Monday, March 31, 2008

Journal #17: Environmental Practices in Construction - LEED

I am going to use this journal entry as another step in my independent project of a summary, analysis, etc... of current environmental practices in construction. In an earlier post, I discussed AASHTO's efforts to educate workers and foreman to create more environmental conscious sites through the daily inhabitants. I took a look at the LEED rating system again and summarized what I thought were the aspects that were directly related to construction management.

SS Prereq. 1: Construction Activity Pollution Prevention

This is a required part of gaining a LEED certification which states that there must be a certain level of soil control: soil water runoff, dust control, and soil reuse. This, I feel, is almost mandatory at every construction site. Even at the strip mall sites I worked at over the summer soil was always reused as part of cut/fill or sold to other sites, and dust/runoff control were absolutely necessary in order to gain construction approval from the local government. Any complaints from the community would immediately result in problems for scheduling (noisy/dusty night shifts were shut down). So this isn't asking too much of a contractor to comply with.

MR Credit 2.1: Construction Waste Management: Divert 50% From Disposal

This credit is worth 1 point and promotes attention in waste management during construction. It requires that 50% of all non-hazardous construction and demolition debris be salvaged or recycled. This is definitely a good point, as a construction manager would have to plan and implement a series of standards that all parts of the project would comply to in order to meet this waste quota. However, get a construction manager who is good enough at debating and he/she could convince the US Green Building Council that recycling is less environmentally sound than landfilling. Look out LEED, Carnegie Mellon's life cycle analysis is about to slap you in the face.

MR Credit 2.2: Divert 75% From Disposal

Just an extension of MR 2.1, and adding another point if you are a better recycler... but is there any room for source reduction efforts in construction? I guess that just falls under the category of "salvaged materials."

EQ Credit 3.1: Construction IAQ (Indoor Air Quality) Management Plan: During Construction

This credit focuses promoting better air quality for construction workers during construction, which ultimately leads over to better air quality for the permanent occupants. The requirements include protecting absorptive materials from moisture damage, air filtration control (if applicable), and sheet metal/air conditioning standards. The filtration systems must be replaced before any occupancy, and includes proper control of the HVAC system. The credit seems like another valid point, and could create a better work environment possibly resulting in increased productivity. There is a related credit that has to do with IAQ for pre-occupancy that involves a flush out, with fresh air, of the building before occupancy, or air testing.

That was all I could find that cited the construction process in the new construction rating system. However, I was told by my advisor for next year that there was little being implemented by construction organizations for environmental practices, and to look through published papers which is my next step.

Tuesday, March 25, 2008

Journal #16: Green Practices Using BIM

I've been checking up on the news releases at BuildingGreen.com, and read an article about the new efforts to make building information modeling (BIM) compatible with energy modeling practices. The two major forces in BIM software are Autodesk (Revit, Autocad) and Bentley Systems, and both have recently acquired software companies that incorporate energy modeling. As BIM has been presented to me in classes, it focuses on recognizing problems in the 3D design (such as a pipe going through a column) and site layout (wrong elevations or materials). This is supposed to create a 'smart' CAD model that finds problems before they are encountered in construction and end up costing money and time (which is ultimately more money).

For Bentley, this is primarily going to be done through Hevacomp, Ltd., technologies that analyze materials for structural integrity and load capacity. They also analyze materials for amounts of carbon and provide energy-use simulations. Autodesk has also acquired two companies; one that specializes in translating BIM data into energy-use models and another that also analyzes building materials but provides other information such as indoor pollutant concentrations.

I had never really thought of BIM having energy and environmental elements, but now it seems like a very logical step. I know a lot of large contractors (PJ Dick, Turner) try to incorporate BIM into every project possible, but receive some reluctance from subcontractors, and almost every architecture firm (The PJ Dick speaker had said they have not received cooperation from a single architecture firm.) The new energy and environmental aspects I doubt will have an impact on the number of cooperating subcontractors, but possibly could lure architecture firms if they are keen on marketing themselves as eco-friendly designers. Also I began to think if this could be incorporated in LEED, and got very excited at the prospect of using BIM and LEED together, as the 3D model could become a calculator for how environmental sound your materials and design are.

Thursday, March 20, 2008

Journal #15: Oil Sands, Corn Ethanol

The past two classes have seemingly made the outlook on the possibilities for alternative energy sources bleak. It has become more clear to me over the semester that almost any new energy source, waste management method, or emissions reducer can be proven to be just as harmful to the environment/economy as the previous method using Life Cycle Analysis.

Corn Ethanol is easily marketed as environmentally friendly and clean with agriculture being the primary source, although a large amount of energy is necessary in the entire fermenting/refining process. Although it is incredible that we are able harness substantial amounts of energy from my favorite popped snack, it reminds me of reading Grapes of Wrath in 10th grade. From the estimation calculations we performed in class, it doesn't seem remotely possible to produce a large enough amount of crops to make this a sustainable alternative.

Oil Sands, one of the major facets in reducing our dependency on middle east oil sources, was presented as deceptive in that the refining process is more harmful to the environment than the current resources. To me, it reinforced the urgency that must be placed on reducing the dependency on oil, mainly in transportation vehicles. I always felt that as a nation our continuing and increasing dependency came through constant reinforcement that cars, buses, and trucks were absolutely necessary parts of society. Giant roadways and suburban living areas are constantly expand and further underline the need for a vehicle to earn a comfortable living and lifestyle.

Tuesday, March 4, 2008

Journal #14: Carbon Capture and Storage

I couldn't think of a lot to write about after today's class on LCA end-of-life implications, so I went back to the Steinbrenner Institute faculty presentations and took a look at Prof. Edward Rubin's presentation on CO2 emissions. The powerpoint focuses first on the generation of CO2 as it is by far the greatest concentration of any of the greenhouse gases emitted each year. He shows that, as a nation, we are poised to increase the use of CO2 34% by 2030 as coal burning continues to increase as an energy provider.

He shows that vehicles and power plants are the bulk of the products and services generating CO2, and presents some alternatives in reducing emissions: alternative energy, housing changes, reshaping infrastructure... all of which would require massive changes to produce a significant change taking a long time.

The optimal solution, Rubin argues, is Carbon Capture and Storage (CCS), a method of capturing CO2 used in power plants and returning the emissions to deep underground areas where carbon has been depleted (such as oil wells that have been tapped). This saves significantly on energy along with reducing emissions from the largest sector of CO2 generation.

Immediately I was interested in comparing the effect of CO2 emissions (from coal burning) to some other form of energy generation, such as nuclear power. Would the complete life cycle analysis of both energy generations be comparable? Or would CO2 stand out as much more hazardous to our environment? Since the presentation is limited to the environmental effects of CO2 emissions, I think that this type of LCA would also be limited in the same way.