AT THE CONSUMER
“The interface between the Smart Grid and the customer domain is of special importance. It will be the most visible part of the Smart Grid to the consumer,” the NIST report says. As noted earlier, the conceptual reference model divides the interface to the customer domain into the meter and the ESI. That ESI is the gateway to the customer premises network.
The meter and the ESI measure and record electricity usage, communicating that data upstream to the service provider. They also handle all sorts of service provisioning and maintenance functions, such as troubleshooting and remote connection and disconnection of service. Most importantly, this is where pricing and demand response signaling occurs.
There are many “blue-sky” opportunities for design here. “New and innovative energy-related services, which we may not even imagine today, will be developed and may require additional data streams between the Smart Grid and the customer domain,” the NIST report says. “The diversity of communications technologies and standards used by devices in the customer domain presents a significant challenge to achieving interoperability. In addition, ensuring cyber security is a critical consideration.”
It’s helpful to understand the distinction between the meter and the ESI, which the report considers “a very important forward-looking aspect of the reference model.”
Beyond measuring, recording, and sending information about electricity usage, the meter must also measure the flow of power back into the grid from distributed generation or storage resources located at the customer’s premises.
There are a number of design issues associated with the meter’s ownership. Early experiences with smart meters in test markets in California demonstrate a need for meter manufacturers to work closely with their utility customers, so the people at the utility who deal first-hand with the public fully understand how the things work. An inability to answer an audience question like “Does the smart part of the meter get its power from your side of the meter or mine?” at a town-hall meeting really throws cold water on a beta-test.
Distrust arises because, unlike everything else at the customer’s premises, the meter belongs to the service provider, which may or may not be the same company as the electric utility.
Perhaps designing an ESI looks more appealing. If you’re designing an ESI, remember that it’s an information management gateway through which the customer interacts with energy service providers. ESI standards must allow for innovation in market structures and services. Its basic functions demand response signaling such as price/kWh information, but the possibilities for more advanced services are limitless.
One of the differences between residential environments and commercial/industrial environments is the level of sophistication and customer participation that can be assumed in configuring premises networks to achieve interoperability and security in Smart Grid communications.
Although many homes already have one or more data networks that interconnect computers or consumer electronic devices, this is not universally true. Even in homes that have data networks, consumers may not care to configure appliances to communicate over their home network. Anyone who is not a hard-core technophile would prefer to purchase, for example, a Smart Grid plug-and-play clothes dryer.
In a similar vein, many physical data communication interfaces—wireless and wired—are available for the home environment. It’s is a virtual Tower of Babel. Possibly the efforts of the Home Grid Forum’s G.hn group will show the way.
PRIVACY
Throughout the Smart Grid standards process, privacy is a serious concern. Smart meters are read often. Fed into Smart Grid networks, those readings could provide a detailed timeline of activities occurring inside the home. This data may point to a specific individual or give away sensitive data. This isn’t just a worry for the home marijuana farmer with a huge array of grow-lights. Finding out how much energy a manufacturing plant consumes per shift can be an element of industrial espionage.
Additionally, privacy issues arise from the question of the legal ownership of the data being collected. With ownership comes both control and rights with regard to usage. If the consumer isn’t considered the owner of the data obtained from metering and home automation systems, the consumer may not receive the privacy protections provided to data owners under laws as they are written today.
SECURITY
Security is an even greater concern in an age of vulnerability to terrorism. Remember, we’re talking about the generation, transmission, and distribution of prodigious amounts of energy. Overall, the risk is high because Smart Grid information and controls flow through so many networks with so many owners.
To deal with that, NIST leads a Smart Grid Cyber Security Coordination Task Group (CSCTG) with more than 300 volunteer members from businesses, universities, regulatory organizations, and federal agencies. Cyber security requirements are being developed using a high-level risk assessment process. NIST has published a preliminary report, “NIST Interagency Report (NISTIR) 7628 Smart Grid Cyber Security Strategy and Requirements,” that describes the CSCTG’s overall cyber security strategy for the Smart Grid.
SGIP
A new phase of the NIST plan has been formalized as the Smart Grid Interoperability Panel (SGIP). By mid-December 2009, one month after it was established, the SGIP membership exceeded 400 organizations divided among 22 stakeholder categories.
The SGIP’s function is to support the ongoing evolution of the Smart Grid Interoperability Framework; to identify and address additional gaps; to reflect changes in technology and requirements in the standards; and to provide ongoing coordination of SSO efforts to support timely availability of new or revised Smart Grid standards.
Comprehensive information on the stakeholder makeup of the SGIP, its meetings, and its findings is available at the NIST Smart Grid Collaboration Site.
A key element of the SGIP’s efforts is to ensure that a compromise in one network does not compromise security in other interconnected systems. A security compromise could impact the availability and reliability of the entire electric grid.
This introduces further opportunities for designers. Devices and applications in each domain are network end points. They include smart meters, appliances, thermostats, energy storage devices, electric vehicles, and distributed generation equipment at consumer sites.
Other devices in the transmission and distribution domains include phasor measurement units (PMUs) in a transmission line substation, substation controllers, distributed generation, and energy storage. The operations domain includes supervisory control and data acquisition (SCADA) systems and computers and display systems at the operation center.