The Fourth Amendment and Smart Grids

If we are not careful, smart grids are in direct collision with the bill of rights. Some smart grid activities define or enable business practices for balancing energy supply and demand. There is a direct link between commonly accepted business practices and some definitions of our constitutional rights. With the best of intentions, we may be casually removing significant barriers to some of our most cherished freedoms.

The Fourth Amendment to the United States Constitution is the part of the Bill of Rights which guards against unreasonable searches and seizures. During the American Revolution, British forces made extensive use of writs of assistance, a sort of general search warrant that could be extended and used without ongoing review. In response, the Fourth Amendment created a standard whereby government searches must be issues only on a discovery of probable cause, and specifically limited in location and as to the matters being searched for, based on specific information supplied to a court.

The Fourth Amendment is the most explicit source of any support for privacy that I can find in the Constitution.

Dr Orin Kerr is one of the most respected legal voices on Fourth Amendment issues. Dr Kerr blogged this week on the relationship between technology, common practices, and developing standards for reasonable search (see reference below). Specifically, Dr Kerr was exploring the ten year old Supreme Court ruling in Kyllo vs. United States that defines the limits of police use of high technology in warrantless searches.

In cartoon form (IANAL), police scanned houses with some sort of IR scanning system and noted a hot spot in the attic. From the hot spot, they deduced that the defendant was growing marijuana under grow lights in his attic. Kyllo asserted that this was a prohibited search under the 4^th amendment. The question was, in effect, is a non-intrusive search using high tech an unreasonable search. Clearly, if Kyllo had been growing the marijuana in his front yard, there would have been no dispute when police noticed this when on routine patrol. Previous rulings had stated that police fly-overs are legal searches because non-police could fly over the property and spot the plants; the property owner has no reasonable expectation of privacy applied to aerial views of his property.

In this case, the search was ruled unconstitutional; Kyllo won. The Supreme Court adopted a test designed to let the result change with social practice: “when . . . the Government uses a device that is not in general public use, to explore details of the home that would previously have been unknowable without physical intrusion, the surveillance is a “search” and is presumptively unreasonable without a warrant.” Because infrared temperature sensing was not in “general public use,” the thermal imaging was a “search” that required a warrant.

Dr. Kerr was blogging on whether under this standard, the search in Kyllo was still prohibited. Remote infrared temperature-sensing has become quite common in a wide range of applications. I heard an ad on the radio yesterday for a remote home thermometer enabling mom to take a sleeping child’s temperature from the door without waking the child. Thermal images of houses to reveal gaps in insulation have become common; many utilities will pay for them as part of energy efficiency efforts. The question was, then, is this high tech device now considered to be in in “general public use,” and if so, can the police use it without a warrant without violating the Fourth amendment.

And so, at last, I loop back to smart grids.

Some business practices we are defining, particularly in what we are calling Managed Energy, can routinely monitor the activity of every device in a home. If we establish these practices as general practice, have we eliminated any Fourth Amendment shield against the use of the same techniques by police?

Analysis of electrical power consumption reveals more than you might guess. Research a decade ago explored what engineers could learn from these signals. One anomaly occurred almost every day in a home somewhere between a half hour and two hours after the owners left each day. Further research determined that the family dog waited each day until it was sure that its owners were really gone for the day—and then climbed onto the warm waterbed. They were detecting the change in the pattern of water heater use. Further research demonstrated an ability to distinguish how much activity was on that waterbed…

When we define business practices for the smart grid, we are doing more than solving a a difficult engineering problem. We may be creating practices that re-define our precious constitutional rights. Privacy is more than a best business practice for smart grids.

Distributed Energy Grids can use Diverse Energy Storage

But there’s no way to store energy, he said. What he should have said is that there are few ways to store energy at grid scale. Grids, and microgrids, have two approaches to storing energy. They can store it in something that produces electricity, or they can store it in any format that provides a service to its customers. The closer we get to the end users of energy, the more options we have to store energy. The most critical short term goal of smart grids might be to transfer as many incentives for energy storage to the end nodes of the grid as possible as soon as possible.

Very few of us want electricity—we want instead to have a modern life-style. This means we want ready access to sanitary services, whether clean water or working waste disposal. We want light, and heat (or cooling). We want our appliances to provide whatever services we bought them for. Digital electronics provide us with the most direct conversion of electricity to desirable service, but even there we may be able to store services.

