The Complicated Undertaking of Net-Zero Construction

Net-zero construction requires structures to produce as much energy as they consume to lower their carbon footprint. Buildings that emit fewer greenhouse gases (GHGs) are ultimately better for the environment. However, this process doesn't come without challenges. 

1. Ensuring Consistent Renewable Energy

Net-zero construction means you produce power for your building. While you can connect to municipal energy, you must match it with renewable sources. For example, photovoltaic (PV) panels have become prominent across net-zero structures because they harness the sun's rays for electricity. Solar power can be adequate, but you must ensure consistency when powering large buildings. 

Intermittency can be an issue for some locations, considering cloud cover and the night sky. Architects must optimize their buildings to harness as much sunlight as possible to maintain their net-zero status. Energy-dense batteries are a strategic way to hold power when sunshine is lacking. Some experts recommend using wind and solar power as complementary pieces, thus ensuring steady power. 

"Combining wind and solar smooths the power supply compared with using wind or solar alone," said Mark Z. Jacobson, a Stanford University professor. "Similarly, combining wind or solar energy from distant facilities can average over productivity lulls in particular locations."

2. Optimizing HVAC Use

Building a net-zero structure means optimizing the systems that use the most energy. Your typical house or office allocates much of its power consumption to the HVAC, especially in the summer and winter. This heating and cooling mechanism is also a vital sustainability component because of its emissions. HVAC systems emit carbon monoxide (CO), carbon dioxide (CO2) and other harmful pollutants. 

Modern HVACs have become more efficient, starting with the equipment used. Check the seasonal energy efficiency ratio (SEER) to see how efficiently it can heat and cool a home. Calculating the SEER for an air conditioner includes dividing heat removed by the energy requirements in watt-hours. Optimizing HVAC use also entails smart technology, as these devices adjust their output based on occupancy and sensors. 

3. Minimizing Energy Loss

While producing energy is critical to net-zero buildings, construction crews must also focus on energy loss. Doors, windows and other building components can let cool and warm air escape. The Department of Energy (DOE) says windows are responsible for 30% of heat loss, leading to higher energy use in the winter. Architects and designers must minimize these losses to reduce their power consumption year-round. 

One way to mitigate energy loss is with storm windows, considering they reduce leaks and better control the temperature. The DOE also recommends low-e coating and glazing to enhance thermal performance in your building. Insulation is another worthwhile approach to minimize energy loss, as this material reduces thermal flow. Some net-zero buildings use fiberglass insulation because of its high R-value and non-combustibility.   

4. Managing the Costs of Sustainability

Sustainability headlines the future of construction, as experts say its $476 billion value will grow by 9.64% until 2033. However, the costs can inhibit the creation of net-zero buildings. Some technologies are newer and have higher upfront costs, thus increasing the necessary capital for each project. For example, energy-efficient windows are typically more expensive because they have more panes and are in high demand. 

Proper cost management starts with your life cycle cost analysis (LCCA). This examination tells you the upfront and maintenance costs, thus outlining the long-term savings. Architects and interior designers must also consider the financial incentives through tax credits. Suppose you build a multifamily housing complex with energy-efficient features. You can get a rebate between $2,500 and $5,000 for achieving Energy Star certification. 

5. Ensuring a Comprehensive Green Process

A holistic approach toward green construction means emphasizing renewable energy wherever possible. Consider the vehicles you use on the building site. Leveraging eco-friendly equipment reduces your carbon footprint by limiting fossil fuel consumption and controlling emissions. 

Equipment manufacturers make electric and hybrid models for jackhammers and other hand tools. These options reduce emissions and are more environmentally friendly to your building site. Another wise selection is eco-friendly fuels like biodiesel. Some equipment uses a 20% biodiesel and 80% diesel mix to reduce their ecological footprint.
Even during the design process, before construction even begins, a sustainable sampling process can make a positive difference.

Examples of Net-Zero Construction

Net-zero construction is becoming more prominent worldwide as building owners incorporate sustainable policies. One of the best examples takes you across the globe to the National University of Singapore. This educational institution has a net-zero building in the School of Design and Environment, boasting solar panels and plentiful shade from the rooftops. The university recently touted record solar power from its tandem cells. 

"Remarkably, after 15 years of ongoing research in the field of perovskite-based solar cells, this work constitutes the first experimental evidence for the inclusion of cyanate into perovskites to boost the stability of its structure and improve power conversion efficiency," said Hou Yi, assistant professor at the National University of Singapore. 

Another stellar example of net-zero is the Bullitt Center in Seattle, Washington. This large office building has 575 solar panels that produce energy and sell it back to local utility companies. Seattle's climate brings constant rainfall in the fall and winter, so the Bullitt Center optimizes its energy harnessing in the summer. Other net-zero features include a regenerative elevator and radiant heating.

Lastly, we look at Silver Spring, Maryland. A few years ago, this town introduced the Unisphere as one of the world's largest net-zero buildings. This project is relatively new, opening its doors in 2019. The Unisphere is 210,000 square feet and is a powerhouse through its renewable energy technologies. In just nine months, it generated over 237,000 kilowatt hours (kWh) of power for the grid.