The concepts of green building and sustainability are very popular right now in construction and elsewhere, but they go beyond installing new windows or smart thermostats. According to Nora Knox from the US Green Building Council, this process “applies to buildings, their sites, their interiors, their operations, and the communities in which they are situated.” It is a holistic construction approach that provides a number of benefits in addition to being “good for the environment.”
Indeed, green building has taken hold in the US construction industry and shows no signs of disappearing anytime soon. On the contrary, the practice is evolving quickly and the innovations taking place every day promise to make it even more attractive to consumers of all stripes.
A key tenet of green building is to minimize the effect construction has on the surrounding environment. It’s about more than curtailing emissions on the jobsite and also includes the use of recycled/reclaimed components, locally sourced raw materials (cutting down on transport, gasoline, and vehicle exhaust), products with long lifespans, and goods with reduced or eliminated toxic ingredients. The focus goes beyond the construction process.
Instead, the impacts a product has on the environment are measured from the “cradle to the grave” and encompass the five main stages in the lifecycle of a product: raw material acquisition, manufacturing, distribution, use, and end-of-life management. Taking all of those stages into account enables the consumer to make informed decisions regarding the resources they will and won’t use.
The idea that an office facility or home could consume no outside energy whatsoever has become a reality because of numerous advances in the construction industry and the introduction of new green building products and techniques. One way this is possible is because net-zero energy buildings (NZEBs) are becoming their own power plants and producing just as much energy (if not more) as they consume.
In fact, the American headquarters of German software company SAP is one such NZEB that is certified LEED Platinum and incorporates a green roof, rainwater collection systems, and geothermal energy. It’s rather simple for an international software producer to make the significant investment in constructing an NZEB because the long-term gains in lowered energy costs will offset the initial outlay, but for the average homeowner, using green building techniques has historically been far too expensive.
Changes are slowly taking place that will make green building feasible for more residential structures. Penn State University’s GridSTAR Center is currently working on the development of a net-zero house that will be affordable for the majority of homeowners. The folks at GridSTAR Center are implementing a couple of key solutions that may make this all possible.
One is to use photovoltaic roof shingles along with a solar thermal collector to help provide hot water and space heat. The other critical element is the 10-kW battery recycled from old Chevy Volts used both as a backup power source as well as an electrical energy repository that can “level the load” by storing electricity and deploying it to the grid at large. While this project is still in progress, these are exciting steps forward and may lead to further innovations in the near future.
The EPA reports that US citizens spend 90% of their time indoors on average. Individuals who occupy green buildings are exposed to lower levels of indoor pollutants and enjoy greater satisfaction with air quality and lighting. The benefits of green building are even more pronounced in the workplace. Carnegie Mellon University research has shown a 2% to 16% increase in worker and student productivity while a similar study published in the American Journal of Public Health found that improved indoor environmental quality contributed to substantial reductions in perceived absenteeism and work hours affected by asthma, respiratory allergies, depression, and stress.
One thing that makes green building difficult for homeowners to afford is the fact that the building becomes self-contained to a point that the amount of additions needed make the cost incredibly prohibitive for the average person or family. This problem may be solved by the advent of net-zero communities. Taking the sustainability effort from the individual home and transferring it to the community level opens up other avenues for renewable energy and economies of scale in technology procurement and implementation. For instance, most net-zero homes utilize solar or wind power on site, whereas at the community level energy production can incorporate cogeneration plants running on biomass or geothermal power, trigeneration plants that combine cooling, heat, and power, and larger-scale solar options that can be built on nearby sites as part of a planned development.
At the forefront of this movement is the US Army, which has begun eight net-zero community projects at installations around the country including Ft. Bliss in Texas. Ft. Bliss is home to 90K residents and occupies more than 1M acres of land, making it a great proving ground for a number of techniques and inventions such as waste-to-energy power generation, geothermal plants, and large-scale solar photovoltaics. By 2020, Ft. Bliss is expected to be completely self-sufficient as a net-zero community and, if successful, may usher in a new wave of similar initiatives across the US.
With each promising development and new innovation, green building takes another step forward and comes closer to becoming more cost-effective. Once it reaches the level of affordability that will make it accessible for all, green building will become the standard construction process, rather than a unique methodology.