by Erich Gunther, IEEE
One could argue that building automation and the utility-to-commercial building space--let's call it Smart Buildings 1.0--has matured. The initial concept focused on energy efficiencies, demand response opportunities and how enlightened practices, aided by technology, can improve the bottom line.
The next iteration of this idea--let's call it Smart Buildings 2.0--is when business continuity assumes greater importance. This is less about efficiencies and more about corporate energy destinies. That implies greater control over a commercial entity's generation sources, the ability to island and net-zero energy use. This approach includes the ability to maintain operations, and thus productivity, in the face of events such as natural disasters, extreme weather, attacks on the grid, accidents, mistakes and other disruptions. Corporate managers and shareholders increasingly recognize that companies without business continuity plans and the means to enact them face significant, yet unnecessary risks.
Commercial buildings, like industrial concerns, were among the first grid-tied entities to take advantage of interval meters and the dynamic rates.
The result has been the development of in-building technologies to respond to dynamic rates in the form of automation for building systems, controls and monitoring for optimal efficiencies, as well as to participate in utility-based demand response programs. Entire associations, even cities, have promoted these improvements in energy efficiency successfully to the benefit of their constituents. Automated smart building controls have an established business case that's well-recognized. That effort has gone mainstream.
Expect more of the same to spread across the country and around the globe. What well-managed company wouldn't seek substantial savings? Still, progress is needed. Vendors of automation and control systems need to fully embrace standards that enable interoperability for all the traditional reasons. In this instance the traditional reasons--simplicity, vendor choice and market growth--are augmented by a technical one. Today's plethora of interconnected, proprietary automation and control systems and the legacy systems they're built on depend on gateways that allow systems to talk to one another, impeding the speed of signals that need an unimpeded path.
The next generation of policies, programs and technologies will reflect that it's good to be green. More important, tangible value flows from steps taken to ensure business continuity. In a holistic view, these advantages are inseparable. It's good to maintain productivity for the sake of the bottom line and shareholders' returns, and that is positive for a company's brand.
That's what's happening in a California project for a large corporation with designs for a substantial new campus that will house a large, highly productive team of people for whom interruptions create substantial losses in productivity and profitability. When a temporary outage hits a business, there are widespread complaints about the interruption, the possible loss of data, and then, employees gather in the halls to talk. Even if the power is restored quickly, the interruption has impacted productivity adversely.
In a 2001 paper published by the Electric Power Research Institute, "The Cost of Power Disturbances to Industrial and Digital Economy Companies,” authors David Lineweber and Shawn McNulty reported that power quality aberrations and outages cost businesses in the United States an estimated $119 billion to $188 billion annually. Between 2001 and 2010, major outages in the U.S. doubled, according to the Energy Information Administration.
These findings underscore the impetus. For example, power quality fluctuations and interruptions cost money to companies and the economy. Major outages related to natural phenomena, such as Superstorm Sandy, appear to be increasing in frequency. Utilities have begun the decades-long process of modernizing the grid, and individual businesses also are taking steps.
The goal is a corporate campus with buildings whose energy systems must operate in such a way that typical, momentary, grid-related outages don't affect workers and remain unnoticeable. The campus, however, must be able to withstand events that could cause a loss of electricity for days to weeks, such as an earthquake, an extreme storm or a malicious attack on the grid. The system will be designed to permit participation in various markets, including peak shaving, demand response and ancillary services, which further adds to the business value of the project. The facility also is environmentally friendly, and a net-zero energy building allows the company to bolster its image as a green company with altruistic and market-driven motivations.
The current design of the campus calls for a net-zero energy outcome that relies on energy efficiency, energy conversion, on-site renewable energy sources, on-site backup power and ties to the grid for backup power and to enable the periodic export of excess power. The campus will have renewable energy power purchase agreements with energy service providers served by the local utility through the California Direct Access program to ensure that whatever electrons it needs to purchase come from renewable sources. The on-site backup power system also includes fast-start diesel generators.
Rotating Mass Still Needed
Despite the effort to make the campus a net-zero energy proposition with minimum reliance on fossil fuels, fossil fuel-driven gas or diesel generators remain a key component of backup power. Rapid balancing of supply and load in this potentially dynamic environment relies on the fundamental physics of a rotating mass--a machine such as a diesel generator that can maintain the balance of the electrical system at 60 hertz. The campus, to a degree, reflects the demands of the greater grid around it. The diesel generators also play a role in providing power in relatively long-term contingencies. The traditional rotating machine is key in ensuring there is enough short circuit current available to allow protection systems to operate correctly when on or off grid.
In a small-scale system, a rotating mass isn't needed to balance supply and load. Backup can be achieved, albeit expensively, with a large battery. As scale increases, so does the need for rapid balancing and fail-safe contingency power. Fast-start diesel generation is mature technology, yet the power electronics that play a key role in automation and control of the campuswide energy system are immature. The trick is to optimize the mix of energy sources to meet cost-effectiveness in a rational business case.
Business continuity, whether a disruption is momentary or extended, means requiring a microgrid. During an outage, this approach requires the rapid start of alternative power generation, commonly referred to as distributed energy resources, and the prioritization of campus baseloads, plus balancing the two. Another element in this picture is a master controller with situational awareness.
The generation side might require orchestrating battery banks, managing biogas-driven fuel cells so they remain online during an event, kicking on fast-start diesel generators or tapping other energy sources that can be ramped quickly to replace grid power. Load-side actions include using pre-programmed priority schemes that can adjust end use to maintain critical systems while lesser priorities are shed to help balance supply and load. These actions require a system-to-system signal path that must operate in milliseconds to maintain business continuity without interruptions perceivable by workers. Three aspects of this approach remain works in progress: the building automation controller, a building automation system that can respond in a timely fashion and power electronic interfaces between elements of distributed energy resources.
Existing Standards Can Serve
The number of systems and components involved require gateways to allow systems and boxes to communicate. Gateways and boxes, however, delay signals. Performance metrics require deterministic, unimpeded signal paths. For buildings to benefit from automation and controls and for microgrids to do work seamlessly, controllers must react to conditions and apply logic to options as fast as possible--a timeframe measured in milliseconds.
The best-known method to avoid delays in the signal path is to employ native interoperability standards to reduce the number of gateways and smooth the signal path across interfaces. Standards and interoperability are cited frequently in terms of economies of scale and market growth, but in this context they are technical requirements.
It appears ASHRAE's Standard 135-2008, known as "BACnet,” a data communication protocol, can serve this function. A building automation system should support OpenADR to accommodate a demand response signal from the outside world. A few existing standards are appropriate in this case, only needing to be deployed and incorporated natively so no delay exists in system-to-system translations or in recognizing inputs from outside systems.
Implications for Utilities
The local utility for this West Coast project isn't using its cooperation with the corporation and its net-zero energy campus as a showcase. The utility's business case, however, is not aligned with the customer's. For the utility, a net-zero design at a major commercial customer's campus is a troublesome load. And there's little incentive for the utility to provide the infrastructure and energy supply for what becomes a net-zero load or to provide the means to accept that campus's export of excess renewable energy. A utility business model that is dominated by energy charges isn't rewarded. That dynamic simply highlights the need for new business and regulatory models for the utility industry. Smart Buildings 2.0 is only going to grow, and corporations that follow that path can take that to the bank.
Erich Gunther is an IEEE Fellow, former chairman of the IEEE Power and Energy Society Intelligent Grid Coordinating Committee, chairman emeritus of the Department of Energy's GridWise Architecture Council, chairman of the board of the Utility Communication Architecture International Users Group, and chairman and chief technology officer of EnerNex.