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Inventing an Energy Internet Concepts, Architectures and Protocols for
Smart Energy Utilization
Lefteri H. TsoukalasPurdue University
Fermi National Accelerator Laboratory Colloquium, April 29, 2009
Research Sponsored by Grants from EPRI/DOD, NSF, DOD, DOE
Consortium for the Intelligent Management of the Electric Power Grid (CIMEG)Purdue University, The University of Tennessee, Fisk University, Exelon, TVA, ANL
http://helios.ecn.purdue.edu/~cimeg
Outline
• Global Energy Realities
• Conservation
• Smart Energy
• Energy Internet
• Examples/Applications
• Summary
Global Energy Realities
• World demand for energy: approximately 210 million barrels of oil equivalent (boe) per day (7.5 boe ~ 1 mtoe - metric ton of oil equivalent).
• World oil demand: ~ 85 million barrels of oil per day (MM bpd)
• Aggregate world supply: ~85+ million barrels of oil per day (MM bpd)
• International markets allocate resources by price– Need ~5% excess capacity for a stable market– Markets have difficulties directing capital towards
infrastructural investments– Are we witnessing the beginning of a series of oil-
induced market crises?
Oil Consumption Per Capita
USA: ~25 barrels/year per capita
Japan/S. Korea: ~15 barrels/year per capita
China (2003): ~1.7 barrels/year per capita
India (2003): ~0.7 barrels/year per capita
Global Energy Growth
• Nearly 6.6 billion people with modern needs• Growth in energy demand still has significant
margins for growth– 12% of the world uses 54% of all energy– 33% of the world still has no access to modern energy– The other 45% uses 1/4 of the energy consumed by the
remaining 12% • Energy use by world’s richest 12%
– U.S.: 65 boe energy per person– Japan: 32 boe energy per person– U.K.: 30 boe energy per person– Germany: 32 boe energy per person
Peak (Long Plateau) in Global Oil Production?
Peak 2005(?) 85 mm bpd
By 2020: 50 mm bpd
Bakhtiari, S. A-M. World Oil Production Capacity Model Suggests Output Peak by 2006-07 , Oil and Gas Journal (OGJ), May 2004
~70% of Remaining Reserves
EnergyCrisis
EnergyCrisis Climate
Change
ClimateChange
Future: Utopia – Dystopia?
Resource Constraints
Resource Constraints
FinancialCrisis
FinancialCrisis
First: Do More with Less
• Conservation may be our greatest new energy discovery in the near future
• Smart energy can facilitate further convergence of IT, power, and, transportation infrastructures
• Smart energy can facilitate integrated utilization of new energy carriers – H2, Alcohols, Biofuels
• Can harvest energy usually wasted• Ambient energy MEMS
Electric Power Grid
• Secure and reliable energy delivery becomes a pressing challenge– Increasing demands with higher quality of service– Declining resources
• The North American electric power grid is operating under narrower safety margins– More potential for blackouts/brownouts– Efficient and effective management strategy needed
• Current energy delivery infrastructure is a super complex system (more evolved than designed)– Lack of accurate and manageable models– Unpredictable and unstable dynamics
• Can we build an inherently stable energy network?
US Electric GridUS Electric Grid• Evolved, not-designed• Developed in the first half of the 20th century without a clear
awareness and analysis of the system-wide implications of its evolution
Energy + Intelligent Systems
• Smart Energy = Energy + Intelligent Systems• Smart energy extends throughout the electricity
value chain– Smart Generation– Smart Grid– Smart Loads (End Use)
Smart Energy Distribution Management Systems
• Advanced Metering Infrastructure
• Supervisory Control and Data Acquisition (SCADA)
• Capacitor Bank Control
Source: HP’s, Smart Energy Distribution Management Systems, 2005
HP’s Utility Integration Hub for real-time service integration
Singapore:Smart Energy Vending
Smart Grids
• Smart grids is an advanced concept– Detect and correct incipient problems at avery early stage– Receive and respond to a broader range of information– Possess rapid recovery capability– Adapt to changes and reconfiguring accordingly– Build-in reliability and security from design– Provide operators advanced visualization aids
• Most of these features can be found in the Information Internet– The Internet is also a super complex system– It is remarkably stable
• Can we find an Internet-type network for energy systems?
An Energy Internet
• Benefits of an Energy Internet– Reliability
• Self-configuration and self-healing– Flexibility and efficiency
• Customers can choose the service package that fits their budget and preferences
• Service providers can create more profits through real-time interactions with customers
• Marketers or brokers can collect more information to plan more user-oriented marketing strategies
• The regulation agency can operate to its maximal capacity by focusing effectively on regulating issues
– Transparency• All energy users are stakeholders in an Energy Internet
Storage and Buffer
Buffered Network
Energy Storage• Similar protocols could be developed for the power
grid in order to – Resolve conflicts due to the competition over
resources (peak demand), and– Identify and contain problems locally
IF electricity can be stored in the grid(!)
