Tag Archives: white roofs

Chicago Marks a Deadly Anniversary

This month marks the 20th anniversary of the deadly heatwave in Chicago, IL, which killed an estimated 739 people and showed that even in northern climates, urban heat kills.  Our world was already warming in 1995, but 20 years ago this northern city wasn’t used to these extreme heat events and many Chicago residents didn’t have air conditioning units in their homes or apartments.  Most of the victims of this extreme heat were either the very young, or elderly people living in poor neighborhoods, too afraid of crime to open windows or sleep outside.

As this article containing first-hand accounts from the key players reports, the residents, city officials and first responders were ill-prepared for such a deadly natural disaster twenty years ago.  City officials were slow to respond.  First responders and hospitals were understaffed and unable to help residents survive the extreme heat.  And residents failed to listen when heat advisories were finally issued.  Heat like this wasn’t supposed to hit a northern city like Chicago after all, and hundreds of people paid the price.

City officials quickly began to look at ways to bring down city temperatures after that tragic heat wave. Chicago was one of the first cities to require the deployment of cool roofing technology.  Their 2001 Urban Heat Island Ordinance wrote cool (green, solar & white) roofs into law, and they’ve been building on that ever since.

This new ordinance is paying off.   Yale researchers reviewedthe changes between 1995 and 2009 in Chicago’s vegetated and reflective surfaces. Researchers found that where reflectivity increased, temperatures went down. Most of the reflectivity increases in Chicago that brought down temperatures were a result of the new reflective roofs that were installed because of the new energy efficiency zoning codes in this northern climate.

Over the past 20 years, deadly heatwaves have hit cities all over the world. In one major disaster, 70,000 people lost their lives in Europe’s 2003 heat wave. Each year, heat records are shattered globally. According to NOAA, 2014 was the 18th straight year where average temperatures have topped 20th century averages in the United States. It was also the hottest year on record. NOAA just released data on the first half of this year showing that 2015 is on track to blow past last year’s records.  These heat-waves are here to stay and are expected to get worse, and city officials everywhere are a beginning to understand the urgent need to adapt in order to protect their residents.

While these first-hand accounts of past heat-related disasters show us how far we’ve come in the past 20 years, it also shows us how important it is to plan for future heat events as our world grows ever-warmer. Research shows that reflective surfaces help bring down urban temperatures and save lives – even in northern cities like Chicago. That’s why city officials around the world are working with GCCA to adapt their cities to our changing climate.

GCCA has released several studies showing how reflective surfaces and cool roofs can save lives. For further information, please follow these links:

Evaluating the Health Benefits of Urban Cooling – GCCA worked with a top team of researchers to study how cool surfaces and vegetation save lives during extreme heat events in Baltimore, Los Angeles, New York City, and Washington.

Assessing the Health Impacts of Urban Heat Island Strategies in the District of Columbia – GCCA finds that cooler surfaces and more green space can save lives during heat waves in Washington, DC.

To learn how cities are working to bring down urban temperatures, please take a look at this report:

Urban Heat Island Policy Survey – GCCA and ACEEE survey 26 cities to learn how they are addressing excess urban heat.

For further information, please visit our Cool Roofs and Cool Pavement Toolkit knowledgebase, where we have over 600 studies, reports and surveys.

American Institute of Architects Recognizes the Benefits of Cool Roofs

In April of this year, GCCA Board Member Greg Kats published a study of the health benefits of cool roofs on Washington DC-owned buildings. After the District retrofitted many of its buildings with white roofs, green roofs, and / or solar collectors the city started saving money. This study turns things on its head by showing that using the old technology of conventional dark roofs is a policy failure that costs cities and building owners money.

Robert Ivy, chief executive of the American Institute of Architects discusses this study, along with other cool roof benefits in this Washington Post guest column. In it, he notes that the highly reflective surfaces of white roofs cut energy bills and can help improve the health of residents and cool cities.

“We’ve known for years that smart roofs save energy, and we’ve been able to come up with methodologies to quantify those savings. However, the health benefits of such design choices have been harder to figure out. The authors of this report, Greg Kats and Keith Glassbrook, have addressed this complex question, and their findings could have an impact on improving the health of residents in urban areas across the nation.

Roofs typically make up 15 to 25 percent of most cities’ surface areas. And because roofs can typically be replaced or retrofitted more frequently than entire buildings, they represent an opportunity for developers and building owners to dramatically cut the “heat island effect” in urban environments …

Use of such techniques, in turn, can have public health benefits, particularly for low-income and elderly residents who tend to be more vulnerable to illnesses related to extreme heat and poor air quality. Moreover, heat mitigation through adoption of cool and green roofs can help ameliorate the effects of heat stress.

