Cool It With Concrete

“Cool It With Concrete”

By Paulette Salisbury, FCSI, CDT

How can the color of a pavement make it more sustainable? The answer lies in the materials chosen by design engineers and public works agencies. Long known for its durability and strength, concrete has withstood the test of time on millions of miles of highways and local streets and roads. Now another attribute of concrete pavements is emerging as a benefit to owners, engineers and citizens. Concrete’s light color improves light reflectivity and makes it a cooler material for pavements, roof tiles and building facades. Concrete has been recognized as a solution to the Heat Island Effect by the US Secretary of Energy, Dr. Steven Chu.

Urban areas are usually warmer than their rural surroundings, a phenomenon known as the “heat island effect.” Heat islands can affect communities by increasing summertime peak energy demand, air conditioning costs, air pollution and greenhouse gas emissions, heat-related illness and mortality, and water quality.

Portland cement concrete absorbs less energy from light so it stores less heat and thus has a cooler surface temperature than black pavements such as asphalt. Typical summertime pavement surface temperatures can range from 120-150 degrees. Dark pavements hold heat internally and re-release it at night. Hot pavements also heat stormwater and run-off that flows into local waterways decreasing the water quality and its ability to support plants, fish and wildlife.

In many U.S. cities, pavements represent the largest percentage of a community’s land cover, compared with roof and vegetated surfaces. As part of EPA’s Urban Heat Island Pilot Project Lawrence Berkeley National Laboratory is investigating the impact of utilizing light-colored paving materials including concrete to reduce temperatures and the green house gas (GHG) emissions associated with energy production.

While decision-makers generally choose paving materials based on the function they serve, many private and public owners are considering how the pavement can provide a dual role in reducing energy bills from excessive air conditioning as well as providing a smooth, stable long-lasting driving or parking surface. Studies show that parking lots typically make up a large portion of paved surfaces in urban areas and therefore most of the research has been done on them. Streets, roads and highways also have a significant impact on urban temperatures. Support is growing among public works agencies for using concrete overlays on asphalt roadways to improve the longevity of the pavement and increase reflectivity thus “cooling” the environment. Recent “thermographic” images show the ambient temperature an average of 15 to 20 degrees cooler on concrete surfaces than asphalt pavements.

The US EPA’s Cool Pavements Compendium indicates that concrete is one of the most readily available solutions for the heat island effect. They also explain that concrete’s high albedo or solar reflectance is 40% compared to black asphalt at 5%. Concrete’s albedo can be increased to 70% by using slag or white cement. (http://www.epa.gov/heatisld/resources/pdf/CoolPavesCompendium.pdf ).

Even when a concrete pavement is worn and dirty its solar reflectance is high (about 25%) while asphalt may get lighter in color as the petroleum-based matrix wears away or ages reaching a maximum reflectance of 15-20%. At this point the asphalt usually needs to be resurfaced in a perpetual maintenance cycle making it black again diminishing its solar reflectance.

Concrete’s light reflectivity makes it an ideal material to enhance night time visibility. An AASHTO standard illustrates that illumination demands are roughly 40 to 50 percent lower for concrete pavements than for asphalt pavements. Another report comparing the two pavement types suggested a cost savings of as much as 31 percent in initial energy and maintenance costs for lighting concrete pavements. This finding is important for municipalities where utility costs associated with street illumination are often a large budgetary item.

In order to create sustainable communities architects, engineers, public works agencies and all government officials need to embrace all options. Concrete as a building and paving material is clearly one of the most promising solutions.

"If you look at all the buildings and if you make the roofs white and if you make the pavement more of a concrete type of color rather than a black and if you do that uniformly, that would be the equivalent of... reducing the carbon emissions due to all the cars in the world by 11 years – just taking them off the road for 11 years.”

Stephen Chu – Energy Secretary

ASHRAE San Joaquin Chapter Meeting

Heavy Question: Can Green Building Save The Planet?

Experts in architecture and design gathered in New York recently to talk about green building, and its role in sustainability and all things environmental.

Discussion ranged from controlling impact, incorporating nature into design and even got into the definition of "green." A lot of ground was covered. Here's a link to a recap in smartplanet.

