Sioshansi F.P. Smart Grid: Integrating Renewable, Distributed & Efficient Energy

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Figure 11.3

The data model tracks relationships between a service delivery point and

various devices, grid connections, and premises data.

Source: Chris King, MDM Implementation Course, October 2010

To assist in utilizing the data, the data model may also

support tracking of the electrical connectivity of devices. For

example, the database could track to which distribution

substation, feeder, and transformer a smart meter is

connected. This would assist in diagnosing the cause of an

outage reported by an alert from that meter, because the

utility would know which substation, feeder, and transformer

was involved.

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Device Provisioning

Provisioning in this context refers to establishing the secure

logical connection between a home and an account or another

device. Linking a new Bluetooth headset with your cell phone

is one example of provisioning. It is obviously important that

it links with your cell phone, and not someone else's.

In the smart grid, provisioning is important to link a newly

installed smart meter with the correct customer account and to

link an increasing number of in-home devices to the correct

smart meter. This way, for instance, the consumption from the

correct meter is displayed on the correct device, so neighbors

are not seeing each others’ consumption. The value of this

and similar applications is described in Chapter 15.

The IT environment challenges associated with device

provisioning can be significant. The utilities in Texas struck

an innovative approach, building on their existing Smart

Meter Texas platform. Energy service providers offer

customers programs that often include in-home devices.

Rather than duplicating the function, the central Smart Meter

Texas service manages all device provisioning between these

customer devices and the utility's smart meter.

Communications Maintenance

Successful smart grid communications require that the

devices, communications network, and software applications

are all working properly. When something fails,

communication stops or data become corrupted. Utilities need

IT systems that monitor the communications processes. Some

system needs to check whether communication is operating

successfully with each device on the network and whether the

expected data exchanges are happening. For example, most

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smart meter systems deliver data to the utility's meter data

management system at least once a day, during some

expected time window. A software application needs to check

for this delivery, meter by meter, and report which meters

have failed so send data. This is typically done in the meter

data management system but could also be done by the

head-end communications management software that runs the

smart meter network, the so-called advanced metering

infrastructure, or AMI, head-end.

The other challenge with smart grid communications is what

to do when communications fail. It is one thing to identify, as

described above, that a meter has not reported data as

expected. It is another thing to determine why the data were

not reported and how it can be fixed. The reason could be a

meter failure, a failure of the radio in the meter, a failure of

the network concentrator unit that normally receives the data

from the meter, a failure of the wide area network (WAN)

connection to the concentrator,

or other things such as a

power outage or temporary radio interference.

To clarify, the WAN is the communications link between the utility

office and communication nodes typically mounted on utility poles in

neighborhoods. From there, pole-top nodes communicate via radio

frequency or power line carrier to the meters in the areas, this being the

LAN. The meters then communicate via a separate radio or power line

carrier modem into the home or building to connect to smart devices;

this is the HAN.

Exception Management

Some IT system needs to identify the failure—also known as

an exception—diagnose possible solutions, and initiate a

resolution—all automatically—because manual processes are

cost prohibitive in a network of millions of devices.

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Exception handling is the bane of operations departments, and

automated processing is seen by utilities as a major smart grid

benefit.

Southern California Gas Company, Advanced Metering Infrastructure

Chapter II – Summary of AMI Business Case, Testimony Filed with the

California Public Utilities Commission, September 29, 2008.

The resolution is typically one of these three approaches:

• A retry of the communications, an automated repeat

request for the information. Such retries are part of the

basic operations of the AMI head-end software. However,

retries can be initiated by upstream systems as well, such as

the meter data management system or billing system.

• Simply waiting another day. Missing meter reads in a

daily file of smart meter reads are often resolved the next

day in the regular daily meter reading process. This

happens automatically in the operation of most AMI

technologies.

• Manual intervention. A work order is created by the

meter data management system, CIS, or work management

system—or manually—and a human being takes various

steps to diagnose and solve the problem.

Integration of Software Applications

Making the smart grid work requires different IT systems to

talk to one another reliably and efficiently. The AMI

head-end software needs to talk to the meter data

management system, which needs to talk to the billing

system. Linking all of these systems can be quite

complicated. When multiple systems are involved, and each is

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individually connected to others, the result is sometimes

called “spaghetti integration” as shown in Figure 11.4.

Figure 11.4

With the smart grid, multiple software applications must be connected with one

another to deliver the desired functionality; a common outcome is “spaghetti”

integration.

Source: Chris King, MDM Implementation Course, October 2010.

The challenge of application integration is increased by the

diversity of the systems. Some are new, others old. For

example, a brand-new AMI head-end may be connected to a

20-year-old legacy billing system. Moreover, technical

interfaces differ, ranging from modern, XML-based,

interfaces to traditional batch-based file exchanges. In

addition, timing requirements may vary substantially, with

outage management systems typically using real-time data

exchanges, while billing systems operate with nightly file

transfers.

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Essential Smart Grid Software Platform

During the implementation of a large-scale advanced or smart

metering project, the biggest risk is not related to the meters,

the communications, nor even the installation. The greatest

potential for getting less functionality than was bargained for

or spending more money is a poorly designed information

technology (IT) architecture. Getting it right is one of the key

steps in ensuring project success. To reiterate, while there

certainly are risks associated with investing in smart metering

equipment, there are even larger risks of not investing in an

integration platform to support the smart metering investment

and enable the desired functionality.

