AutomatedBuildings.com Article - Where do Whole-Building Analytics Fit in the Energy Professional's Toolkit?

New York City just announced a building retrofit plan to move it towards the goal of an 80 percent reduction in emissions by 2050. As municipalities and states make such public commitments, the pressure is on property owners to comply. This dynamic increases demand for energy benchmarking, energy audits, energy savings estimates, new construction and retrofit commissioning, among other activities related to improving the energy efficiency and comfort of building stock. Yet, while the need for building energy analysis is growing, the talent pool of building energy experts is limited. New whole-building energy performance assessment tools are one way technology innovators are trying to fill the gap.

Looking at any system from a high-level and as a whole is usually the best way to get to know its key drivers. The ability to assess energy performance of whole buildings through a quick data analysis would certainly be welcome. But, can you extract sufficient information for business decisions regarding the prioritization Energy Conservation Measures (ECMs) in this way, given the idiosyncrasies and well-hidden features of commercial buildings? Answering this question affirmatively by improving the contributing technologies has been a challenge embraced by innovators of all stripes. Here is a list to help you sort the field:

The value of the recommendations output by any of these category of tools is inevitably compared to the recommended ECMs that come from conventional engineering calculation approaches.

The Association of Energy Services Professionals (AESP) recently invited speakers from PG&E, Autodesk and First Fuel among others to address continuous learners on the topic of software analytics tools that attempt to remotely assess whole-building energy performance. This session was captured and is available with slides and audio here. Based on this

information, plus recent conversations with commissioning experts familiar with operational building analytics, here is an overview of how each category is being deployed today and how the categories might evolve to fill out the energy professionals’ toolkit.

Building information modeling (BIM) and advanced simulation approaches like those possible with Autodesk’s Revit are being used for energy assessments and audits, as well as to drive deeper energy retrofits. Autodesk’s Aniruddha Deodhar explained that energy conservation measures recommended by this modeling approach extend into design changes like daylight controls, insulation, window upgrades etc. Such fundamental design changes in the building offer the potential of greater energy savings, than operational (adjust setpoints) or behavioral (encourage occupants to turn off lights when not used, e.g.) ECMs alone. Autodesk’s Rapid Energy Modeling method uses capture options like satellite and aerial images, photos, drawings, laser measuring, plus basic building data gleaned directly from Revit building information models.

Autodesk has been working on ease-of-use of its sophisticated modeling software that evolved to meet the 3D CAD needs of architects, structural engineers, MEP engineers, designers and contractors. In the case of Rapid Energy Modeling, Autodesk’s Deodhar explained that the toolset was designed to be simple enough for a high-school student to use, which is key due to the scarcity of graduated energy engineering talent. He pointed out that the models incorporate the findings of energy savings sensitivity studies for 12 common building types.

Meter/Sensor-Based Remote Building Energy Performance Analytics

First Fuel uses meter data, mapping tools, weather data and occupancy data to model a commercial building’s energy performance. The venture-funded company provides energy auditing services to commercial building owners that are typically packaged and delivered through

utility partners. Utility partners use First Fuel’s cloud-based ‘zero touch’ energy assessment tools for customer engagement and motivation, as well as to enable performance tracking and regulatory measurement and verification.

One PG&E Emerging Technology program offers commercial facilities of greater than 50kW in electric demand the opportunity to find energy savings opportunities using analytics software provided by First Fuel and C3. With the expectation of over 15% post-installation energy savings, participants are offered an upfront incentive and a performance incentive tied directly to achieved savings through implementing the retrofit, as well as operational and behavior efficiency measures suggested by these in-the-cloud tools.