The report will prove to be relevant reading for designers, architects or city officials trying to battle the pernicious health effects of urban heat islands. These new methodologies suggest ways for cities to quantify the benefits of their building codes, policies and incentive programs.”

You can read the full report here:
Washington, DC Smart Roof Cost – Benefit Report

A Standard is Born

GCCA Board Member Ronnen Levinson just announced the publication of ASTM D7897-15, ‘Standard Practice for Laboratory Soiling and Weathering of Roofing Materials to Simulate Effects of Natural Exposure on Solar Reflectance and Thermal Emittance’.

This practice was developed and shepherded through ASTM by the LBNL Heat Island Group and by Concordia University, with support from DOE’s Building Technologies Office, and from many industrial and academic partners. It will be used to accelerate the development and deployment of cool roofing materials, and has already been accepted for interim rating of roofing products by the Cool Roof Rating Council (CRRC) and by California’s Title 24 Building Energy Efficiency Standards. The CRRC and LBNL will offer courses at LBNL next month to train and certify test laboratories. Research is underway to adapt the method for use in China, India, and Europe.

While they work with the Berkeley Lab News Center to prepare a release, you can read this earlier write-up describing the acceptance of the practice by CRRC and CA Title 24.  You can also learn more about the method itself in the first half of this eight-minute Science at the Theater talk, Cool Roofs Though Time and Space, and in their 2014 SOLMAT article.

7 Actions for Cities to Seriously Address Climate Change

Cities are where more than half the world lives, and where all future population growth will occur. By many estimates, cities are already responsible for more than half of climate change. While Congress remains dysfunctional, cities are rapidly becoming the most interesting and innovative developers and adopters of programs to cut CO2 emissions. They increasingly are taking on the responsibility of achieving deep CO2 emission reductions that virtually all climate scientists tell us we must achieve.

I participated in the recent VERGE day-long City Summit, and was impressed by how much effort and innovation around climate change reduction is occurring in cities. More than 1,000 U.S. mayors, who represent some 60 million Americans, have signed on to the U.S. Conference of Mayors’ Climate Protection Agreement, committing to cut city-wide CO2 emissions below 1990 levels. Houston, Philadelphia and Los Angeles recently launched the Mayors’ Nation Climate Action Agenda (PDF), a joint commitment to an inter-city cap-and-trade program to reduce CO2 emissions by 80 percent by 2050.

For the most part, however, cities have not yet gotten serious about implementing substantial policies to cut CO2 emissions. Following are seven actions cities can and should take in order to reduce emissions by more than half while saving money.

1. Adopt cool roof, green roof and solar harvesting strategies

Half of city surfaces are roads, parking lots, sidewalks or roofs. These generally absorb over 75 percent of the sun’s energy, converting it into heat that increases urban temperature and global warming, both of which increase smog formation and energy bills. The low reflectivity of these surfaces imposes huge unnecessary social and environmental costs.

It is cost-effective today to double the reflectivity of most city roofs and paved areas. Through the work that Capital E is doing with Washington, D.C., the National Housing Trust, the American Institute of Architects and others, we have found that by adopting cool roofs, green roofs and solar PV on roofs, most cities dramatically can improve comfort and health while cutting energy costs.

Cool and green roofs and solar PV should be evaluated on a full costs and benefits basis — including health — to inform policies.

2. Integrate smart-building platforms with existing systems

City agencies commonly have different building energy management systems and a range of often incompatible energy using devices, controls and systems. Buildings — even LEED buildings — can be made to operate better if they are managed through a smart building platform that integrates with all existing systems, including building energy systems, controls and sensors, and uses near real-time data from these systems to optimize energy use and comfort.

A strategy such as ESCO 2.0 features integrated, near real-time, smart energy data, and controls and optimization to actively manage a portfolio of buildings. A recent NRDC study (PDF) of three efficient commercial buildings, including a newly commissioned LEED building, that adopted a smart-building optimization platform called AtSite cut energy use by 8 to 17 percent with almost no new equipment investment.

One advantage of an ESCO 2.0 strategy is that it allows a shift from expensive scheduled maintenance to maintenance triggered by near-real time equipment performance. Another benefit is improved comfort. This kind of open platform also allows virtually unlimited flexibility in adding in new equipment or applications.

3. Enter into long-term agreements to buy new renewable energy

Today a lot of cities, among other building owners, buy short-term (typically two-year) Renewable Energy Credits. These are in essence transferrable, inexpensive accounting claims for the environmental benefits associated with renewable energy. But in reality RECs are almost entirely from projects that are already completed (often many years earlier), and the RECs have little or no impact on driving new renewable energy investments.

