Open systems: The foundation for a new era of BAS

As system integration strategies become more complex, the need for improved building automation system specifications becomes evident.

By Ron Bernstein, RBCG LLC, Encinitas, Calif. April 1, 2013

Learning objectives

1. Understand open and closed building automation systems.

2. Learn about system integration, system specifications, and their complexities.

3. Understand the roles and responsibilities of vendors, consultants, and integrators.


Throughout the past two decades, the building automation system (BAS) industry has witnessed the introduction, incorporation, and acceptance of open systems (see sidebar, "Definitions and terminology") as a practical-and largely preferred-solution for system integration and enterprise-wide interoperability. As the industry moves farther away from proprietary or "closed" systems, the market opens a new level of opportunity for vendors, consultants, and integrators to engineer specialized products and craft solutions that utilize widely available technologies and provide cross-platform accessibility.

There is plenty of room in the market for innovation with an open systems approach, and those who embrace it are free to innovate the next generation of intelligent and interoperable buildings. Success will be measured by the level of interoperability, transparency, and acceptance by end users. By adopting a multi-tier division of responsibility and validation process, a sustainable check-and-balance system can be put in place. This article discusses these concepts and how they apply to a single building, a collection of buildings (campus or site), and a full enterprise solution. The enterprise is the highest level of abstraction and supervisory access: think SCADA (supervisory control and data acquisition) for hundreds or even thousands of facilities!

Specifications that deliver open systems

As integration strategies become more complex, the need for improved specifications becomes evident. The opportunity arises for consulting engineers to increase the value of their business by providing more comprehensive BAS control specifications and work with owners to define corporate standards and openness, and improve cost of ownership. Generic specifications that simply require a system be "open" are no longer acceptable. Specifications must address a sophisticated level of integration, cross subsystem interaction, IT integration, and data management elements so owners have clear ownership and access.

Learning the basics of what makes a good specification requires more information than just a mechanical or electrical system specification. The process starts with a clear vision and objective followed by a well-defined project scope. It will provide context for the project, help the engineer create the specification, and set a foundation for the team to get on the same page. Industry suppliers and integrators are engaged to ensure adoption of and compliance to the specification. This step is followed by a verification and validation model where adjustments are made as needed.

According to John Huston, President and CEO of Division 25, a consulting engineering firm based in Chicago, "The biggest issue is education. Unfortunately, the BAS design market hasn’t required many extra demands over the last 30 years or so. When older systems were initially created, they were proprietary, and engineers got used to designing very generic systems. But today, technology has evolved significantly, and engineers must learn what these technologies are and how they can be properly integrated so they can do what they’ve been hired to do, and that’s providing expertise to their clients.

"The role of our firm is to serve as a technology partner, and this inevitably leads to educating our clients on the options available to them, and doing so on whatever level they are most comfortable. As the technology partner, we fill in the gaps where the client lacks expertise or simply doesn’t want to maintain internally."

To help address this issue sample guide specifications are being created that incorporate all the necessary integration elements as a starting place for consulting engineers. This work is being done in the ASHRAE SGPC-13 Standing Guideline Project Committee, a team of industry experts developing a standard guide specification for use by system designers, consulting engineers, and end users with the goal the goal of having a draft ready for public review in 2013. The guide specification outlines the responsibilities of the integrators and associated vendors. It does not mandate a specific technology or protocol. In fact, there will be references that provide options for both a LonWorks and a BACnet system. In some cases, solutions may require both in the same facility, and this will be accommodated.

Combining technologies

The expansion of the open systems model to multi-protocol, cross-subsystem integration in both single- and multi-premise applications is becoming the norm. Owners want the best the market can offer, and sometimes this requires a combination of technologies to achieve the desired result. New systems are embracing a variety of subsystem architectures that employ an assortment of devices and communication protocols. But these solutions must "play nicely" together in order to provide the necessary ROI and longer-term cost benefits. Systems utilizing industry standard communication protocols such as LonWorks, BACnet, Zigbee, Z-Wave, EnOcean, and OpenADR, all of which have or will achieved ISO standardization designation, will become commonplace, and all of these protocol based subsystems must be able to interact and work together.

Active investigations are under way to tackle this hurdle including several independent efforts such as the EASI project (Enterprise Application Standard Interface-an independent group of end users, owners, vendors, and developers) working on a open architecture solution, which addresses the communication between the lower subsystems and the enterprise by providing common application program interface (API) and data profile models for information. Other initiatives, such as the Haystack project (also an independent group of vendors, developers, and users), are looking to address the common labeling, tagging, and point identification issues that can help with the standardization of information models as disparate systems are integrated together. Other standards bodies, such as the OpenADR Alliance (automated demand response), are looking at solutions that focus on the communication levels between the building and the utility to manage energy consumption.

According to Barry Haaser, Executive Director of the OpenADR Alliance, "Demand response (DR) programs help utilities maintain grid reliability and enable customers to realize significant value. Unfortunately, existing propriety solutions add unnecessary cost and complexity. The OpenADR Alliance was created to standardize, automate, and simplify DR to enable utilities to cost-effectively meet growing energy demand, and customers to control their energy future. The importance of BAS and DR integration is paramount to the success of the Smart Grid."

Dividing the vendor roles

An open philosophy sets the stage for vendors to focus on their area of expertise and work with other providers to deliver a complete solution, one that allows building owners to select the right products and vendors for their needs. In this strategy, the integrator role is elevated to oversee the complete project and ensure the building owner’s objectives while separating the vendor roles so no one vendor is supplying the entire solution. Many building owners have implemented a multi-tier system architecture that defines these roles, where tier one is the sensor/actuator level; tier two is the field devices, such as the controllers; tier three is the in-building communications and connectivity level including device communication protocols; and tier four is the IT and enterprise infrastructure including user interfaces, both local and remote, data collection, and analysis. By utilizing the four-tier model, a check-and-balance system is put into place that ensures fully transparent interoperability throughout the system.

