By Warren Evans
Zero energy (ZE) commercial buildings are grid-integrated buildings capable of generating as much energy as they consume through advanced efficiency technologies and onsite generation systems such as solar power and geothermal energy.
Beyond the environmental benefits, ZE projects provide owners with significant business value through resilience, employee and tenant retention and the ability to enjoy higher rents. Through intelligent design, clean construction and well-planned financing, developers can substantially increase the value of a commercial building with ZE.
ZE buildings reduce overall energy use to achieve ZE status, initially through high levels of energy efficiency and conservation measures, and then by using onsite renewable energy generation (or offsite as in community solar). Building designs can also be delivered across an energy performance spectrum, starting at required building code standards, (negative energy), moving through ZE, all the way up to advanced designs, (positive energy).
What are the benefits of ZE?
Buildings in the U.S. account for up to 40 percent of greenhouse gases (GHG) emissions, therefore a significant effort is needed to reduce these emissions both for health and safety reasons and to meet the NY Reforming the Energy Vision (REV) goals of 50 percent renewable energy by 2030 and 40 percent reduction in the GHG emissions from 1990 levels.
To help achieve these goals building codes are steadily moving toward ZE supported by tax and other economic incentives that accrue to developers and builders who use ZE designs.
ZE Building Construction Benefits include: increased building value (rent, marketing, sale); increased comfort’; decreased carbon footprint’ and decreased overall costs (utility, maintenance).
As a result, according to the Rocky Mountain Institute (premier energy research organization) data shows that ZE buildings can provide strong economic returns to developers and landlords, 3 to 7 percent higher occupancy rates, 3.5 percent higher rental rates and 13 percent higher sales prices.
The value of ZE amounts to a 30-50 percent energy and cost reduction savings over the course of a building’s useable lifetime. In a word, the value of zero is huge.
In fact, some private commercial property owners have proposed or constructed buildings designed to be ZE to meet their corporate goals. Local examples include Dave Bruns’ two Net Zero village projects in Schenectady and Overlook Ridge’s commercial enterprises and net zero townhouses in Little Falls.
How to implement ZE.
Achieving commercial ZE objectives requires a combination of best practice energy efficiency measures and renewable energy production and is surprisingly achievable. Working under an “integrated design process”, (bringing different specialties together to produce sustainable designs), the first steps require establishing an efficiency goal and cost budget.
Next, the design team will develop the most efficient building “envelope” by employing energy-efficient technologies such as lighting, HVAC and controls, as well as ZE compatible construction materials, reduced plug loads and proper siting of the building to take advantage of passive heating and cooling.
Achieving a reduced energy consumption design then makes it possible to meet the building’s energy needs with the appropriate renewable energy source(s).
Finally, educating occupants and tenants to ensure they understand how to comfortably maintain low energy use is a strategically important feature of achieving the return on investment for the overall ZE design.
How much does ZE cost?
Green buildings with passive heating, cooling and ventilation use less energy therefore cost less to heat, cool and operate. The capacity to tap into renewables makes buildings more resilient (heat up and cool down slower), safer and more comfortable for their occupants during power outages and extreme weather events. Some insurance companies even offer discounted insurance premiums, for buildings meeting the proper certified energy efficiency criteria.
There are numerous examples of commercial buildings achieving ZE or near ZE with little or no added project cost. Some studies show that the incremental design and construction cost of ZE buildings is between 3 to 5 percent over conventional construction, those costs do not consider the benefit of 30-50 percent life-cycle cost savings from the lower energy costs of operating the ZE building over time. This benefit is what makes the long-term return on investment and overall savings of ZE buildings worthwhile.
The future of ZE.
The ZE genie is out of the bottle, there’s no turning back. States, municipalities and local governments are responding to regulatory mandates by moving required building codes towards ZE targets.