Behind every meter there is a microgrid, which exists to supply the wants of its customers. The customers of transmission and distribution grids only want electricity, and they want a lot, so these grids are limited in how they can store energy. Any storage that these grids do use, must be big enough to support the transmission or distribution scale of operations. For example, pump storage, wherein water is pumped up in the air, and used for hydro-generation later, is a very efficient way to store the energy in electricity for later use. Transmission-scale pump storage, though, must be as big as a small lake. There are a limited number of locations to place a lake with a down-hill water supply where filling and draining the lake is an acceptable option. We may have used all of them in North America already.

There are not many more options for distribution scale storage in traditional local microgrids. Non-traditional microgrids, however, distribute more than electrical energy. District energy grids distribute thermal energy, whether in the form of heat (steam) or of cooling (chilled water). These systems can pre-cool (or pre-heat, although this is less common) water for distribution. Thermal storage lets district energy microgrids shift energy use to off-peak hours. In a modern transactive grid, such shifting can be part of demand response. Microgrids with significant thermal storage may be able to run entirely on site-based alternative energy during peak hours. They may be able to store off-peak generation converted to thermal energy.

Non-energy utilities have their own grids supported by the distribution grid. A significant service in cities is the supply of water, and water pressure. This is done by pumping water high into the air, using energy-intensive pumps. Water towers can easily become locations for energy storage, off-loading electrical use until when energy is cheap, and the pumps can run inexpensively. This local pump storage is not used to generate electricity, but within its limits is an effective way to shift energy use to times when energy is cheaper and more plentiful.

When the microgrid gets down to the size of a single commercial building or home, all sorts of energy storage options become available, if only we do not confine ourselves to electrical storage. High rise buildings pump water to so toilets will flush. Thermal storage can be in basements or rooftops. Some data center strategies could even be considered to be storing up business process for use later.

A Microgrid of One

The target of smart grid communications, particularly in collaborative energy space, should always be the microgrid. Some microgrids may contain a single home, or commercial building, or and industrial site—those are irrelevant details. Microgrids have a number of systems inside them that must work within the economic environment of that microgrid—and I am thinking of old economics, before the distinction of economics and ecosystem arose. Some microgrids may have a single entity inside, say a legacy BAS (Building Automation System), but the unitary microgrid is merely an artifact of the way we have always done it. The energy services interface is the gateway to a microgrid.

Microgrids contain collections of systems that may not share common technology. Some of these systems are small, self contained, and serve special purposes, such as appliances. Some are large and complex and span significant space, such as HVAC or an industrial line. Some look alike, are built from the same components, but have different missions; the laboratory fume hood and the air conditioning system are run for different purposes and have different constraints. Some may rely on different energy markets to do the same work; heat may come from electricity, gas, or solar thermal in the same building. Some systems may store generate energy used by other systems. All of these coexist in the ecosystem of the microgrid.

Diversity is the source of resilience in the economy and ecosystem. Monocultures fail badly in either. The diversity of systems in a microgrid is a source of stability. This is as true of the microgrid spans a campus or spans a high-rise. One source of diversity is diversity of response, which is tied to diversity of business service provided. A unitary system all too often has too few response options. Without expensive and non-standard integration, these simple systems are unable to expose nuanced and diverse services for manipulation by the humans, and human processes, they serve.

Diversity within kind (read Darwin for a definition) in building systems can come from multiple technologies (hard to maintain), or from multiple systems programmed quite differently (expensive to integrate) or from identical systems responding to different users. Diverse systems can be much more agile, just as individuals can be more agile than a committee. I posit that a collection agile systems is better able to respond to heterogeneity of environment, including unpredictability of power supply, than is a single committee of systems.

Diversity of services can provide new assets to the commercial building owner. Green leases seek to tie technology, capital, and performance together to please the tenant. Green leases require separate metering and operations for each tenant to be credible. Green leases in a high rise might work best with a number of identical systems, one for each tenant, rather than a monolithic system that responds only to all. Diversity is an amenity that enhances tenant service and leas ability.

How do we distinguish a microgrid from a grid? The external interface should be the same. Inside, microgrids are more intimate, they are the safe neighborhood the kids can go out and play in. Alternately, they may be more dangerous, the prison society in which no inmate must reveal anything. A microgrid defines a security context and a security posture. Intimacy and sharing and collaboration are all a part of some contexts—and not of others.

To me, the most interesting question of the week is what information do the systems within a microgrid need to share as they support their divers purposes and work within their mutual constraints. I know it starts energy usage, and predictions of energy usage, because that is the common resource they share within their environment, the basis of their economy and their ecosystem. I suspect they need currency, to negotiate their access to resources within the constraints of the microgrid—although I am not sure that currency is always expressed in legal tender. Some systems may only be able to buy at certain stores, or sell to certain buyers.

I’m not sure what else they share.

