In this stage, the HP Manager helps the owner understand the retrofit opportunities given the project resources and objectives, such as energy/water efficiency, budget, time schedule, site conditions, regulatory requirements and more. If applicable, an architect or general contractor may be hired on to weigh in on design and costing. With holistic building performance in mind, innovative solutions beyond lighting upgrades and HVAC controls must be considered, such as passive ventilation, thermal massing, radiant hydronic cooling, etc. Taking an efficiency-first approach, incorporating passive design strategies before technologies that require capital outlay will significantly reduce first costs while meeting ambitious performance goals. Figure 2 depicts the various elements that combine to help a retrofit achieve net-zero energy.Each retrofit opportunity is then analyzed through base building audits, utility analysis and sophisticated energy modeling.
The HP Manager helps the owner and stakeholders clearly define project objectives, performance goals and retrofit strategies to meet those goals. Through facilitating iterative, multi-disciplinary charrettes, support is gained on various retrofit strategies before moving into the design phase.
PART II: Design
Upon defining objectives and understanding the opportunities for retrofit strategies, the project team is ready to move into design. In this phase, the HP Manager conducts Life Cycle Cost Analyses on each proposed retrofit strategy to determine financial metrics including the net present value (NPV), internal rate of return (IRR) and net operating income (NOI). These metrics help inform how each retrofit opportunity will meet the OPR and budgetary goals from a first-cost versus life-time cost perspective. Further modeling determines how opportunities can be bundled into synergistic packages of load-reduction retrofit strategies that the ownership team chooses for implementation.
Once the retrofit strategy package is determined, the HP Manager develops a fully vetted Basis of Design (BOD) for the contracted Architect/Engineer/Contractor (AEC) team to develop drawings and design documentation. The HP Manager then oversees
project scheduling and team procurement, reviewing specs for accuracy against design assisting subcontractors with communication and implementation. This approach is fundamentally consistent with Engineer/Procure/Construct methods used to save time and money while ensuring quality.
During design, the HP Manager also begins developing commissioning and Measurement & Verification (M&V) plans to ensure quality implementation of retrofit strategies. By planning these processes early, HPM bridges the gap that all too often presents itself between the design and actual operations of a building. Concurrently, the OPR is updated to include the specific decisions made during the design phase.
PART III: Construction Administration
In the Construction Administration phase, the HP Manager provides turnkey implementation services, overseeing the various subcontractors to ensure compliance with the OPR and optimization strategy. A comprehensive Quality Assurance/Commissioning plan is implemented, which is imperative to ensure that building systems are installed and balanced to meet the performance goals set forth in the design. Through commissioning, the building operator will also receive operations and maintenance training to understand how the building should run at optimal levels. In this stage, the M&V plan is further reviewed and vetted for smooth implementation upon retrofit completion and the operations phase.
PART IV: Operations
Designing and constructing a high-performance building is no easy feat, but the true challenge—and reward—lies in operations. Without verifying and tuning the building’s performance, all of the work put into the design and construction can easily go down the drain. Additionally, it is imperative for the building tenants to understand the requirements for operating at desired performance levels. This is where the vetted M&V plan comes into action, ensuring that monitoring systems and feedback mechanisms are in place and the financial impacts of retrofits can be measured. Several strategies may be implemented to ensure the performance goals are met and maintained, including but not limited to:
- Install sub-metering equipment in units that are not already metered.
- Provide a monthly review for the first year of energy end uses and utility data to continuously monitor and tune building systems.
- Provide tenants with training and incentives for energy and water conservation.
Performance = Value
When considering a building retrofit, performance should always be a central consideration for the benefits it brings to the ongoing operations and occupant wellbeing. In addition to reducing the load and therefore increasing the lifetime of mechanical systems, buildings with better access to natural ventilation and daylight have been shown to improve worker productivity and reduce absenteeism. Depicted in Figure 3, the Washington, D.C.-based U.S. Department of Energy has a goal of complete market adoption of NZE buildings by 2025 and states, such as California, also support the net-zero energy movement. Implementing an HPM approach to retrofits can ensure the achievement of high-performance goals while adding value to real-estate assets.