Green Roof Resource

To update from a previous post, not only did US Court of Appeals District of Columbia Circuit rule that the clean air mercury rule violated the Clean Air Act in February, but in July the District of Columbia Circuit also vacated the clean air interstate rule (CAIR). While the court vacated the CAIR rule, the NOx State Implementation Plan is still valid. However, as the NOx Budget Trade Program (BTP) was set to expire prior to the 2009 ozone season to make way for CAIR, state regulators have been urged to revise their programs to extend the NOx SIP call. Meanwhile, on September 24th the US filed a petition to the court for a rehearing of the CAIR case.

So why should we care about CAIR or the NOx BTP? The NOx BTP has effectively reduced NOx emissions by 74% between 1990 and 2006 [1]. The ozone season NOx emissions have dropped from 1.86 million tons in 1990 to 491 thousand tons in 2006. During the same period, the 8-hour average ozone concentration decreased across all states participating in the program with significant reductions occurring in New York, Pennsylvania, Virginia, and West Virginia [1]. While there remain areas that are not in attainment of the 8-hour ozone standard, most areas within the NOx BTP have shown improvement suggesting that there is a benefit to implementing such a program whether the CAIR ultimately is accepted or the NOx BTP is extended.

Reference:
[1] US EPA. Office of Air and Radiation. NOx Budget Trade Program: 2006 Program Compliance and Environmental Results. EPA-430-R-07-009. 2007.

With the opening of the Olympic Games a few days away, air quality in the city is increasingly a concern. It is now possible to view air quality around the city thanks to a joint effort by Mapufacture, Inc. and Fortius One. The map shows values from air quality sampling stations around Beijing, China.

The air pollution index (API) indicates air quality for SO2, NO2, and PM10 (particulate matter that is 10 micrometers in diameter or less). The API cannot be directly compared to other air quality indices from other locations. The USA and Canada both use AQI, air quality index, which is similar to API but the indices are set according to different formulas based upon concentration. Hong Kong uses a different API, which can cause confusion when comparing the air quality of the two cities. While the indices cannot be compared, each index is used to evaluate when the air quality is safe or dangerous to public health according the location’s guidelines. The API for Beijing has the following ratings:

Generally, an AQI or API is set such that ratings of 100 or below are safe while ratings above 100 may be dangerous to at least some of the population. However, the formulas vary, and the specific concentration of that threshold varies according to the country or location where the index is used.

The World Health Organization (WHO) has established guidelines according to concentration, which is much more straightforward. Using concentration allows for comparison of air quality across borders. However, even the standards issued by the WHO are not standardized across pollutants (in time) as you can see below.

Source: WHO. 2006. WHO Air Quality Guidelines for particulate matter, ozone, nitrogen dioxide, and sulfur dioxide. WHO/SDE/PHE/OEH/06.02

While we can now view daily air quality in Beijing, where within the city the data is taken, and the proximity of the sampling stations to the Olympic venues, we are not able to compare it to WHO standards. Nevertheless, this is still pretty neat.

A few weeks ago, I participated in a conference call for bloggers to learn more about the green building efforts of Genzyme, a biotech company focused on diagnostic testing, pharmaceuticals, and medical treatments. In addition to its headquarters building in Cambridge, Massachusetts (a LEED Platinum building), Genzyme has several additional buildings seeking LEED as well as a few green buildings internationally.

What I found most interesting were the efforts to green research laboratories. Genzyme is presently seeking Silver LEED accreditation for its research laboratory in Framingham, Massachusetts and has a proposed research building in Beijing, China. Much of the work in the Framingham laboratory focused on lighting and daylighting, radiant heating and cooling, and a highly reflective roof. One of the challenges with laboratories is the added energy expense of once-through air systems. Achieving LEED standards for laboratories can be more difficult than standard commercial buildings as laboratory buildings are more energy and water intensive (the average wet lab uses five times as much water and energy as a typical office building per square foot).

Yesterday the House Subcommittee on Energy and Air Quality (part of the Committee on Energy and Commerce) held a hearing focusing on building energy efficiency as one method of tackling CO2 emissions. The subcommittee is presently developing and understanding various potential mechanisms to reduce greenhouse gas emissions by 60-80% by 2050 in a manner that limits costs to the economy and maximizes the efficiency of a mandatory climate change program. They have produced a white paper that analyzes cap-and-trade program options. While developing cap-and-trade programs will most likely focus on large-scale stationary sources and transportation, yesterday’s hearing demonstrated that members of Congress recognize and are exploring the significant reductions that can occur through improving the energy efficiency of our buildings. Wahoowa!

One of the facts that was mentioned multiple times during the hearing is that building stock represents 40% of total US greenhouse gas emissions. To reduce emissions by 60-80% by 2050, improvements in building efficiency must be made. The committee recognizes that sizable reductions can be made through improved building energy efficiency. Last year the committee and the House passed a new building code to states to advance energy efficiency, but the legislation was stopped by Senate action. The witnesses spoke of several different programs and efforts to formulate a national building energy efficiency policy. The challenge appears to be to create incentives to further energy efficiency without setting standards that are unachievable or of limited use depending upon the location of a building project.

Here are a few of programs and efforts that were mentioned in the hearing:
The 30% solution: The Energy Efficient Codes Coalition has launched a campaign to improve residential energy efficiency standards by 30% from the 2006 international energy code standards. In September, this will be decided at the International Code Council Annual Conference in Minneapolis, Minnesota. The 30% solution is designed to be achievable, affordable, and enforceable. This is the most promising effort for enforceable change in building construction at the moment, but we’ll see where this stands in two months time.

“Beyond code”: This was another often used phrase yesterday. This refers to voluntary program such as EnergyStar. I’ve mentioned EnergyStar before, but another source for energy efficiency ideas is EnergySavers, which provides energy information and tips from DOE, EPA, and HUD.

With representatives talking about efficiency targets and executive agencies and departments collaborating, change is certainly coming. Who knew that “state of the shelf” technologies could be so exciting?

Here’s an update on NYC green roof policy incentives as discussed previously. According to an article in Greener Buildings, bill A 11226 passed the state assembly on June 23rd. The senate had previously passed the bill on June 11th. For buildings that green at least half of the roof surface, they may receive a one-time tax credit of $4.50 per square foot (up to $100,000) of green roof.

So how does $4.50 per square foot compare with the cost of a green roof? In our study on the costs and benefits of extensive green roof systems, which included costs to install the conventional components in addition to the green components, we found that 4 inch systems were on average $22 per square foot. An intensive system would certainly cost more, and there are certainly variations in this price. Assuming this price per square foot, the incentive covers about 20% of the cost. By reducing the upfront cost with an incentive, the time required for a return on investment (ROI) is reduced considerably. Considering only energy savings and a reduced stormwater fee, typically the average green roof takes 20 years before ROI can be reached. With the additional incentive, this can reduce the time required for an average roof to 12 years. Not a bad deal.