Embracing IT

The proliferation of IT into nearly every aspect of our daily life illustrates just how efficient and productive we can be with data readily available to us. The BAS industry is no different. As building owners discover what it means to have an open system, they see how intelligent decisions based on usage data positively impact the bottom line. While the definition of "open" may differ from one person to another, the common thread is data and its level of interoperability and accessibility. Couple this with an open protocol that facilitates the access to data across different systems and platforms, and this opens the door for the facility and IT departments to cooperate in the design, implementation, and management of the BAS.

Access to data from anywhere requires even greater support in the base system specification. Tying a BAS system into the facility IP network may seem simple and straightforward, but as soon as the IT department gets involved, a host of issues become exposed as the BAS system encroaches into the IT space. More and more control devices feature native IP access ports, requiring a fixed IP address. The IT department must be aware of and prepared for increased bandwidth utilization and, of particular importance, the security risks.

In 2004, the U.S Army Corps of Engineers published the Unified Facilities Guide Specifications, a definitive specification guideline that identifies building and integration requirements with the ultimate goal of creating "one integrated, multi-vendor system with no future dependence on any one contractor or controls vendor." The guideline encourages competitive bidding at all levels of procurement, and it has been adopted by thousands of installations nationwide. According to Will White, lead project engineer for the U.S. Army Corps of Engineers, "Security on our building systems is critical, and we are actively and aggressively defining the systems and standards to ensure the highest level of security is enabled. This may put an additional burden on the integrators and their vendors, but will enable us to expand our strategy into a fully enterprise-based solution rather than the current, single-premise-based solution."

Efforts within several standards groups are engaged in defining the hardware and software requirement for various levels of security. SGIP 2.0, Inc., is providing a national framework for coordinating all Smart Grid stakeholders in an effort to accelerate standards harmonization and advance the Interoperability of Smart Grid devices and systems, including security issues for tying the smart building into the Smart Grid. Other organizations, including LonMark International, ASHRAE, OASIS, and others, have developed security task forces to begin addressing the specific issues faced by building automation systems.

Cloud computing

As BAS and IT integration issues are addressed, the use of cloud computing becomes an attractive opportunity for real-time data management. In a cloud scenario, data are stored in remote servers in a manner that is accessible anywhere, anytime. For integrated control systems, this is achievable only if the system design and specification define that access.

"Open protocols are enabling us to tie these variables together by utilizing one standard platform, being able to aggregate those data into the cloud. Cloud computing has become so mainstream that by integrating all the data into a cloud database, we are able to utilize that information across multiple platforms," suggests Jason Alvarez, president of 8760, Inc., a system integrator proficient in open systems. "So, when it comes to balancing between the Smart Grid, demand response, performance optimization of buildings, and so forth, these applications are all pulling from the same source of information."

Alvarez explains how his firm uses cloud-based technologies to access and analyze the data, providing them to the owner in simple reports that identify trends and system anomalies on which the owner bases operational decisions. This vendor-based approach allows owners to "subscribe" to the data they want to see and how they want to see them.

While there are good economies of scale, such as reduced maintenance of onsite computers and improved system flexibility, cloud computing faces a perception issue that must be overcome. Owners still want to "own" their system, and if the data and servers are remote, this comfort level must be addressed. To bridge concerns of data ownership, savvy integrators are providing solutions that combine both local and cloud storage.

Building Clouds, LLC, President Robert Wallace says, "Cloud-based access of building automation systems allows our clients access to a wide variety of analytics, reporting, trending, and control from a web-based user interface. Uptime and security are critical for our customers, so ensuring the service is hosted at the most reliable data centers is fundamental to our business model. Customers like the idea of us maintaining their infrastructure, but also like that we can provide local access as well as cloud access to their systems. Flexibility and choice are key."

As solutions start embracing more remote and cloud access, improved security standards using the latest firewall and encryption techniques are necessary. Recent awareness of security holes in certain solutions has raised the bar, and integrators and vendors are now taking this much more seriously. Opportunities for security solutions in the IT space are filtering down to the BAS space, and the best way to incorporate heightened security measures is including criteria set by the IT industry in the specification. This further underscores the importance of IT and BAS professionals working together to understand each other’s pain points and requirements.

Outlook for the future

It is an exciting time for the BAS market as the concept and scope of system automation and interoperability are expanding from the core single-building model into an enterprise model. System integrators, vendors, and owners are pushing the envelope, and the demand for open technologies and solutions has become the norm. As more subsystems are integrated into buildings, more buildings integrated into campuses, and more campuses integrated into the enterprise, the definition of the "system" is becoming blurred.

To accommodate this growing market sector, more holistic system designs and specifications are critical. Today, BAS systems must peacefully coexist with IT, which requires collaboration between the IT department, facility managers, system architects, and engineers. Together, these elements of change will provide significant opportunities for engineers, vendors, integrators, and users who will create a new standard of intelligent, integrated buildings. 


Ron Bernstein is president of RBCG LLC, a company providing consulting services for building owners, users, integrators, and engineers. He is also the chief ambassador of LonMark International. 

Resources for open specifications

Whole Building Design Guide – National Institute of Building Sciences

US Army Corps of Engineers = Unified Facilities Criteria (UFC) 

The Smart Buildings Institute – Educational Courses