By Scott Boylston
The first law of thermodynamics is founded on the observation that energy can neither be created nor destroyed, it can only be transformed; human energy certainly fits within that framework. So, as the energy dedicated to developing Emergent Structures projects and collaborations increases, the energy dedicated to blog writing (blogergy?) has a tendency to wane.
The last month has seen many developments for Emergent Structures, and there are several forthcoming posts that will present educational and industry outreach projects that have already been designed, not to mention notice of our incorporation as a non-proft entity. But before we get to them, we just want to supply an update on some of the actual reclamation initiatives taking place. The chart in our last post has provided an informative roadmap. So, over the next few days (yes, we’ll post more than once in a week!) we’ll describe some of the recent developments by using that graphic as an aid. We’ll begin with Initiative 2:
INITIATIVE TWO: Savannah Gardens Redevelopment
NorSouth Construction, the General Contractor for Phase One redevelopment, has embraced their role as cutting edge reclamation advocates, and since initiating a relationship with them this past winter, we’ve been constantly impressed by their dedication to increasing reclamation yields. McLendon Enterprise has won the demo bid, and also seem eager to participate in our reclamation efforts. There were five areas we identified for potential on-site repurposing; studs to trusses; please curb your porch; bricks; wallcaps; and tubs of aggregate. Below are updates on each of these.
STUDS TO TRUSSES is the brainchild of Brian Quigley, the NorSouth project manager for Phase One. The idea is to repurpose reclaimed studs from the old buildings for new floor trusses in Phase One that will be manufactured less than 60 miles away from Savannah. The alternative bid for the demolition of these first 39 buildings includes a clause requiring 9,000 studs to be reclaimed and hauled to a work space for denailing, at which point they will be hauled to the truss manufacturer. This reclamation process will be occurring in some time August, and we’ll be sure to share photographs and insights. We will engage several organizations for this effort, and use it as a learning opportunity for creating more efficient methods, and as a training opportunity for green job initiatives.
Because we have planned from the beginning to use Savannah Gardens as a model to learn by, we’re doing something that many designers find frightening:
we’re using math.
For instance, it takes about 40,640 BTU to manufacture one new stud. Repurposing 9,000 studs from Phase One effectively eliminates the need to manufacture 9,000 new studs, and the energy required to manufacture 9,000 new studs is approximately 107,198 kW h, which translates (using US EPA numbers) to 166,157 lbs of carbon dioxide.
That means this first entry under Initiative Two will reduce carbon emissions by approximately 75 metric tons.
Now, we know a more accurate estimate will be forthcoming when we can assess just how many trusses result from this effort, then estimate the energy needed to make a new truss minus the energy required to manufacture the repurposed studs into the trusses. But, for the time being, we estimate that anywhere between 50 and 75 metric tons of carbon emissions will be eliminated from Phase One construction through this one measure.
PLEASE CURB YOUR PORCH
Mike Hughes, project manager for Thomas & Hutton Engineering, has also been a big supporter of our efforts from the very beginning. Immediately after a presentation that SCAD Design for Sustainability students made this past winter on innovative re-use opportunities at Savannah Gardens, Mike initiated the idea of repurposing the large cement slabs that comprise the old porches on site for use as parking lot curbs in the new development. This, of course, is a big winner for everyone due to the sheer weight of these objects, and the fuel that would otherwise be required to haul them to a landfill, or the energy that would be required to crush them on site for aggregate coupled with the energy required to manufacture and haul new curbing. While we have not done the numbers on this part of the project yet, we will be calculating the fuel, cost and emissions savings as it develops.
BRICKS (sorry, no catchy name for this one yet)
As you can see from our past efforts, there are plenty of bricks on site, but the time required to prepare them for immediate re-use in Phase One cannot accommodate the developer’s schedule. So, bricks that have been reclaimed from other local projects will be used, while the Savannah Garden bricks will be stored so that the mortar can be removed at a more forgiving pace, and reused at a later date. We intend to use the process of preparing the bricks for reuse as an educational and green jobs training opportunity.
This highlights the importance of having a dedicated reclamation expert available within the region, and we are fortunate to have one such expert on the Emergent Structures board of directors; Ramsey Khalidi of RK Construction and Southern Pine Co. Ramsey will be providing 225,000 reclaimed bricks for NorSouth’s Phase One construction.
By eliminating the demand for 225,000 new bricks the carbon footprint of Phase One will be reduced by 32 metric tons (that’s in addition to the 75 metric tons saved by the Studs to Trusses project above). Here’s how we arrived at that number: 225,000 bricks is equal to about 737 US tons of brick total. Multiple that by 2,640,000 BTU (energy required to manufacture a singe ton of bricks of this size), and you get 1,945,680,000 BTU.
If 1 kW h is equivalent to 3412 BTU, there is a reduction of 570,246 kW h of energy. As far as greenhouse gases goes: .0434 metric tons of carbon are released for every ton of brick, and that means that 31.98 metric tons of carbon would be released if you were to make 225,000 bricks for Savannah Gardens instead of using reclaimed brick.
WALLCAPS AND TUBS OF AGGREGATE
Yeah, yeah, we’re still working on those. They’re likely to happen since they’re relatively less complicated than the ones we’ve just written about. And because they’re easier to manage, frankly, we’ll get to them when it’s time to get to them.
So, there’s the update on Initiative Two. Come visit tomorrow for an update on Initiative 3….no, really…tomorrow.