Net Zero Energy Design Challenges & Innovations

Zeroing in on energy: Planned buildings expected to make as much energy, or more, than they burn

The Post and Courier, September 3, 2017

Every hour, the sun beams more energy onto Earth than it needs to satisfy global energy requirements for an entire year, according to National Geographic and other sources.

Of course, harnessing and storing solar energy as a primary source of power remains an engineering challenge. Yet enough technology is available now that cities and countries around the nation and globe are proving that they can power themselves on 100 percent “renewable energy” and others are pledging to do so within the next 10 to 20 years.

With South Carolina having well over 200 sunny days a year, the future could be very bright if the commitments pan out.

Meanwhile, efforts to make individual buildings “net zero” are emerging in the Palmetto State.

Net Zero Energy Buildings, or NZEG, are constructed to make as much, or more, energy than they use by combining efficient building systems, methods and materials with solar and wind energy systems.

Examples include Half-Moon Outfitters, which is embarking on a net zero renovation of a 14,000-square-foot building in the midtown district of Greenville.

Daniel Island-based Insulsteel of South Carolina has built 20 net zero homes using its EcoShell system in the Charleston area, has 10 more in the works and plans to expand across the state and region.

“We design our homes to meet net zero standards,” says Steve Bostic of Insulsteel.

As the state fumbles around halted nuclear power plant projects and the world grapples with climate change, making buildings be their own-power plants could be a solution for the future. The concept excites people such as Sustainability Institute Executive Director Bryan Cordell.

“We have reached a time where this is not only possible, but necessary, if we are going to dramatically reduce carbon emissions and take serious steps to address climate change in our cities,” says Cordell.

One net zero project that may serve the most visible in the Lowcountry is in the works for King Street, between Line Street and the I-26 overpass at the Septima P. Clark Parkway, also known as the Crosstown.

Modern + solar

Developer Richards Gregory has combined his passions for contemporary architecture and environmental stewardship for an 8,300-square-foot, four-story office building at 663 King St.

Through energy-efficient building materials, methods and equipment and solar panels, Gregory says the building has been engineered to make at least as much energy as it uses.

Gregory already has achieved that by renovating a house structure into an office at 68 Line St., which is on part of the three-quarter acre property.

Largely because of its contemporary design, it took a few years for Richards and architect Tara Romano to get approval from the Charleston Board of Architectural Review, which happened on Aug. 9.

Both Gregory and Romano think the location of the building helped make the contemporary design more compatible with the BAR and the public.

Romano says, “With this building being adjacent to an overpass, and with few historic structures immediately surrounding it, we encountered less push-back from the public than we might have had if this building were in a different location in the city. “

Gregory says he expects to get the building permits secured by the end of the year and that construction will take between 12 and 18 months. He feels confident that it will be open by the middle of 2019.

Design challenges

During the architectural review, Romano says the design evolved from its initial concept of shifting floors and undulating curves to a design with a large gentle curve along its south wall and a front wall that hinges off of a point, each floor pivoting back as it rises.

“These features respond to the context and angled grid of its site, while together forming a composition that retains the proportions that you see in typical Charleston structures,” says Romano. “The storefront opens up and engages with the sidewalk with large expanses of glass, a canopy and a cylindrical-shaped entry, while the north wall along the interstate waves out and wraps the corner in a gradient of colored louvers and stairs.”

Due to the high visibility of the building, Romano adds that “great care was taken in the design of each view of the building.”

“There are plenty of products and systems out there these days, but finding ones that are able to meet the (sustainability) criteria while achieving the desired exterior look of the building has been challenging,” he says. “It has involved a fair amount of research and coordination with the project engineers and manufacturers, and there is only so much space to work with when dealing with the constraints of an urban environment.”

Romano and Gregory say that the Sustainability Institute, along with project engineers, the contractor and solar consultants, played a key role in helping create the project plan.

RISES pilot

The Sustainability Institute’s Cordell calls Gregory’s project “exceptional and pivotal for our region” in both design and sustainability. It also serves a pilot for the institute’s new Charleston RISES high-performance building certification program.

“RISES certification promotes and recognizes new construction projects that are at least 30 percent more energy- and water-efficient than projects that are simply code compliant, and projects that are constructed using materials and products that do not adversely affect the health and well-being of building occupants,” says Cordell.

“The certification requires thoughtful design choices around site planning, energy efficiency and renewable power, water conservation, sustainable materials, and healthy interior choices, as well as awards credits for innovative approaches.”

Cordell adds that as Gregory’s project undergoes construction, the institute will provide on-site quality assurance and verification.

Despite the fact that Gregory’s building will be expensive, which Gregory says has more to do with the contemporary design than sustainability elements, Cordell sees replication of net zero elements as “absolutely do-able in other parts of Charleston and for building of all types and sizes.”

“The Charleston RISES certification program is designed to help project teams streamline thoughtful choices and achieve sustainability goals in an affordable and easy way.”

Half-moon rising

While Gregory’s building will start from scratch, Half-Moon Outfitters is taking an existing building in Greenville and doing everything possible to make it net zero.

The building at 603 East Stone Ave. was originally constructed as an auto parts store, and was ideally suited for solar because of its flat, new roof and “great Southern exposure,” according to Half-Moon Owner Beezer Molten.

Like Half-Moon’s distribution center in North Charleston, Molten says they will follow standards established for LEED (Leadership in Energy and Environmental Design) Platinum certification and go a “step further” with an NZEB (Net Zero Energy Building) designation.

“The whole roof is covered in solar,” says Molten, noting that the 58.1 kilowatt system should cover energy expenditures estimated at 47 to 60 kilowatts.

Molten says the 10,000-square-foot portion that will be Half Moon’s store will “definitely be net zero,” but the energy use of two possible tenants he is negotiating with for the remaining 4,000-square-foot space is unknown.

Molten notes that since gaining LEED Platinum certification in 2005, solar energy has become more viable for two reasons: Expertise has increased and costs have decreased. He sees many benefits to Half-Moon renovating an environmentally sound store.

“This is something that we can do and something that resonates with both customers and employees,” says Molten, noting that after the LEED Platinum certification of North Charleston building, he found the quality of job applicants increased.

Molten expects the monetary “payoff” of the solar panels by energy savings to be 48 to 60 months.

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