Sierra Leadership Institute Energy & Climate Program

January 6, 2011

FOR IMMEDIATE RELEASE

Media Contact:

Program Manager, Betony Jones, betony.jones@gmail.com, 530-563-8384 and Communications Director, Nikki Streegan, nstreegan@sbcouncil.org, 530-582-4800

Climate Change Optimists: program sees opportunities for Sierra Nevada Communities

Green energy and climate change innovators on the verge of greatness listen up. A group of unlikely allies are throwing down the gantlet to encourage Sierra Nevada community teams to take their percolating ideas to the next level at the Sierra Leadership Institute’s Energy and Climate Program 2011.

Over the past decade, 300 community leaders from Lassen County to Mariposa County have graduated from Sierra Business Council’s innovative Sierra Leadership Institute. This year the institute will shift its individual leadership focus to team-building and collaborative leadership skills with a climate change and green energy imperative.

“Individuals will apply for and attend the program as part of a community team representative of their community’s diverse interests,” says Steve Frisch, president of the Sierra Business Council (SBC).

The five-day workshops will be hosted in Auburn, Calif. and build upon SBC’s existing institute to create a model focused on energy and climate issues. In addition to the traditional leadership skill-building segment, SBC will provide energy and climate training and support team projects in these areas to demonstrate that climate change presents opportunities, not just challenges, for Sierra communities.

From biomass and solar technologies to water conservation and energy saving innovations, possible areas of concentration are limited only by the imaginations of the applicants.

Betony Jones, founder of Fourth Sector Strategies, one of the institute’s developers, explains the ethos behind its new direction.

“It’s about working with community teams and giving them the collaborative and technical skills and resources to implement projects,” she says. “Communities can turn climate change obstacles into financial savings and investment opportunities. The talent and the resources are here. We have a program to get them together and put them in action.”

The Sierra Business Council (SBC) is now accepting applications for the Sierra Leadership Institute to provide fully funded leadership training and technical project assistance to teams around the Sierra Nevada. Successful applicants will be awarded a full tuition waiver, room and board for participating.

Five teams consisting of four to six individuals will attend a week-long training workshop, June 20-24, 2011 in Auburn, Calif. Participants will learn collaborative leadership skills with special attention to the climate and energy policy landscape in California, climate and energy science, California energy regulatory agencies, energy efficiency strategic planning efforts, and opportunities and resources for clean energy transformation. Importantly, after the course program staff will provide technical assistance and guidance to turn concepts developed in the course into viable pilot projects.

SBC is partnering with a variety of state and national partners and funders on different components of training and leadership courses they refer to as the Green Prosperity Initiative. The program is primarily funded by Pacific Gas and Electric Company as an Innovator Pilot Project. The overarching regional Green Prosperity concept is part of the California Stewardship Exchange, coordinated by Collaborative Economics and funded by the Morgan Family Foundation.

Please contact Sierra Business Council at 530.582.4800 or visit www.sbcouncil.org/SLI for more information. Deadline for the application is March 4, 2011.

Net-zero construction gains a foothold

A net-zero building consumes no more energy than it produces.

Cool idea but until recently was about as practical as living off the grid in a yurt. OK for some but hardly a sales feature Joe Sixpack would embrace.

The mere mention was limited to science fiction stories like "Logan's Run," in which the hero escapes with his life from a closed net-zero society of limited resources that could support only a limited population. In 2116, residents in the story who turn 21 are killed.

Net zero, however, has eclipsed such apocalyptic visions. In fact, it's arrived.

Down in Fort Lauderdale, a company that last year decided to build all its new locations to the exacting Leadership in Energy and Environmental Design, or LEED, platinum standards decided to go a step further. TD Bank, which has more than 1,250 locations on the East Coast, is building a bank officials say will be the first registered in the U.S. Department of Energy's net-zero energy building, or NZEB, classification system.

The reason, said Jimmy Hernandez, a TD Bank spokesman based in New Jersey, is relatively simple.

"It just makes sense," he said.

Hernandez said bank officials learned that for a little more than what achieving LEED energy efficiency standards cost, they could add solar panels and actually produce more energy than they consume. And the solar panels will eventually pay for themselves, he said.

The bank will consume about 97,000 kilowatt hours of electricity a year to operate but produce at least 100,000 kWh.

Buildings consume about 40 percent of the overall energy and 70 percent of the electricity in the United States, according to the National Renewable Energy Laboratory. Many efforts are under way to reduce that and in the process lower production of greenhouse gases.