Utilities have two overarching goals in providing electricity:

maximizing reliability and minimizing costs. These should be

the same goals of the IT design for an advanced metering

infrastructure. Reliability means timely, complete data, as

well as seamless integration with billing, outage, field

maintenance, and other essential business systems. Reducing

costs means—well—spending less money, of course.

Smart Application Integration Platform

Smart grid functions can be implemented in one of three

ways: 1) in a purpose-built smart grid integration platform, 2)

in smart grid data communications software, or 3) in existing

utility core business systems. The most reliable, cost-effective

architecture is usually the first, as shown in Figure 11.5.

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Figure 11.5

An integration platform allows sharing of communications networks and data

by multiple utility application systems; it also supports multiple meter

communications technologies.

Chris King, MDM Implementation Course, October 2010.

Utilities have found the integration platform architecture to be

the most reliable and cost effective for several reasons:

• It centralizes all the smart meter data management

activities, linking, for example, data collection with data

management and the data warehouse. This results in fewer

personnel and less friction between business units than

might otherwise be experienced if these functions were

separated into different departments,

• It places all of the smart meter data activities in a platform

focused on meter or other endpoint data. It has reliable and

efficient operation of that platform as its sole mission.

• It effectively and safely manages the typical situation of

utilities using multiple networks and technologies, on the

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one hand, and multiple utility core business systems on the

other hand.

• It reduces maintenance costs for both the networks and

the utility business systems, because those systems can be

operated, maintained, and even replaced on an individual

basis without requiring major modifications to the other

interconnected systems.

Issues Associated with Other IT Architectures

One alternative is to implement the smart grid platform

functions in the head-end of the smart meter communications

system. The focus of that system is the operation of the

communications network, not managing meters or data. These

systems are optimized for network operation, a very different

function from data management. Such an approach makes it

much more difficult to integrate multiple communications

technologies, a required feature of every utility as technology

evolves more and more rapidly.

Another alternative is to implement the smart grid platform

functions by modifying core utility business systems. This is

expensive because these systems are complex and were built

to provide different functions, such as billing. This also adds

risk, because the modifications to the legacy systems must

happen in parallel with smart grid implementation. In some

cases this approach would drive modifications to systems that

are scheduled for replacement even before the smart grid or

smart meters are fully deployed. These parallel activities

mean the system can focus on neither its primary

function—say billing—nor the smart metering

implementation.

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Multiple Operating Companies/Multiple Utilities

The smart grid platform approach supports utilities with

multiple operating companies or jurisdictions where multiple

utilities and multiple communications networks are involved.

This would allow, for example, consistent business rules for

validating data to be applied across all operating companies.

If there are valid reasons for differences in the business rules,

it provides a central location to manage business rules. An

added benefit of the platform is that it also allows utilities to

work through merger-related consolidation of smart grid

communication networks into a single, common system for

use by the sister utility companies.

System Interfaces and Interoperability

Every time data are exchanged between one device and

another, or between one software system and another, the data

must pass through the interface between the devices or the

systems. This interface includes numerous layers. The

underlying layer is the physical communication: a wire, a

radio signal, or something else? Another key layer is the

communications protocol, the language the devices or

systems speak. A third important layer is the data structure.

Standards are used in each layer to enable numerous and

diverse devices and systems to work together.

The internet provides an illustration. The physical layer is

often a radio connection within the home to a router, then

over a cable wire to the cable company's data center, and from

there perhaps by microwave radio to the website host's data

center in another city. The communications protocol is IP,

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which stands for Internet Protocol. Web pages use HTML

(hypertext mark-up language) as the data structure for the

information presented in a browser.

For the smart grid, such standards are also needed for ultimate

interoperability of devices and systems. The scope of these

standards goes beyond that of this chapter, other than to note

that the Federal Energy Independence and Security Act of

2007 mandates the development of such standards and

adoption by the Federal Energy Regulatory Commission.

The National Institute of Standards and Technology (NIST)

has responsibility for coordinating the adoption of these

standards. Utilities desiring to maximize the value of the

smart grid IT infrastructure are embracing these standards

where applicable and feasible.

H.R. 6, Energy Independence and Security Act of 2007, Section 1305,

“Smart grid interoperability framework.”

The most important standards are those that apply to

interfaces where data are exchanged between one entity and

another. One example is sharing data between utilities and

third parties authorized by customers via the OpenADE

standard (“Automated Data Exchange”).

Another example

is sending data from the utility-owned meter to a

customer-owned HAN device via the OpenHAN standard.

These interfaces are shown in Figure 11.6.

OpenADE and OpenHAN are under development under the auspices of

the National Institute of Standards and Technology. Details are available

at NIST's website for smart grid: http://www nist.gov/smartgrid/.

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Sioshansi F.P. Smart Grid: Integrating Renewable, Distributed &amp; Efficient Energy

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Sioshansi F.P. Smart Grid: Integrating Renewable, Distributed & Efficient Energy