Standards for energy engagement and autonomous response (3b of 3)

The fourth of three planned posts on revisiting the smart grid priority action plans ran over long. The first post discussed semantic issues. The next addressed the conflict between the business models for Managed and Collaborative Energy. In this one, I discuss the architecturally significant interfaces of the smart grid, updating my earlier musing on SGIX. The third (3A) discussed the 4 key standards for coordinating energy use and supply. This one discusses standards for feedback and planning on the customer side.

SG Energy Usage

Energy use has traditionally been summed over a month and then received by the client weeks later, far too late to affect behavior. Recent high profile efforts by Google Energy and Microsoft Hohm have demonstrated the power of granting consumers access to near real time dynamic data about energy usage. Makers of building automation systems (BAS), particularly makers of heating and cooling systems, have long wanted direct access to current meter information. Two quite different standards efforts from two quite different trade associations are taking one standards for sharing energy usage information.

OpenADE

The UCA International user’s group (UCAIug) is developing OpenADE (Automated Data Exchange) to more readily share information through existing utility infrastructure. It begins with sharing day old interval data with customers and third parties, and will then strive to become more current. OpenADE leverages the standards of Managed Energy (described in my previous post). Although the long term plan is cloudy, surely the utilities are well poised to include demand response (DR) and other grid and market events with usage information.

EISA

The Energy Information Standards Alliance (EISA) is a new consortium considering energy usage from the perspective of the end node. EISA foresees much more frequent and timely information not only from the meter, but also from each intelligent system and appliance throughout the building. Each system will provide a type of energy metadata on systems that consume power. Think of the Google Energy demonstrations, think again of certain contributors to the energy profile able to report and to identify their own use.

One part of the EISA vision that appeals to me is the idea that autonomous building systems would compare energy profiles and smooth the overall load profiles; no two systems would produce energy spikes at the same time. Autonomous load shaping is important not only for the short term grid, but is also an important enabler of site-based energy, and even net zero strategies. Some members of EISA see it as a suite of standard oBIX contracts.

Standards Ancillary to Energy but useful to Smart Grids

Many of the benefits of smart grids come from improved situation awareness. The standards used within the grid itself, which I do not concern myself with, are largely to improve awareness of grid operations. Where I do concern myself, with the end nodes of the grid, those situations and that awareness reach beyond the grid itself.

UnitsML and SensorML

There are many things to be measured and sensed in industrial facilities and commercial buildings. Sensors may be part of systems or isolated. (I have some use cases that demand incorporating ancillary sensors into central energy management.) It would be good to use standards that describe the measurements unambiguously in ways that can be shared by multiple systems.

UnitsML offers an unambiguous way to describe all physical measurements, and an unambiguous ability for a computer to look up the translation of any units of measure to any other units. UnitsML is an existing OASIS technical committee with NIST backing which will need wider participation to complete.

SensorML is a standard from the Open Geospatial Consortium that can describe the geometric, dynamic, and observational characteristics of sensors and sensor systems. There are many different sensor types, from simple visual thermometers to complex electron microscopes and earth observing satellites. SensorML can describe them all.

Digital Weather Markup Language (DWML)

Knowledge of the future is important to all markets; knowledge of future weather is important to energy markets. All weather is local. Local weather awareness includes not only weather predictions, but also knowledge about the actual weather at my location following previous predictions.

DWML is an existing specification developed by the National Oceanic and Atmospheric Administration (NOAA). NOAA offers access to their National Digital Forecast Database (NDFD) using DWML. DWML is a little quirky, and a little hard to use. Smart energy would benefit from its further development. We need to define a DWML profile for reporting as well as forecasting, to enable the exchange of actual conditions as well as forecasts. Such a profile would be used when querying local weather stations and even personal weather systems.

WS-DD and WS-DP

Device discovery and device profiles have been used in computer networking for some time. These specifications for the web services implementation are going to a standards vote in May. A major manufacturer of electrical equipment has already announced that they will include WS-DD and WS DP for all the equipment it sells. There are open source implementations for small devices (https://forge.soa4d.org/). I think they will have a big role in the future world of distributed generation and Net Zero Energy facilities.

SG CyberSecurity

Cyber security is drawing more attention and concern every day. Today’s grid cybersecurity is concerned primarily with defending the isolated system with relatively static interactions. Tomorrow’s cybersecurity will apply to systems interacting with others owned by many different people, of uncertain skill and diligence in securing their own systems. Security issues need to be integrated within every smart grid standard from the beginning. We need a separate security toolkit/framework, perhaps a profile from current fine-grained security standards, key management, and related areas. Broader integration of physical security, fine-grained networking and commercial security, and situation awareness technologies need to be part of the mix.