“Today, Building Automation Systems containing more than 50,000 data points are commonplace. The sheer volume can be overwhelming and counterproductive. Building Analytics provides facility staff the “power tool” required to automatically and efficiently distill this data into actionable information.”
Source: TIME The Military Engineer by Ken Robinson
Building Analytics represents a fairly recent technological advancement within the building automation industry. Building Analytics (BA) can be generally described as the perpetual search and notification of significant abnormal or undesired patterns in data. While an automation system provides information on temperature, air flow, energy usage and the like, BA provides additional insight necessary to fully understand what is truly going on within a building. BA is used for anti-degradation, continuous improvement, prioritization of maintenance and repairs, fault detection, normalized reporting, and categorized and prioritized notifications. BA also assists in troubleshooting and creating repeatable procedures.
Over and above these functions, BA can play an important role in maximizing the benefits of an Energy Savings Performance Contract (ESPC) in areas ranging from project development to savings preservation.
A BETTER VISION
When developing and implementing an ESPC project, perhaps a BA platform’s most valuable function is the ability to rapidly assess the performance of all energy-consuming systems; in turn, helping to create a master plan for these system upgrades. This ability to craft the vision of a future high-performing facility can be an essential guide in determining not only specific Energy Conservation Measures (ECMs), but also determining the optimal timing of their implementation and financing strategies to minimize installed costs and maximize the owner’s cash flow.
BA can quickly reveal existing building loads in terms of electricity and thermal energy use, such as chilled and hot water, and benchmark those loads against “typical” buildings and also “best-in-class” facilities. Analytics also can pinpoint potential issues with distribution systems, opportunities for active load and demand management, and magnitude for on-site energy generation such as solar or Combined Heat & Power (CHP).
With this information in hand, it is much easier to assess which ECMs should be examined in more detail, and in what order they should be implemented. Getting the timing right can be a major source of savings that is often missed. For example, many facilities have aging central plants that create urgent concerns over service reliability. However, simply replacing the equipment will produce relatively modest savings even if the new equipment is significantly more efficient. The best approach is to reduce the loads first, which entails more detailed work to assess energy end-use. This reduction in end-use translates directly into a lower cost for the new plant, since the plant can be made that much smaller.
Using this “Vision First” approach can produce other benefits. We have seen instances on large campuses where new buildings are brought into service without expanding central plant capacity, even though such expansion had at first been considered inevitable. This was due to the ability of an ESPC to reduce energy use in other buildings by such a large amount that no new plant capacity was required.
“Vision First” also allows building owners to explore a variety of funding options. By knowing, at least approximately, the future costs and savings associated with different scenarios, owners can compare options which may be incorporated into a broader ESPC process.
When developed properly, ESPC projects can provide tremendous value in terms of reduced energy use, improved resiliency and better infrastructure. BA can contribute strongly to creating the vision within which ESPC projects can be guided to the best possible outcomes.
LESS IS MORE
A good BA package can do much more than help craft the vision for a facility. In terms of an ESPC project, the detailed audit, technical assessments and design engineering constitute a time-consuming and critically important series of steps that can be both shortened and improved when an Analytics platform exists.
Most facilities have some data, but there is no such thing as too much data. Copious, accurate data on existing energy use and patterns of use provide valuable insights into the current state of a building’s operation and how that facility compares against other buildings on the same campus and in general.
Output from an Analytics package can reduce the time required to properly assess a building’s current state, and improve the quality of that assessment. It lessens or removes the need for an ESCO engineer to input huge amounts of utility data into a different tool for analysis, thereby lessening the chance of human error.
One of the least recognized elements of a successful ESPC project is the creation of a detailed baseline. A project’s savings will be calculated as the difference between the prior state of operation and the new one. It is critically important for building owners and ESCO to have a solid, mutual understanding of exactly how the baseline is defined.
Baselines are much more than simply summing energy use over a given time. Good baselines establish details of service levels such as space temperature and humidity, system operating hours, static pressures, air flows and air changes per hour, occupancy hours, and much more. These parameters vary greatly from one building to another. A BA package can capture and document all these elements, both before and after construction. In addition to the important role this plays in the early years of an ESPC’s performance, in future years it can help educate new personnel who are not familiar with the project’s history.
Optimization is the process of automatically controlling a complex system to maximize energy efficiency without compromising operational performance. Before a system can be optimized, it must be capable of stable operation and control. Accurately and efficiently identifying deficiencies can be extremely complex and time consuming. Building Analytics provides a streamlined mechanism for identifying and assigning priority to deficiencies while also discovering optimization opportunities that are often not recognized by a simple review of BAS trends.
This process of system optimization can be done independently of an ESPC project, and Building Analytics are often used to do just that. At the same time, the optimization capability afforded by a good BA package dovetails beautifully into an ESPC process, ensuring that the sequences developed for the newly installed systems are not only implemented, but are actually achieving the desired outcomes in terms of occupant comfort, service levels and energy savings.
RETURN ON INVESTMENT
All good building engineers strive to maintain safe and comfortable environments for the users of their buildings. They will not, and should not, compromise these standards for the sake of achieving a set level of energy performance. Buildings do not exist to be made more efficient; they exist to allow their occupants to function as effectively as possible.
All too often, however, off-the-cuff responses to occupant complaints lead to shifts in operating sequences that go well beyond what is necessary to correct minor problems with building comfort. We often encounter systems with incorrect setpoints, reset schedules, start-stop times or even with manual overrides of normally automatic functions such as fan speed. In addition, systems themselves deteriorate over time. Sensors and actuators drift out of calibration and mechanical devices start to lose positional accuracy. The inevitable result is increased energy use.
A good Building Analytics package is perhaps the best tool available for catching these types of system degradation before they get out of hand, and ensuring that the savings achieved by an ESPC project are preserved. What this means is that the investment of time, effort and money that goes into a large ESPC job maintains its return over many years.
Ken Robinson is Director of Business Operations, Southland Energy; firstname.lastname@example.org.