While the solar industry continues to grow rapidly in the US and abroad, only a small percentage of non-residential projects include PV installations. However, the potential for commercial, municipal and industrial building construction to incorporate renewable energy systems has never been greater.
To date, the approach has been for the architect /engineer on the design team to provide an allowance for the solar only, with an intent to follow the normal design-build approach using the same perspective, approach and financial model applied to installations on existing buildings.
Well, now is the time to take a fresh look. Engaging the end user and professional design team (architect and engineer) at the concept and schematic design phase can make the PV system a more viable option. Further, this approach maximizes the ability to reduce cost and improve system performance, while speeding up installation completion to better coincide with building completion.
However, buyer beware. While there are MEP engineering firms that do building design well, they may not be solar savvy. Conversely, there are some engineering firms that are solar focused, but not well versed in building industry projects. The good news is that there are now a few select firms emerging in the engineering field that have advanced tremendously on projects involving solar installations, and are more than capable of handling projects in direct coordination with architectural firms.
For example, our firm routinely works with clients to perform all the PV design, engineering and associated tasks from project concept phase. In fact, KMB has completed over 250 solar projects and 235MW nationwide, many of which are full service. The scope of our capabilities includes land surveys; rooftop surveys; shading analysis, PV design; energy production calculations; electrical engineering; structural engineering; civil and
environmental; board hearings; permitting; applications; project management.
By incorporating the PV system at building design phase of new construction, additions or renovations, KMB has proven its ability to optimize PV panel location and minimize obstructions that cause discontinuity and shading. The result is enhanced system performance and significant cost savings – including lower cost per watt ($/W) and greater efficiency (KWH produced per KW installed).
Sadly, the process that would make a PV installation as attractive as possible is rarely followed. However, I believe there will be an industry trend towards incorporating solar from the start of the building design phase because it ultimately minimizes cost, improves aesthetics, coordination, and speed to completion, all while enhancing long term system performance.
Following is an example of recommendations made for the integration at the AE design phase for a rooftop installation:
- Provide a large open and continuous area on the south facing flat rooftops not impacted by adjacent trees, buildings, utility poles, etc.
- Design roof structure to allow for adequate capacity to support a ballasted, tiled racking system.
- Specify a roof type that is most favorable for the PV system installation and performance.
- Do not locate rooftop HVAC units in the area most favorable for PV. Even consider an alternate HVAC design solution.
- Minimize / eliminate rooftop exhaust fans, vent pipes, roof drains, etc. Consider floor plan layouts that help to achieve this goal.
- Design electrical distribution to provide for ease of electrical interconnection, net metering, PV service disconnects and more.
- Provide preferred allowance for the PV inverters such that they are located close to the solar arrays in order to reduce the DC wiring, facilitate installation, and minimize impacts on the surrounding.
- Design routing paths of conduits and wiring – internal and external – to allow for improved aesthetics plus consideration of flexibility for future roof and building modifications.
Steve Schwerd is a partner at KMB Design Group and leads the facilities and energy engineering division as vice president. Steve is a nationally recognized name in the renewable energy field and is a LEED accredited professional.
Contact Steve Schwerd
Email: sschwerd@kmbdg.com
Phone: (732) 280-5623