• Unfortunately, large scale storage of electricity is technologically and economically not feasible
• Solution: a virtual buffer– Electricity can be virtually stored if enough information
is gathered and utilized
Virtual Buffer: Concepts• Assume predictability of demand • Based on demand forecast, the desired amount of electricity is ordered (by an intelligent
agent on behalf of the customer) ahead of time• The supplier receives orders and accepts them only if all constraints are met. Otherwise,
new (higher) price may be issued to discourage customers (devices) from consuming too much electricity
• Price elasticity is used by the supplier to determine the amount of adjustment on price• Once the order is accepted, from a customer's point of view, electricity has been virtually
generated and stored
Time
Period when electricity is virtually stored
Virtual Buffer: Implementation• Information can be used to
achieve the virtual storage of energy
• Two keys for implementation– know electricity demand for
individual customers in advance
– Regulate demand dynamically• Hardware
– An intelligent meter for every customer to handle the planning and ordering automatically
• Algorithms– Demand forecast– Dynamical regulation via price
elasticity
Virtual buffer
Unbuffered Network
An Intelligent
Meter
Example LAG
Customer ID’s
Long- and Short-term Elasticity• Long-term Elasticity
– Average elasticity in within a long period (moths, years)– Usually is an overall index including a large number of
customers– Good for long-term strategic planning– More reliable to estimate
• Short-term Elasticity– Instant elasticity within a very short period (e.g., minutes,
hours)– Can be a local index for a particular customer– Critical for control of the power flow– Difficult to estimate
Managing Short-term Elasticity
• Short-term price elasticity characterizes a particular customer’s nearly instantaneous responsiveness to the change of price
• Short-term elasticity can be estimated from– Historical price-demand data – Psychological models of customer energy behaviors
• The use of intelligent meters is important for– Increasing short-term elasticity => more effective for control– Regulating customers’ behavior => more reliable for prediction
Example Approach
Grid is viewed as polycentric and multilayered system
Customer-driven Grid segmented by
groups of customers (LAGs)
Accurate predictions of nodal demand drive the system
Optimal dispatch of units (storage)
Plug and play tool: TELOS
Transmission
Distribution
Sub-transmission
Residential Customers
Medium-Large Customer
Large CustomersVery Large Customers
To other LAGsTo other LAGs
Customer-SideAgent Space
Generators
Generators
Local Area Grid - LAG
– Defined as a set of power customers
– Power system divided into Local Area Grids each with anticipatory strategies for• Demand-side
management
• Dispatching small units
• Energy storage
• Good neighborly relations
Central Dispatch
Small Generator
Sheddable Load
Data Network
Local Grid 1
Local Grid
Local Grid 2Local Grid 3
TELOS Design Requirements
• TELOS = Transmission-distribution Entities with Learning and On-line Self-healing
• Local Area Grid (LAG)
• Customer-centric
• System Model
• Power System Calculations
• User Interface
• Automated Execution
Examples of Customers in TELOS
0 20 40 60 80 100 1200.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 20 40 60 80 100 120350
400
450
500
550
600
Large Commercial /Industrial (LCI) Customer Hourly Demand (KW-h) for a week
Residential (RSL) Customer Hourly Demand (KW-h) for a week
KWh
KWh
Hourly data starting at 00:00 Monday
Intelligent Power Meter
Pow
er
Info
Prediction Agent
Historical data
Decision Module
Effectors
Database
Actions
LAG Manager
TELOS Simulation
Demand Forecast in TELOS
1/25/2002 2/25 3/25 4/25 5/25/2002
2
4
6
8
10
12
14
Time (30 min interval)
MW
actualprediction
Argonne National Laboratory (ANL)
Dynamic Scheduling via Elasticity
OrderingPowerFlow
PowerPrediction
SecurityCheck
ElasticityModel
PowerFlow
CapacityCheck Scheduling
ElasticityModel
BackupPower
Generation Agent
Customer withIntelligent Meter
Transmission/DistributionAgent
Pric
ing
Info
N
Y
N
Y
N Y
Convergence of IT and Power
• Technological advancements– More information/data is available
• Transmission and delivery system monitoring: SCADA, ….
• Smart grid/smart meter
– More analytical tools are available.• Economics models
• Power system analysis tools
• Can we build around current technologies a more reliable and efficient infrastructure?– Utilize complex systems theories (multi-agents)– Software (information infrastructure) upgrade
Open- vs Closed-Loop System
Generationg(t)
Consumptionc(t)
Storages(t)
Generationg(t+t0)
Consumptionc(t+t0)
Delivery System
Pricing p()
Order f()
Open-Loop System
Closed-Loop System w/ Anticipation
Equilibrium is reached at future state!
