In our San Francisco office, Pranathi Bhattacharji, has been published by the Institute of Electrical and Electronics Engineers (IEEE) for her masters research article titled“Reduced Order WECC Modeling For Frequency Response and Energy Storage Integration”. The published paper was presented at the annual meeting in Utah this past July.
To read the article click here.
Posted in Awards, Staff Insights
Tom Bevans, PE, LEED AP – San Francisco
Ryan Braun, PE, CxA – San Diego
Posted in Staff Insights
By: Calina Ferraro, P.E., CxA, CPD, LEED AP
It has been over a year since the new 2013 Title 24, Part 6 Energy Code (or just “Title 24”) went into effect on July 1, 2014. This new Code edition brought with it a number of new design requirements that owners and their design/construction teams need to understand in order to avoid unexpected surprises. This article outlines some key newly required design elements.
There is a new requirement that buildings be “solar ready” (Section 110.10), which affects all disciplines. The solar ready requirement applies to new construction only, for projects that are:
To meet the solar ready requirements, projects must include a designated Solar Zone on the roof or adjacent structure. There are a number of specific requirements for this zone in the Code section defining size, shape, etc., but generally it must have a southern orientation and be free of obstructions. The Solar Zone must be designed structurally to accommodate future solar panels; electrical conduit pathways must be included to a location suitable for a future inverter and meter; and a plumbing pathway must be shown for piping to a location for future solar water heaters.
Traditionally, Title 24 requirements applied primarily to the building envelope and general base building systems; they excluded “process loads” associated with specific functions of the building. A number of these systems have now been brought in as “covered processes” with new Code requirements. These new covered processes include:
The new Code has quite literally rewritten the book on what is required for electrical and lighting systems, with a strong focus on controls and metering.
The requirement for multi-level lighting controls(i.e. dimming) effectively pushes lighting design to use LED fixtures (Section 130.1(c)). Requirements for local on/off controls, automatic response to occupancy, daylighting, and demand response have increased the complexity for sensors, circuiting and controls for both indoor and outdoor lighting systems (Sections 130.1(a),(c),(d) & (e); 130.2).
New controls for receptacles and plug loads are also required. For example, controlled receptacles (e.g. circuited to a wall switch) must be located within 6’ of any uncontrolled receptacle (Section 130.5(d)). This adds a significant amount of wiring (add therefore construction cost) to electrical systems.
Finally, depending on the project scope and size, electrical meters for the building occupants (different from the utility meter) are required. These meters need to track historical data per period and sub-meter different end-uses (e.g. lighting, HVAC, plug load, etc.) (Section 130.5 (a) & (b)).
The changes outlined above represent brand new requirements to the Code. In addition to these, a number of the previous Code requirements have been expanded or made more stringent. Minimum allowable equipment efficiencies have been improved and there are a number of new control requirements with a focus on occupancy, demand shedding and demand-control ventilation.
By improving the baseline, the new Code makes performance compliance approaches (i.e. using an energy model to show compliance) more difficult, increasing modeling time and cost. In some cases, it may also decrease incentive funding from programs such as Savings by Design by narrowing the percent improvement of the proposed building over this new and better baseline.
It is important that owners and design teams be aware of these new required design elements and incorporate them early in the design process to coordinate additional space and equipment requirements, and account for additional project costs. An educated design team with a clear understanding of the Code requirements is the best way to mitigate the impact on new projects and avoid delays in permitting.
In addition to these new required design elements, our next article will look at the new Code requirements for the design and construction process, including design review, commissioning and specific testing.
In addition to more stringent design requirements discussed in the previous article, the new Title 24 has added requirements to the design and construction process, in particular: Design review, commissioning, and acceptance testing.
The purpose of a design review is to verify that proposed design elements meet current Code, and that best practices are considered. A formal design review is required for all new projects (Section 120.8), but the process varies based on project size.
Regardless of the reviewer, the design review process requires:
All three steps have Title 24 compliance forms that must be completed and submitted to the building department along with the permit submittal.
For new projects and core and shell fit-outs, commissioning is required on projects larger than 10,000ft2 (Section 120.8). There are elements of the commissioning process at every stage of design and construction. In design, the commissioning authority oversees the documentation of the Owner’s Project Requirements (OPR) and Basis of Design (BOD). They also develop a commissioning plan to be implemented in construction. This commissioning plan must be incorporated into the construction documents that are submitted for a building permit. The OPR and BOD are not required to be submitted to the building department, but may be requested by the plan reviewer.
During construction, the commissioning authority oversees the implementation of the commissioning plan, including functional performance testing, airflow test & balance, point-to-point calibration of controls, operator training, development of the systems manuals, etc. A summary of these elements are consolidated into the final commissioning report. The final commissioning report may be requested by the building inspector prior to granting occupancy.
The detailed requirements of the commissioning process for each project are left to the commissioning authority or design team to specify. It is not required that a separate commissioning authority be brought onto the team; however, commissioning is often outside of the basic services offered by design professionals. From experience, projects see the maximum benefit when an independent third party commissioning authority is brought onto the team to lead and manage the commissioning process.
Acceptance testing and the associated forms are not new to this Code edition; previous codes required contractors to perform acceptance tests and submit documentation. In the 2013 Title 24 edition, however, acceptance tests for mechanical* and lighting controls must now be performed by Certified Acceptance Test Technicians (Section 120.5(b) & 130.4(c)). These are independent technicians with specific training and certification from the Energy Commission to validate system controls.
*There is currently an exception for the mechanical controls testing due to an insufficient number of certified test technicians available; these are still performed by the mechanical or controls contractor.
In summary, the 2013 Title 24 Energy Code added new design elements that must be addressed by the design team and therefore potentially expand the number of professionals required. These new team members should be integrated early on to avoid delays, and to achieve the maximum project benefit from these required processes.Posted in Clean Energy, Project Insights