Battling the complexity of designing government facilities: Sustainable buildings/energy efficiency
The government can be a tough customer, and the projects that state, municipal, federal, and military entities approach engineers about are highly complex. Here, engineers with experience tackling such tall orders offer advice regarding sustainable buildings/energy efficiency.
Mohamed Abdelmoneim, PE, Peng, LEED AP BD+C, Senior Electrical Engineer, EYP, Washington, D.C.
Raymond Krick III, PE, LEED AP, Project Manager, RMF Engineering, Baltimore
Allen Poppe, PE, MBA, Principal Mechanical Engineer, Mechanical & Chemical Group, Manager, Stanley Consultants, Muscatine, Iowa
Rick H. Troberman Jr., PE, LEED AP, CBCP, Mechanical Engineer, EEA Consulting Engineers, Austin, Texas Lindsay
Zanders, PE, PMP, Sr. Project Manager/Director of Projects, Primera Engineers Ltd., Chicago
CSE: Energy efficiency and sustainability are often requests from building owners. What net zero energy and/or high-performance systems have you recently specified on government, state, municipal, federal, and military facilities (either an existing building or new construction)?
Zanders: New construction typically has an increased ability to apply power generation and energy efficient design. Applying power generation, such as photovoltaic (PV) cell placement, is limited by existing structures and available space (typically roof). Likewise, energy-efficient design starts with the envelope, and most renovations focus on the interior only. We recently worked with the city of Chicago to build a new public library and a new fire station on a shared block of property. The buildings had opposite HVAC demands (the library was cooling-driven while the fire station was heating-driven), and were able to capitalize on a shared geothermal well field located in a mutual parking lot between the buildings. Land in Chicago is at a premium, so the geothermal well field had vertical piping reaching depths greater than 500 ft. Although the municipality was the common owner, the different agencies needed to find agreement among the shared infrastructure.
Poppe: Our designs have included DOAS, VRF systems, water-source heat pumps, magnetic bearing chillers, and chilled beams.
CSE: Many aspects of sustainability (power, HVAC, etc.) require the building facility team to follow certain practices to be effective. What can an engineer do to help increase the chance of success in this area?
Troberman: We are often the prime consultant to the owner as an MEP engineer. In these circumstances, we have more control over getting the stakeholders together early in design. If you can get buy-in by the facilities group for different systems being specified, there is a higher chance of the systems working the way they were designed. If the engineer is acting as a subconsultant, it is still a good practice to encourage the prime to include the facilities group in the discussions early on.
Krick: Sustainability is not a bolt-on item, so to be successful in this area the entire team must be on board from the beginning of the project. To allow for proper selection of all MEP systems, thorough coordination must occur. I would also recommend doing a full review of the applicable energy-savings codes or standards with each project, as some of the requirements listed in the fine print often get lost in the shuffle.
CSE: What types of renewable or alternative energy systems have you recently specified to provide power for such projects? This may include photovoltaics, wind turbines, etc. Describe the challenges and solutions.
Poppe: UFC 1-200-02 includes a requirement for domestic hot-water solar heating. We have implemented these systems for military facilities in Texas, Hawaii, and Japan. These systems are a good solution for barracks with high service-water heating loads. We have a Department of Energy project under design that includes PV. While these systems are costly, there are significant LEED points available for EA Credit 2 Renewable Energy and EA Credit 1 Optimize Energy Performance.
Zanders: PV systems are more frequently discussed during design. Ignoring the cost of the product, which may be subsidized by various grants or stimulus incentives, the major challenge with applying PV systems in new construction and renovation projects is the open, available space. In urban environments, PV systems are typically located on the roof. Even with highly efficient buildings, the amount of usable area on the roof can house a PV system capable of supplementing only a fraction of the total building energy use. Wind turbines are another renewable energy source we've explored. These systems are best applied to wide open areas. The challenges presented when applying wind turbines to government buildings is that they are typically located within cities. Adjacent, inconsistent building size, height and length, and mixes of urban green spaces with nearby developments all disrupt the airflow.