Those measures include sustainability policies from some of the largest publicly traded U.S. companies, measures by states to increase efficiency through building codes (California's new rules took effect Jan. 1), efforts by the U.S. Department of Energy to fund energy efficiency retrofits in municipal government buildings across the country, the whole house and passive house movements to increase efficiency in residential and commercial buildings and a number of others.

An NREL report, "Zero Energy Buildings," says "energy consumption in the commercial building sector will continue to increase until buildings can be designed to produce enough energy to offset the growing energy demand of these buildings."

To address that trend, the U.S. Department of Energy is seeking to develop the technology and a knowledge base for cost-effective zero-energy commercial buildings by 2025. NREL already has created a classification system for net-zero energy buildings to aid in the standardization process.

Buildings aren't the only target. A move is afoot in the San Joaquin Valley to bring solar to the region's farms and use untapped or marginal lands to produce energy. That effort remains in its infancy but could show big dividends and additional revenue streams to farmers, who are themselves big energy users.

Photo: TD Bank branch in Fort Lauderdale, Florida.

US builds LEED embassy in Addis Ababa

President Obama in his State of the Union address challenged America to get 80 percent of its electricity from clean energy by 2035.

Optimistic? Perhaps. But look at it this way: Many of the heavyweights in corporate America already have jumped on the energy efficiency and sustainability bandwagon. GM, GE and Procter & Gamble are among recent professed converts. And U.S. government agencies have been going all out with the concept, doing more with less energy as far away as Addis Ababa, Ethiopia.

The site on the African continent is rather exotic and about 7,000 miles from the nation's capital. But a new building there -- that integrates green building techniques and was one of the first Leadership in Energy and Environmental Design, or LEED, registered facilities in Ethiopia -- provides a glimpse of evolving building trends regardless of location.

The facility, the $157 million U.S. Embassy, features high-efficiency mechanical chillers; variable frequency drives, or VFDs, for all pumps, fans and motors over 5 horsepower; instantaneous water heaters; and a building automation system, said Christine T. Foushee with the U.S. Department of State's Bureau of Overseas Buildings Operations, in an email.

"The automation system allows the facility manager to view equipment consumption, schedule equipment run-times, and shut down systems when they are not required," Foushee said.

The embassy, which was completed last fall and dedicated this week, measures about 205,000 square feet and covers several buildings at the foot of Entoto Mountain, according to officials. The complex provides about 1,000 jobs. The builder was B.L. Harbert International of Birmingham, Ala., and the architect Page Southerland Page of Arlington, Va.

Other energy-saving features at the embassy include occupancy sensors that automatically turn off lights, automatic daylight dimming illumination for fixtures adjacent to windows, energy efficient compact fluorescents and light-emitting diode, or LED, lamps and electronic lighting ballasts. Energy saving is estimated to be 14 percent lower than the American Society of Heating, Refrigerating and Air-Conditioning Engineers standard established in 2004.

And more State Department buildings like the embassy are coming. The Bureau of Overseas Buildings Operations has seven projects in design or construction in Africa.

The energy efficiency movement and push to incorporate renewable energy and alternative fuels are well on their way. In the just released "State of Green Business 2011" report, Joel Makower and the editors of GreenBiz.com write that a dramatic shift is occurring in business despite the lingering effects of recession.

"Companies are thinking bigger and longer term about sustainability — a sea change from their otherwise notoriously incremental, short-term mindset," the report says. "And even during these challenging economic times, many have doubled down on their sustainability activities and commitments."

The Obama Administration directed $3.2 billion under the American Recovery and Reinvestment Act to the Energy Efficiency and Conservation Block Grant program, targeting inefficient lighting and electrical systems across the country for retrofits. Once completed, the program will enable local governments and others to reap huge saving on utility bills. And it will no doubt provide a further example to businesses and residents that they can do the same thing.

Likewise, domestic security efforts by the U.S. military to ween itself from imported fuel offer a high-profile example to consumers. Last month for instance, the Navy said at a symposium that is moving forward with aggressive targets, including reducing petroleum use in its commercial fleet by 50 percent by 2015 and getting half its energy from alternative sources by 2020.

Obama said: "Some folks want wind and solar. Others want nuclear, clean coal and natural gas. To meet this goal, we will need them all."