Hierarchical Modeling and AFDD-Based Building Performance Diagnostics

The team at KGS Buildings makes a compelling case for a modeling approach to whole-building energy assessment that also supports a continuous and connected process as you move up and down through a building system hierarchy. Diagnosing a detected anomaly, for example, can require examining operational efficiency of the HVAC system as a whole, then a series of VAV's all connected to one AHU, then an individual AHU or an individual VAV, etc. Sometimes called hierarchical rule-based FDD, or monitoring-based commissioning (MBCx), software suites like KGS Clockworks™ have a Fault Detection and Diagnostics (FDD) knowledge base at the core with decades of accumulated performance data, made accessible with the latest data search methods. They can provide an enterprise view across multiple buildings and multiple building automation system platforms down to individual equipment by comparing data collected from each facility to its library of diagnostic code data. Clockworks' library incorporates cooperative research and development with Pacific Northwest National Laboratory (PNNL) on diagnostics for outdoor air economizers and whole buildings as well as retuning algorithms that identify operational inefficiences leading to comfort and maintenance problems and excess energy consumption. A book on the topic, entitled Automated Diagnostics and Analytics for Buildings, has just been released by authors from PNNL and the University of Florida.

As KGS Partner, Nicholas Gayeski, explains in a recent whitepaper, “A central challenge for Automated FDD is the need to deploy diagnostics across many different building profiles, systems and types of equipment. Effective solutions must avoid re-writing diagnostics with every new building, which is cost prohibitive, while at the same time avoid false positives. Clockworks™ addresses both of these two priorities with a centrally managed code set that is customized to individual facilities through a scalable software configuration architecture that enables rapid deployment. This means that a complete library of diagnostic code can be rapidly applied to individual buildings, entire campuses or even large building portfolios by mapping point, equipment and system parameters directly into an internal online tool that augments the central diagnostic code without re-inventing the wheel. This is referred to as mass-customization."

Caption: Clockworks™ prioritizes the results by energy cost, as well as comfort and maintenance on a 0-10 scale. All results from equipment and system level analyses appear in the punchlist that you see above according to the date range selected. This list can be sorted by portfolio or individual building, as well as equipment class and type of analyses. This allows a user to drill into a specific building, piece of equipment, or type of analysis. The figure above illustrates the results of diagnostics across a portfolio with a daily interval of 24 hours.

Real-Time Operational-Data-Based Building Performance Diagnostics

The Connected Building Commissioning process of Energy Engineering services firm, Altura Associates, exemplifies yet another approach to whole-building/whole-portfolio energy assessment. This involves on-site connection to the building management system (BMS) to extract realtime data from thousands of measured HVAC, water and lighting points and feeding this to the cloud-based SkySpark™ fault detection and analytics platform from SkyFoundry. From this diagnostic scan, a detailed set of building system-specific rules is extracted. This results in a fast and deep understanding of systems performance and the discovery of improvement opportunities.

Altura’s Matt Schwartz is using this Connected Building Commissioning process for client Pacific Medical Buildings (PMB) of Southern California. Early program results have delivered energy cost savings of over 20% per building, representing annual cost savings of more than $65,000 across just two buildings.

According to Schwartz, “Analytics is not a box that sits on the wall. You cannot get the job done front-to-back with a hands-off remote approach. By plugging right into the BMS, we’re not working on ‘Big Data,’ as much as working on the ‘Right Data’. Our mix of onsite engagement plus cloud analytics includes meeting with staff and tenants so we understand the ‘people’ component. With this combination, we’ve been able to knock these assessments out building-by-building, at an investment on the part of our client that is relatively low, while returns are high.

Caption: Before and After Supply Air Temperature Control. Note the significant cycling of supply air temperature from the unit before the changes. As a result of the improvements, occupant comfort is greatly improved and the lifetime of compressors is extended.

The CBCx process has allowed the team to uncover issues which might otherwise have gone unnoticed, or been deemed too time consuming to troubleshoot. The SkySpark visualizations above reveal how a rooftop HVAC system for one of the facilities was experiencing a high frequency of cycling due to poor system tuning and control. With a relatively simple fix (new control logic and tuning parameters), the system was tuned and tested to decrease the cycling frequency. As a result, the equipment is now at a much lower risk of failure, comfort control is improved, and operational costs were significantly reduced.

Conclusion

[an error occurred while processing this directive] There are many other companies entering the fray when it comes to software for quickly finding the best opportunities for operational savings across a whole building or portfolio - and, finding worthwhile design upgrades like building envelope or lighting changes. Questions to ask when reviewing offerings include:

Then don’t spend too much time analyzing before diving in because, by tomorrow, each of these categories will have evolved and merged in ways we haven’t thought of yet.

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