Distinguishing Building Service Semantics from Ontologies

Building service performance is not handled well during building design because there is currently no accepted way for owners and designers to discuss the services desired and the performance expected for each service in simple general terms. Construction processes deliver diverse technical systems each discussed using concrete physical attributes whose effects are understood through a deep domain knowledge not often common to either owner or designer, or even to different contractors. This leads to specifying materials and processes rather than results, is ineffective in defining success after commissioning into long term operations and maintenance.

New demands that buildings interact dynamically with entities other than the owner and operator will soon require that provisioning of services be managed over the lifecycle of the building rather than merely for procedural completeness at building turnover. These external entities include power provision and emergency management. The transacted power grid will expect buildings to negotiate with remote, local, and internal energy suppliers to meet the needs of the occupants. Emergency Management will expect buildings to respond to environmental alerts, i.e., tornado warnings, to provide situational awareness after an event.

Over at ONTOLOG, several of us are formalizing new semantics to enable discussion of building services and their quality. These words will provide a common basis for discussing service between all actors over the life of the building. They will also provide the groundwork for buildings to interact with actors external to themselves.

If we do this right, these semantics will become the basis for interacting with BIM. Each area of knowledge and practice within the Building Information Model (BIM) has a formal interface to other areas of the BIM. This interface allows information to flow both ways. Information flows into an area to define goals and constraints. Information flows out of an area to provide results and requirements. This allows for multiple processes within each area. During design, the goal is to let the owner participate in decision earlier in the process. Imagine the following scenario.

During design, a six story building is designated as commercial space on the ground floor, a restaurant on the second, and office space for the next 4 floors. Quality indicators for all three types of space rely on the Effective Ventilation Index (EVI). Commercial Comfort Index is defined based upon room temperature, humidity, occupancy, and EVI. The standard for a strip mall is 1.0. The lessee, a high end store, requests that a CCI of 1.2 be provided, and documented by the underlying systems, and that it be done at a watts/square foot no worse than industry standard. The restaurant is divided into seating area, which uses the standard CCI and the catering area, in which a higher EVI is required by regulation. In the seating, the CCI must take into account the higher density of sitting customers as compared to the retail space downstairs. Office space is quite competitive and the local market has high vacancy rates. The owner wishes to promise Office Worker Alertness index greater if 0.8 (prevailing standard is 0.64) to achieve reduced vacancy in the prevailing market.

I shared this vision with Bo, a seasoned real estate professional who remains one of my more skeptical audiences. He vigorously objected. To Bo, a developer might choose to distinguish itself though having many more air turns per hour than the competition. They would still want to discuss the value in the same terms, but would not wish to be held to the same engineered standard of comfort. Bo vigorously objected to a mathematical standard for the comfort index….

This threw me for a loop. Then I recalled some spirited discussions from the Business Process Execution Language (BPEL) groups. BPEL is the language for passing a work flow or business process around using web services. There have been spirited discussions about BPEL, including conversations that claim that BPEL is not useful because business process is the proprietary advantage of any business, and so therefore real business process will never be passed around. This seemed to align with Bo’s comments.

Let me reprise semantics and ontology how I use these words. Semantics are the words used to describe things. When similar things get the same name, we are making semantic decisions. As people, semantics let us discuss the services provided by a system, and to compare and contrast how well those services are provided. To systems, semantics create a basis for interoperability and the creation of Services. Ontology, or meaning, is a way to discuss a value of the services; ontologies are variable. Crudely, accounting is a semantic system; cost accounting and financial accounting are different ontologies built upon common accounting semantics.

If we take this model, than I agree with Bo. The concrete basis for value in building services require a common semantic framework. At the highest level of abstraction, these services slide into ontology, where the building operator defines value. The building operator, or even the building designer, must be able to define value, to define the construction of the top level semantics.

And that is the swing between building service semantics and building service ontology.

Abstract, yes, but which abstractions…

Building systems do not often produce useful information because they usually serve up concrete data, not abstract information.

Data is that annoying stream of consciousness woman who sat next to you on the bus. “Now my arm itches. Look at that girls over there; didja ever see a dress like that. I have something in my shoe. That man is looking at me funny. My nose itches. I hope I don’t miss my stop. I wonder if the fish at the store will be fresh. The fish last week was not fresh. My bra is uncomfortable.”  You really can’t do much with data, unless you know a lot about its source.

Information conveys something that is actionable. This means that all of the background details have been stripped away and you are presented with something simple, something that offers a choice.

Right now, there is great concern about information and choice about energy as a matter of national policy. Many measures are being presented as the basis for policy and law. Social and editorial arguments are being made about metrics and information. One element I am thinking of is, is fleet mileage and miles per gallon (MPG).

Richard Larrick and Jack Soll have just published a study of decision making using the MPG standard on cars. They have concluded that when presented with multiple choices, people usually make the wrong one when presented with MPG, and indicate that people would make much better decisions if presented with GPM, (or perhaps Gallons per 100 Miles).

You see, if we can move 10% of our automobile fleet driving SUVs from 12 MPG to 14 MPG, we will have a much greater effect on total gas used than if we move a different 10% of our fleet from 38 MPG to 44 MPG, assuming both segments drive the same miles. My readers are a numerate bunch – do the math; it is bet to upgrade the least efficient vehicles. People presented the same information expressed in terms of Gallons per 100 miles, have a much greater tendency to make the correct choice.

Now if everyone switched to driving 44 MPG cars, it might be better still, but that is not likely to happen. The people who sneer at hybrid SUVs may be off the mark, because there may be a lot more value for society in hybrid SUVs than there is in hybrid coupes.