Just what technology will win out or if all alternatives will be embraced remains a question. The Greenbiz.com report says great transformation is taking place. But its authors ask whether the public take notice and whether political leaders will "position themselves at the front of this parade?"

That of course depends on many factors. Economics will play a big role. Renewable energy remains a premium, but parity is coming closer with technological advances. And there's the price of oil, which is trading in the $91 per barrel range and is forecast to climb to $105 in the next year by oil-price.net.

'Passive' house saves 90% on energy bills

The Cleveland Museum of Natural History plans to build a house on its grounds that will be so well insulated, so weather tight and so efficient that it will need no furnace.

That's right, no furnace. And Cleveland can have some nasty, bone-chilling weather.

The house is of the "passive" variety, a movement gaining major steam in Europe and apparently here too. The superinsulated home boasts 18-inch walls, triple-pane and glazed windows and overall efficiency that should make it one of the museum's biggest attractions when the house opens for three months in June 2011.

"You can walk around barefoot in the middle of winter where there are no drafts, no cold spots," said David Beach, director of GreenCityBlueLake Institute, which is the center for sustainability at the museum, in a video on the official site. "And it's a wonderful place to live."

No doubt. But it's hardly the norm.

Buildings account for about half of global energy consumption and greenhouse gas emissions. There's a big push nationally and worldwide to address that with retrofits, upgrades and better building practices through efforts like the U.S. Green Building Council's LEED building certification system, which was designed to improve energy savings, water efficiency and CO2 emissions reduction.

Adoption of more stringent building practices would make a big dent in greenhouse gas emissions and energy use.

But for consumers adding energy efficiency means lower energy bills. Way lower with a super-insulated house. For instance, my house was built in 1961 with 2-by-4 walls, single-pane windows and no insulation in the floors. I blew in a bunch more insulation in the ceiling, replaced the windows and upgraded the heating system to a 95 percent efficient furnace. My bills dropped like a rock.

My co-worker Sandy Nax lives in a 1990s vintage home with 2-by-six walls and stock double-pane windows. He's got a better design. Even so, his cooling costs in the summer sometimes exceed $500 a month. Mine's smaller, and it's cheaper.

Both of us would love to lower our bills. Like many who chose the newspaper profession, we got used to low pay and being frugal. We lived in pretty dicey places at the start of our careers.

Many others trod the same road, learning along the way that saving money is practical.

The Cleveland Museum believes people will appreciate the benefits of the passive design once they tour the exhibit. Beach, the museum official, said he hopes the concept will catch on, certainly in his own city where it adoption by builders and architects could "bring industry to Cleveland." The Passive House Institute U.S. says, the design technique "provides a solution that puts true carbon-neutrality within reach. Today."

And why not. U.S. Green Building Council Central California Chapter official Loren Aiton has said that adding energy efficiency and other measures to buildings add relatively little to the overall cost.

Still, upgrades come at a premium. LEED standards are graduated, starting with little or no difference in cost to tacking on 4 percent to 10 percent or more. The higher gold and platinum standards cost more to implement. But the savings are greater.

Chuck Miller of Doty & Miller Architects, who designed the Cleveland project, said the passive house was crafted to look conventional inside and out. While materials cost more initially, he said, "it will be a more affordable house over time. It will use 10 percent of the energy of other homes."

Back to that furnace or lack of one. Miller said the house will boast "very sophisticated ventilation and heat recovery equipment."

My friend lives in a small town just south of Tacoma, Wash. and has ducted electric heat. The system is very inefficient. He weatherproofed his home and added a plug-in heater -- an EdenPure, pitched by Bob Vila -- that uses light bulbs to generate heat. He dropped his winter electric bill 40 percent. And the mobile heater keeps his house just as warm.

It just goes to show that the efficiency concept is sound and can be done in different ways.

At summer's end, the Cleveland house will be moved to a permanent site a few blocks from the museum where it will be sold to a family. There it will continue to save its owners money, even in winter. And that's saying something. For instance, Cleveland has an average January temperature of 30.7 degrees. When I looked on Weather Underground, it was 21.3 degrees with a wind chill of 13 degrees.

That passive family will be toasty.

And others could be too. I've written in the past about Ed McGrath of superinsulatedhouse.com who began pushing many of these ideas decades ago. I can't help but think he'd be impressed.

Photo: Passive house is the one in the center. Courtesy of Doty & Miller Architects in Cleveland