City’s First Self-Powered Building Unveiled: How Does It Work?

Located at the corner of Hamilton Avenue and West 9th Street at the edge of Carroll Gardens in Brooklyn, the Delta is built in a triangular shape to optimize its energy generation efficiency. Photo courtesy of Voltaic Solaire.

You might think that once you install a rooftop solar power system, it directly provides for your home’s energy needs, such as lighting and air-conditioning, leaving you independent of “the grid.” That’s what this reporter thought until visiting the so-called “first self-powered building” in New York City, a new five-story building in Carroll Gardens, Brooklyn, on the dark and stormy afternoon of July 18.

The Delta is a private building designed and constructed by a Brooklyn-based alternative energy company, Voltaic Solaire, to embody a greener living philosophy. In order to realize their “100 percent self-sustainable” goal, engineers and architects installed solar awnings, a solar thermal system and a vertical axis wind turbine atop and on the surface of the modern dwelling.

Its architecture and corner location is also important in terms of optimizing power generation efficiency. Originally oriented northeast-southwest, it wasn’t ideal for the building’s “solar skin” to absorb the most of sunlight. The developers repositioned the property into a triangular shape, facing directly to the south, and equipped it with insulated pipes and energy-efficient windows and appliances to conserve the power the system generates as effective as possible.

“We wanted to build a building with all the parts running efficiently to conserve and produce energy,” said architect and designer Rolzes Diaz, who was responsible for the project’s photovoltaic solar panels and architecture design.

Click Image for Slideshow of “The Delta”

So, how does a solar-wind power system actually work when it comes to powering your home? It turns out it has a give-and-take relationship with the electric grid system.

During the day, solar panels and wind turbines transform sunlight and wind into electricity, and send it straight back to the power grid, contributing to the whole area’s grid system as a small independent power plant. The green energy of the solar-wind power system thereby reduces dependence on electricity produced by oil and nuclear power.

At night, when tenants of the solar-wind powered home turn on the lights, the electricity is supplied directly through the power grid, coming from large energy suppliers. That daytime energy produced by the solar or wind system has already been consumed somewhere else on the grid — it can’t be stored for later usage.

So if the electricity a self-sustainable building receives still comes from the grid, how does a solar or wind power system save an owner money? Well, here is the answer.

Rolzes Diaz, left, and Mark Robinson, right, of Voltaic Solaire played the leading roles in "The Delta" development. MetroFocus/Menglin Huang.

“A house with a solar installation is actually selling the electricity back to the utility and back to the city’s electrical supply,” said Diaz, explaining that the power it generates is paid for by the city’s energy suppliers.

In order to track how much the particular building has produced and consumed, a computer-like, two-way “net meter” is used to calculate the result.  At the end of a month, the net meter shows the electrical production versus consumption, just like a balance sheet. In that case, if the production surpasses the consumption, the owner of the system will receive a check from the energy supplier; otherwise, the electricity bill will still be smaller than normal.

With highly efficient equipment and appropriate design, the Delta is estimated to be able to produce 18,000 to 20,000 kilowatt hours of energy throughout a year, far more than the 2,700-square-foot property needs, which makes it completely “self-powered.”

The building, which cost roughly $700,000 to build, is now fully furnished with a studio on the second floor and a triplex on the top three floors. It will be rented as a bed-and-breakfast for people who are interested in renewable energy, according to the developer, starting next month.

Inspired by Mayor Michael Bloomberg’s PlaNYC plan, which is committed to bringing the city’s carbon footprint down by 30 percent by 2030, engineers and designers at Voltaic Solaire are dedicated to making eco-friendly buildings in New York City. In addition to the Delta, the company has also started the city’s first solar-powered brownstone in Park Slope, which is expected to be completed next year.

These projects were initiated to not only change the way energy is produced, but also inform New Yorkers of a greener lifestyle, said Mark Robinson, the chief operating officer at Voltaic Solaire. “We also educate and re-educate our electricians, plumbers and carpenters as to why we are doing something different from what they’ve known for years and years.”

For the past few years, New York City has been a leader among cities encouraging the use of sustainable energy and green buildings.

Earlier this year, the City Council approved a package of green zoning changes that will make it easier for property owners to make energy efficiency upgrades and even produce their own wind and solar power. Developers will also be given more freedom to incorporate eco-friendly elements into their building designs.

Since 2010, the New York City Solar America City Partnership has designated five Solar Empowerment Zones across Brooklyn, Manhattan and Staten Island, where installing rooftop solar energy systems is deemed most beneficial to local residents and the city’s electricity distribution system. The City University of New York’s interactive solar map displays real-time solar energy production citywide, allowing users to estimate the costs, incentives, and payback period for investing in solar.

“We have a society that has become incredibly wasteful,” said Robinson. “And we are now responsible for it.”