththefamiliar,well-establishedinfrastruc-
turethatgenerateselectricalenergyfromconventionalpowerplants,togetherwith
alimitedamountofenergyfromrenewableenergysources,andthendeliversitto
householdsandindustry.Astheproportionoftotalenergyderivedfromrenewable
sourcesincreases,theintelligentmanagementofthepowergridsofthefuturewill
standorfallonitsabilitytotransferinformationbidirectionallybetweendifferent
points of generation and use; on its analysis of the collected data; and on its
identificationandinitiationofrequiredactionsandresponsesbasedontheanalysis.
Building-levelsolutionswillalsoinvolveenergystorage(invariousenergyforms),
aswellasthelocalmanagementofconsumption.
To support the new supply/demand matching paradigm, Demand Response
Management (DRM) tries to adapt consumption to the availability of energy.
Given a new structure with a massive enhancement of the grid by manageable
small-scale consumption and generation entities (“prosumer”), two important
questionsarise:
(cid:129) How do we connect the “last-mile” of the grid to the grid’s management
information network? Do we really have to do it, or can we avoid the massive
investmentrequiredbyexploitingaone-waycommunicationanalysis?
(cid:129) HowdoweguaranteefairenergydistributionwhenDRMshiftsloadsbetween
energysources,and/orwhenitreduceseitherlocalconsumptionorgeneration?
Asalreadymentioned,thetransferofdata,itsanalysisandtheresponsesarethe
basisforintelligentenergymanagement.Sincesensitivedatawillbecapturedand
transmitted, Information Security is of major concern. People simply don’t want
grid operators to track them in their homes or hackers to sabotage their energy
supply.Sodatasecuritymustbeensuredatalltimes–andnotonlywhenadevice
orasystemisinoperation;itmustalsocoverthedevice’sintegrationintoasecure
network–thecommissioningphase–whenanewdeviceorsystemisidentifiedand
authorizedbysecuremechanisms.
Afurtherimportant issueiscost.Solutionsavailabletodaycostintherangeof
severalhundredU.S.dollarspermanaged“smartappliance”,whichistwoordersof
magnitude greater than is economically feasible for widespread deployment in
small buildings and neighborhoods. To reduce costs to consumer price levels, we
need microelectronic platforms. The European research project SmartCoDe [3]
estimates that the requisite, highly-integrated microelectronic components can be
madeavailableatapricebelowfourdollarspermanageddevicewhenproducedin
largevolumes.
However,costisnottheonlyissue.Sincesuchadevicewillbeintegratedintoa
hugenumberofsmallappliances,Low-Powerisalsoamust.Thedesignofalow-
powerSysteminPackage(SiP)orSystemonChip(SoC)requirestheintegrationof
several different technologies. Significant expertise is needed in areas such as
viii CanEmbeddedSystemsReduceCarbonDioxideEmissions?
sensor/actor technologies, analogue/mixed-signal development, digital design,
softwaredevelopmentandtheSiP/SoC’simplementationinembeddedsystems.
Theabovelistisfarfromcomplete–thereareevenmoreissuestobedealtwith.
Ourintentionistoshowthattoday’schallengescannolongerbesolvedbyfocusing
on a single issue. To address the issues every one of us has to understand the big
pictureanditsimplications.Thefutureisinter-disciplinary.
2 Overview of the Book Chapters
The topic of the book is embedded systems for smart appliances. Embedded
systems usually stand for the integration of a (microelectronic) system and its
softwareintoalarger,oftenautonomous,systemthatoftenmonitorsand/orcontrols
equipmentwithouttheneedformanualintervention.Examplesofcommonembed-
ded systems are the anti-lock braking system (ABS) in a car and the “fire-and-
forget” electronic thermostat in a house. For the purpose of the book, we like to
think of the term embedded also in terms of integrating the appliance into its
intendeduse-casewithallimplicationsconsidered.Thebookthereforefollowsan
unconventional path for an academic technical publication: with the first two
chapters,we set the stage before we dive into “hard core” embedded systems and
microelectronics.
InChap.1,DemandResponseManagementforDependableSystems,weelabo-
rateonthechallengesarisingfromtheintegrationofrenewableenergysourcesinto
thegrid,andtherequirementtointelligentlymanagesmall-scaleelectricalenergy
consumptioninthefuture.
InChap.2,IntelligentSmall-ScaleDecentralizedEnergySystems,wearguethat
we must redesign the current energy grid structure from a mainly-centralized
network to a fully-exploited decentralized network in order to cope with the shift
from fossil fuels to renewable energy sources. Small-scale decentralized systems
not only contribute to the affordability of energy, but also to future grid stability,
limitinggridblackoutstosmallregions.
InChap.3,ModelBasedDesignofSmartAppliances,wediscussmethodsand
algorithmstocontrolthedemandforelectricalenergydependingontheavailability
ofpowerinthegrid,andhowtherequirementscanbedevelopedthroughmodeling
and simulation. The focus here is on small buildings and neighborhoods, and we
willalsointroduceanewequipmentcategory,EnergyusingProducts(EuP).
In Chap. 4, Wireless Standards for Building Automation, we discuss wireless
technologies,whicharethemostpromisingoptionforintegratingenergymanage-
mentintoexistingbuildings,whereonlyalimiteddegreeofretrofittingispossible.
Ofcourse,newbuildingscanbedesignedfrombasementupwithintegratedenergy
management,buttheseconstituteasmallpercentageofallbuildingsthatmustbeso
equipped.
CanEmbeddedSystemsReduceCarbonDioxideEmissions? ix
In Chap. 5, Smart Embedded Appliances Networks – Security Considerations,
we analyze threats, processes and context. We then introduce cryptographic
conceptsasneededinbuildingautomation.
In Chap. 6, Embedded and Integrated Platforms for Energy Management, we
suggestatop-levelhardwarearchitectureforaddingenergymanagementfunction-
alitytoenergy-usingproductsthatalsofulfillsthestrictrequirementsforsecurity,
low power, and low cost. The suggestion takes a platform-based approach, which
eases and speeds the design of microelectronic components, tailored to meet the
requirementsoftheirtargetusecase(s).
InChap.7,PowerSuppliesforLowPowerApplications,wegiveacomprehen-
siveintroductiontothedesignoflow-powerandlow-costpowersupplyunitswith
highefficiency,includingtheneedforultra-lowpowerstandby.
In the last chapter, Chap. 8, Design of Energy Measurement Units for Smart
Metering,wediscussthetopology,architectureandcircuitdesignissuesrelevantto
highly-integratedsmartmetering,acriticalfeatureofthisbook’sproposedmicro-
electroniccomponent.
3 Thanks
The majority of results presented in this book have been supported by research,
partially funded by the European Commission seventh framework program. We
wouldliketoexpressourthanksandappreciationthatmeasuressuchastheseexist
andhelpusalltodotherightthing.
PeterNeumannandChristophGrimm,HannoverandVienna,April2012
1. Final Report on the August 14th Blackout in the United States and Canada,
U.S.-CanadaPowerSystemOutageTaskForce,https://reports.energy.gov/
2. Worldwide Trends in Energy Use and Efficiency, Key Insights from IEA
IndicatorAnalysis,InternationalEnergyAgency,http://www.iea.org
3. www.fp7-smartcode.eu
Hannover,Germany PeterNeumann
Kaiserslautern,Germany ChristophGrimm