Easy VRF & DSS Integration Solutions for BACnet, Modbus, Wifi
Bringing Schedules into Building Design and Operation
Facilities that understand their energy use will be able to control economic risk through committing advance purchases of energy on a schedule.
As WS-Calendar nears final publication, a number of efforts are underway to coordinate the internet of things, the processes of business, and the activities of people. As the energy supply becomes more local, and more intermittent, and more expensive, a better understanding is necessary of not merely how energy is used, but when it will provide an edge to the businesses that embrace it. I receive a number of inquiries about the incorporation of time and schedule into other specifications.
Operational BIM Schedules and Pre-Design Programming
Pre-design programming is defined in the Whole Building Design Guidelines (WBDG) as “architectural programming as the research and decision-making process that identifies the scope of work to be designed.” Programming is the first part of the design cycle, during which systems and space requirements are identified by the activities they will support. If the design process conforms with the formal BIM process (BuildingSmart, NBIMS, etc.), then these systems and spaces are identified as described in the IFCs.
BIM is a collection of information sets and models with identified interfaces / information exchanges between them. A model that is of growing interest is the building’s energy model, which is today derived from a combination of structural and purpose models and [normally] a side questionnaire about the building’s use.
I recently received early sketches (XML Fragments) of programming documents from Dr. Chris Bogen (Engineering Research and Development Center) in which building services and systems, as expressed in open buildingSMART model format, are included in vavailability to express, for example, the operating schedules of systems supporting dining facilities (and their energy requirements). The ERDC project is aiming toward the development of a format that to be used to compare the expected resource use of a facility during design and express the actual resource use identified through analysis of building sensor systems. With the additional pattern detection algorithms under development at the lab, ERDC expects to have a tool that will compare building use to identify when the use of a building doesn’t match its design prediction. The ultimate goal of this work is to create building simulators directly from data provided during traditional design and construction processes.
Schedule & Commissioning
Over time, many buildings are found to have different energy use profiles than their models predict. This is often due to changes in operating schedules from that originally predicted. We are beginning to see mandates to update these energy models to match actual results, particularly in government owned or funded facilities.
Lifetime maintenance and updating of these programming documents, including changing the operations schedules, establishes a baseline to compare predicted vs. actual use, and to thereby sooner detect anomalies due to system degradation or misconfiguration.
An advantage of potential automated modeling within incorporated availability, is that schedules can easily be understood and manipulated by building operators/occupants. Once an energy model is in-place, it would be straight-forward to iteratively try out different systems schedules and examine different energy profiles. As we move to dynamic markets, the capability to project different times of use and compare those to projected energy prices might become a new source of value to building operators.
Continuous energy models
Proper commissioning of building systems requires reviewing the [paper] plans, and interpreting the variations between design and as-built drawings, analyzing the building system tags, and developing an as-built energy model. Today, this work is rarely re-useable by others.
Energy models predict energy use, and building systems are responsible for the energy use in buildings; these systems typically do not change much after commissioning. A changing energy model is caused most often by a change in business practices. Live energy models must be mappable to changing occupant business practices. There is a growing sense that buildings should continuously update these energy models to maintain LEED certification.
LEED has been evolving away from easily game-able one-time checklists toward putting in place procedures and information that will influence long-term operating benefits. In December 2010, Dr. Krisnamurti at Carnegie Mellon University completed a project for ERDC to demonstrate the automated production of LEED models directly from open building information models. This prototype is available for testing from the buildingSMART alliance (http://projects.buildingsmartalliance.org/files/?artifact_id=3603).
NREL has recently released a report recommending tagging standards for building systems. This tagging standard is part of a larger recommendation on proper commissioning standards. The same report (http://www.nrel.gov/docs/fy11osti/50073.pdf) posits that a properly commissioned building system interface be able to offer up a light-weight building model, linked to these standard tags. This is required to make commissioning re-usable. This may become minimum commissioning requirement in a future version of LEED.
Business processes, though, are primarily linked to spaces, not to the systems. Some systems, i.e., food service equipment, may be linked directly to the business process; it may be that even these processes are stated most clearly through space use schedules. In a building with dynamic management of business processes, the energy models may need to be just as dynamic.
Smart energy will create new value propositions for those who understand the schedules when they will use energy. Smart energy communicates the volatility of energy supply and demand through prices. Facilities that understand their energy use will be able to control economic risk through committing advance purchases of energy on a schedule.
Operational scheduling of building systems in BIM promises to refine our understanding of energy use throughout the day. Linking building spaces to building systems will link energy use to business processes. Continuous commissioning makes energy models relevant throughout the life cycle of a building.
Performance Contracting and the new Commissioning
Information technology (IT) transforms industries and markets when it finds a way to scale the delivery of services. IT has a notion of scale in which marginal costs for providing a service drop to nearly zero; at a low enough cost, what may have been a high end amenity becomes a minimal requirement for all market participants. Because scale requires minimal startup costs for each new participant, scale increases competition by reducing the friction of changing service providers. Scale is the magic behind smart phones, personal computers, and the internet.
Building performance contracting today does not scale. It requires considerable up front work to understand the building before any value is delivered. These costs, both in money and time, require that each contract include a significant minimum contract length over which to amortize the up-front costs. These up-front costs make it uneconomical for energy contracting to use a third party auditor to verify results. If the owner selects a new a new performance contractor, the owner must incur the up-front costs again.
Proper commissioning as defined above creates an environment ready to scale. Imagine a market wherein a cloud-based energy performance contractor could offer same-day initial reports. Each of these parties can hook up to the BSI, read the BIM, read the tags, and begin analyzing right away. A potential energy performance contractor could offer the building owner a selection of third party auditors to report the success of the contract.
The low cost of startup creates a room in the market for a number of 3rd party auditors, also cloud based, able to provide independent assessment of the value delivered by the performance contractor. By reducing perceived risk, these auditors will accelerate the rush to scale.
The fierce competition between cloud-based services will drive rapid innovation: on one side driving costs down, on the other driving richer models. The information model of ASHRAE SPC201 will describe the energy use. Through the linkage of systems and space (as described in BIM) the models will directly tie energy use and business process. Schedule-based business assertions, as we are beginning to see in the links of WS-Calendar and the IFCs would make these models more business aware.
The end result of scale is always that only a few providers in each niche, fiercely competitive with each other. The companies that do not make it to scale end up missing the market entirely.
Retail use of Live Energy Models
The most respected retailers with superior operations are already tying energy use to short term activities, such as those associated with a sale in one portion of a store. That portion of a store with an ongoing sale may have increased HVAC driven by increased traffic or brighter lights to attract shoppers and display the merchandise, and other enhanced amenities. A side effect of the brighter lights may be increased heat load, thus causing still more HVAC requirements than at first expected.
In the fierce scale-based competition in the clouds, services that enable other retailers to work as the best do become a source of advantage. To be successful, these services must build on common frameworks, not because the technology demands it, but because they are the basis of consumer understanding for “how the services work”. Adaptive reuse of existing technology will speed adoption and acceptance.
The schedule-related assertions of the new energy models provide a basis for developing these services. They link operating schedules to building systems, and to space. They share semantics with the systems that schedule business and people. Different users will want different interfaces. The successful service provider will interact seamlessly with enterprise information systems from Exchange to Notes, and from Yardi to SAP.
WS-Calendar 1.0 is in the process of final publication by OASIS.
[Click Banner To Learn More]
[Home Page] [The Automator] [About] [Subscribe ] [Contact Us]