Even though it grieves me, as a Carolina boy citing work from economists at the Fuqua School of Business at Duke, I recommend checking out the article in the June 20 issue of Science.

Regular readers know that I am interested in developing simple numbers to represent building performance and service provision. This study provides a caution. Even if we get the variables correct, deciding which is the numerator, and which the denominator may be critical…

Social interactions will define success of Electric Cars

This was the post I started writing a couple days ago until the first paragraph just metastasized to fill up the page. Once we have more than a few electric cars in town, then those cars will be potentially the biggest stress on the grid.

The peak stress on the power grid starts during the afternoon, during heat-of-the-day air conditioning and work, but it continues through the early evening. Offices are still turned on. Programmed houses are kicking in with their air conditioning in preparation for their owner’s arrival. Families are cooking dinner. The power grid is still working nearly as hard as it can.

Now let’s posit the electric cars coming home, drained from a day of driving. Perhaps they were doubly drained, used to carry their office buildings during the afternoon brown-out. What will people want from their cars next….

• To sit in the garage overnight, slowly charging.
• To be ready to drive 15 miles in twenty minutes when I go get one last kid from athletic practice.
• To be at least half charged and ready for anything in two hours when the baby sitter arrives and mom and dad head out for an evening on the town.
• To quickly get to at least a 40 mile range in case I get an emergency call from the nursing home, and thereafter just be sure to be ready for the morning commute.
• To get a charge for 15 miles by 8:15 when I head to choir practice at church. Better make that 25 lest we stop for coffee afterward.
• It's two hundred miles to the beach and we plan to take full advantage of the expensive week-long rental by getting there tonight! Kids, grab your bags, we are leaving in 20 minutes. Oh, and the car needs a full quick-charge, no matter the expense.

Gasoline handles all these scenarios. Many of them involve discretionary electricity purchases during the early evening peak. We will never solve these problems at the level of machine-controls. We need time of day pricing, to allocate the scarce resource. Just as many restaurants offer Monday-night specials, we need day-by-day pricing, to encourage people to choose when to schedule their evening activities. Electric cars will require live power pricing, by the minute, and by the day.

Let’s consider driving the electrical car further into our lives, and further into our infrastructure. Sometimes I will want to charge my car when I am not at home. This will require that cars identify who they are at the plug.

• When parking downtown, I want to plug in my car. I may want to choose between a quick visit, for a cup of coffee, and an all-day back-to-school shopping event.
• The Green Garage™ offers locally generated wind power for re-charging at its own special rates that vary with the wind. Having been burned once, I want to check prices before I leave the car.
• When I go over to your house for dinner, I want to plug in. Being a polite guest, I of course want the charges to go onto my own bill.
• The whole family gathers in the next town for Thanksgiving dinner. All cars are drained, and need to recharge over the next five hours except for the college kid, who arrives at the last moment, and leaves as soon as he can. Grandpa decides to overrule all normal agreements and cover all the charges for cars plugged in at his house.

The technical feat of creating amazing batteries and lightweight materials, however astonishing and inspiring, will be undone without the capability easy interaction with the lives and aspirations of those who drive the cars. Electric cars will require powerful intuitive systems interfaces, able to learn their owner’s tastes and habits. These systems can only interact with the power grid through simple standard economic interfaces.

Electric Cars will not be useful for Demand-Response

If a performing electric car were to arrive today, with adequate batteries at reasonable cost, it could well push today’s non-transactive energy infrastructure over the edge. Usually I write about intelligent building agents; when I write about the power grid, it is to discuss transacted energy purchases between those agents and an intelligent transaction grid. Today, I am going for those transactions on that grid, but leaving out the building. But first, a little on the building with cars.

There a lot of hopeful scenarios in which peak shaving is enabled by commuter cars plugged into office buildings. Peak shaving, initiated by what are called Demand-Response (DR) signals from the grid, is when buildings lessen their electrical demands to avoid peak periods of energy use. The story goes that we will go to work, and plug in our cars. When the DR event arrives, the building will run off the combined car batteries, reducing demand on the grid.

DR is very important for today’s grid, because the power supplied at the peak is the most expensive and usually the dirtiest to generate. I have seen numbers suggesting that as much as 17% of the grid’s capacity is used for less than 120 hours per year. If we manage peak electrical use, we have effectively grown the power grid for free.

Cars and their batteries, however, will never be an effective peak shaving tool for office buildings. Leave aside for the moment all HR-related issues associated with employers paying for commuting costs, and look at the people. Peak load occurs in the afternoon, and extends into the early dinner hour.

If I live some distance from my employer, will I be willing to end each day with a low charge on my car? Only until the first day I run out on the way home, perhaps because of an unanticipated need to attend a school event for my children, or to attend to a medical issue for my parents, or even to pick up some supplies for a social event. In any case, the first time it happens, I will resolve to park away from the building thereafter.

If I live close to work, I will arrive with my car already charged up. DR participation, always in the afternoon, will leave me always wondering whether I am subsidizing the company. The first time I am turned down for a raise, this thought will begin festering into a general resentment of my employer. Sub-vocal mutterings with phrases such as “blood-sucking leeches” come to mind.

Whether I live far away or whether I live close in, sooner or later I will leave early to head off for a summer (most DR events are during warm weather) weekend at the beach and find that despite my plans, my employer and its building have drained my car.

No, we cannot turn to electric cars to solve the DR needs of our office buildings. Not if actual people are involved. Perhaps if we make sure that our grid is intelligent and two-way transactional we can see a way past this.

I will try to write soon on what intelligence is needed, in grid and car, for more realistic use of more than a few electric cars.