Energy Internet: Anticipation and Pricing
Without anticipation
Power Generation Level
0 20 40 60 80 100350
400
450
500
550
600MW
120Hours
0 20 40 60 80 100350
400
450
500
550
600MW
120Hours
Dynamic Generation Consumption
0 20 40 60 80 100350
400
450
500
550
600MW
120Hours
Dynamic Generation Consumption
With anticipation
With anticipation and pricing
0 2 4 6 8 10 12 14 16 18 20 22 2411,000
12,000
13,000
14,000
15,000
16,000
17,000
50
60
70
80
90
100
110
120
130
Peak Demand and Pricing
Source: NE ISO
Prof. G. Gross, UIUC
pri
ce (
$/M
Wh
)
time of day
dem
and
(M
W)
average demand
Research Issues• Multi-agent based methodology• Asynchronous and autonomous system• Demand Side: Smart Meters
– Anticipation– Programmable energy management– Communication and negotiation– Plug-ins
• Supply Side– (distributed) Power system analysis – (distributed) Pricing models– Renewables (solar, PV, geothermal…)– Vehicle-to-grid
Outstanding Issues
• Feasibility– Can system reach equilibrium?
• Efficiency– How much electricity can be conserved (negawatts)?
• Stability– How does the system react in unexpected events?
• Scalability– What if the size of the system increases?
• Cost– How much investment is needed for upgrading current
infrastructure and evolving towards energy internet?
Summary• An Internet-like energy network, an Energy Internet,
representing the smart convergence of Power and IT, is a technically plausible next step
• Intelligent Systems can provide virtual energy storage (via anticipation)
• The Energy Internet may positively shape a sustainable future through more transparent energy relations
• All sources of primary energy will be needed to produce the most easily available energy we have, grid electricity
• Nuclear power has a special role as an important source of emissions-free electricity with some sustainability features
• Important nuclear physics advancements needed to enable global standards for future nuclear fuel cycles
Extra Slides
Load Identification and Wavelets
– Different types of load show a characteristic behavior on the change of wavelet coefficients with respect to scale
– The type of load is possible to be identified with a neural-wavelet approach
Wavelet Decomposition
20 40 60 80 100 120 140 160
-101
Ori
gin
al
20 40 60 80 100 120 140 160
-1-0.5
00.5
s
20 40 60 80 100 120 140 160-0.5
0
0.5
d5
20 40 60 80 100 120 140 160
-0.5
0
0.5
d4
20 40 60 80 100 120 140 160-0.5
0
0.5
d3
20 40 60 80 100 120 140 160-0.5
0
0.5
d2
20 40 60 80 100 120 140 160
-0.2
0
0.2
d1
20 40 60 80 100 120 140 160
0
2
4
Ori
gin
al
20 40 60 80 100 120 140 160
-0.20
0.20.40.6
s
20 40 60 80 100 120 140 160
-0.50
0.5
d5
20 40 60 80 100 120 140 160
-0.50
0.5
d4
20 40 60 80 100 120 140 160-1
0
1
d3
20 40 60 80 100 120 140 160
-1
0
1
d2
20 40 60 80 100 120 140 160
-101
d1
LCI RLS
Load Identification
LCI RLS
0 50 100 150 200 250 300 350-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
0 50 100 150 200 250 300 350-0.5
0
0.5
1
Structure of LAG
LAGMANAGER
Producer #1
Producer #2
Producer #N
Consumer #1
Consumer #2
Consumer #M
To neighboring LAG
LAG Manager
• Collects current demand and supply data• Checks for grid stability based on predictions
of individual customer demand and available pathways
• Makes decisions on when to dispatch local units and/or manage load based on demand/supply and contracts between customers and producers/providers
• Sends decisions to individual agents
Interconnecting LAGs
• Reliable network connections with adequate redundancy
• Each LAG connecting to at least two neighboring LAGs
• Neighboring LAG Manager should be able to take over in case of local fault
LAG Agent Hierarchy
Substation
Transformers
Feeders
Customers
Agent Functionalities
• Customer Agent: contains a neurofuzzy predictor to predict future demand
• Feeder Agent: sums up predicted demands of all customers connected to the feeder, performs internal overload check
• Transformer Agent: sums up predictions of all the feeders
TELOS Implementation
• Distribution Agency: Propagates Agents Through the Network
• Intelligent Meters Contract for Power in a Central Database
Intelligent Power MeterPow
er
Valu
e
Prediction Agent
Historical data
Decision Module
Effectors
Database
Actions
LAG Manager
Anticipatory Control of Small Units
The objective at time k is to find an open loop set of constrained control actions u(k) to drive the plant outputs y(k) along a desired trajectory with anticipated disturbances v(k).
Controller Plant
Anticipated Disturbances
Current System Trajectory Estimation
Noise
ky * ky
k
kukv
Load Schedule
Forecasting
Nk
k
k
N
u
u
u
U
1
Logging Optimal Control Patterns• Iterate to find the optimal control response
• Log the system trajectory at time 0
• Log the predicted error at time 1
• Log the optimized control action at time 0
Control Action
Logging Optimal Control Patterns• Train a neural
network to learn the optimal, tuned, anticipatory control response
• Example: If the error will be negative and the current system trajectory is level, then decrease fuel flow rate.
Control Action
Anticipatory Control of Small Units
Smoothness of Control - Time Rate of Change of Fuel Flow
Conventional Control
Anticipatory Control
• 1/25th of Control Effort• Reliability and Maintenance Benefits• Energy Savings