Green infrastructure is better for the planet. This much we know. But can you really quantify cost savings? In a new report, the NRDC says yes.
In the report, called "The Green Edge: How Commercial Property Investment in Green Infrastructure Creates Value," the Natural Resources Defense Council (NRDC) has come up with an answer to those developers and land owners who cite costs as a reason to not install green infrastructure for stormwater management. The full report is available as a PDF here; and a shorter brief is accessible here.
You may recall that last week, we ran a video blog from EPA policy analyst Abby Hall, who spoke about green infrastructure such as rain gardens, green streets, and so on, and how these investments turn cities into nicer, healthier, and more environmentally friendly places to be. In its report, the NRDC has touched on these elements as well, and quantified the cost savings.
For example, here's how the organization quantifies savings for a medium-sized (53,600 sq. ft.) office building, with a green roof, rain gardens, a 10,000-sq.-ft. permeable pavement parking lot, and 20 planted trees (note: this is based on energy rates in Philadelphia):
Annual energy savings: $1,630
Avoided roof replacement costs: $271,970 over 40 years
Tax credit: One-time break of $67,130, after installation
Increased rental income: $72,150 annually (assuming no vacancies)
Stormwater fee reduction: $3,490 annually
The NRDC estimates the savings for this building over 40 years at nearly $1.9 million; and it goes into further detail about the savings over time for multi-family apartment buildings and retail centers as well.
The NRDC also highlights the benefits over time of infrastructure like green rooftops versus conventional ones, noting that a green rooftop typically lasts 40 years while a standard roof lasts for 20. "For example," states the report, "in a midsize retail building (with a 40,000-square-foot roof), a green roof could avoid a net present value of over $600,000 in roof-replacement costs over 40 years; a medium-size office building, with a roof half that size, could save over $270,000."
The green rooftop on Chicago's City Hall-County Building yields $3,600 in annual energy savings, according to the NRDC. (Photo credit: TonyTheTiger via Wikimedia Commons.)
In addition to citing cost savings, the report also lists unquantifiable benefits, including ones you might not expect, like reduced crime, for example. Here's what it says on that subject:
Recent research indicates that green infrastructure even has the potential to reduce crime on private properties, especially in urban areas. Crime reduction is associated with specific types of vegetation, such as open space covered with
grass and tall trees. Shrubs and bushes, if situated in places that provide places for criminals to hide, have been found to increase crime; however, they can be designed and arranged to minimize impacts on sight lines, providing pleasant places for people to gather and thus improving safety and security.
While the NRDC's findings don't spend a ton of time on the upfront costs of this infrastructure, the report does touch a bit on the costs of some upgrades. Here's what it says about permeable pavement:
The capital costs of permeable pavement systems range from about $2 to $6.50 per square foot for porous concrete, $5 to $10 for interlocking pavers, and $1.50 to $5.75 for grass/gravel pavers. By contrast, the cost of traditional asphalt is about $0.50 to $1.00 per square foot... despite the higher capital costs, permeable pavement systems can have lower annual maintenance costs, resulting in lower overall life cycle costs compared with conventional pavement. The cost-effectiveness of different types of permeable paver systems depends on site-specific conditions.
But are these savings enough, or will city developers require extra pressure from the government in order to green their infrastructure? Just last week, Los Angeles became the first major city to pass a new building code
requiring all new and refurbished homes to have "cool roofs." Perhaps this type of intervention is what's needed to really spur more upgrades?
Anyone visiting this site knows that investing in green infrastructure is a key step forward for our future cities, and one that commercial property owners must get on board with. And, at this stage, I'd bet most property developers are aware that green brings savings over time. But even still, without extra pressure from the government and private sector, these potential savings may not be enough for the most skeptical among them to foot the bill up front.
— Nicole Ferraro, Editor in Chief, UBM's Future Cities