To drive new renewable energy investments, cities should skip RECs and instead contract to buy renewable energy on terms long enough to actually allow new project financing. To do so, cities should enter into long-term purchase power agreements with renewable energy power developers to buy clean energy at fixed rates — typically below the rate they are currently paying.

This long-term purchase commitment means revenue certainty for the project developer, enabling equity and debt financing for project construction. Smaller cities can band together to do larger, joint PPAs for renewable energy, in turn bringing down the cost of clean energy.

These PPAs can be executed by almost any city today, would achieve real CO2 reductions and generally would cut the long-term cost of electricity. City government can invite in-city groups, such as schools and hospitals, to participate in city PPAs to enable even larger cost and environmental savings.

4. Insist that cities’ energy efficiency investments be counted in cap-and-trade programs

About half the U.S. population lives in states with cap-and trade programs (including California and members of the Regional Greenhouse Gas Initiative) that place a dollar value on CO2 as a way to encourage investments that cut CO2 emissions. But while large industries, corporations and utilities can participate, cities are excluded from these programs. This makes no sense.

A national initiative called CO2toEE seeks to allow energy efficiency investments by cities and other building owners to receive the value of the CO2 reductions that result from their energy efficiency investments. This initiative has broad and growing support from state and national real estate and energy organizations and NGO groups — and cities should join to push for this common-sense and important design change in carbon trading programs.

The value of the CO2 received by cities would offset a significant part of the capital cost of deeper energy efficiency investments, increasing the funding for deep energy efficiency investments.

By allowing city and building energy efficiency to participate, cap-and-trade markets also would become larger, deeper and more efficient, and would drive large additional investments into energy efficiency. This is essential if cities are to achieve deep reductions in their CO2 emissions.

5. Measure, count and reduce the CO2 embedded in cities’ buildings and roads

Most cities that count their CO2 emissions and invest in reducing CO2 still ignore the enormous volume of CO2 that results from constructing their buildings, roads and other infrastructure.

Cement production is responsible for about 6 percent of the world’s CO2 emissions. A recent review of California’s 500 mile high-speed train found that it would take about a decade of CO2 emissions reductions from rail trips replacing car, truck and plane trips to offset the CO2 emissions from the production of cement required to build the train’s infrastructure. And it can take an energy-efficient building six or eight years of operations to equal the CO2 emissions from the cement used in construction. In fact, the most recent release of the national green building design standard, LEED v4, awards points for reduction of embedded CO2.

What if, instead of generating CO2 emissions, cement sequestered CO2? What if cities measured their embedded CO2, and then used their infrastructure — roads, parking lots, sidewalks and their buildings — to sequester CO2?

6. Invest in new versions of ancient building products that can reduce or sequester CO2 in buildings

Wood sequesters CO2, and the recent development of advanced structural wood products such as cross-laminated timber allow 10 or 20 story buildings to be built of wood.

A much larger CO2 sequestration opportunity is low or negative carbon cement. Cement, first used by Mesopotamians and Romans, is also being reinvented. Cement produces almost a ton of CO2 per ton of cement (cement is made by burning limestone at over 2500 degrees.) Several companies produce low or negative carbon cement.

The most interesting of these companies is Blue Planet, which sequesters flue gas from power plants in cement, sand and aggregate (cement is combined with sand and aggregate to make concrete). Blue Planet can sequester up to 1,500 pounds of CO2 per ton of cement. In its current work at the DOE National Carbon Sequestration Center and in other partnerships, Blue Planet is targeting an 80-percent CO2 reduction from fossil fuel plants, such as natural-gas fired power plants. The process also sequesters other damaging pollutants, such as PM2.5, heavy metals and NOx.

7. Incorporate best-estimate CO2 costs into design and investment decisions

Even in places such as California that have active carbon markets, the market price for carbon is far below its real cost. Because climate change already imposes large costs, cities increasingly want to account for global-warming costs in their investment decisions.

A dozen federal agencies, including the Treasury Department and the Environmental Protection Agency, developed a rigorous cost analysis called the social cost of carbon (PDF). First released in 2010 and updated in 2013, it found the real cost of CO2 to be in the $40/ton range, with additional identified costs not included. Based on a Congressional request, the report and its methodology were extensively reviewed by the General Accounting Office, which a few months ago issued a report that entirely confirmed the social cost of carbon analysis and findings.

A good strategy — recently adopted by the Federal Green Building Advisory Committee which I chair — is to include the social cost of carbon in all construction and energy-related design decisions. In effect it is revenue neutral because it is used just to make better design decisions.

While this will take years to implement in federal agencies, cities can and should move rapidly to adopt this rigorous and conservative cost of carbon in their own design and investment decisions. This would allow better, more cost-effective investment and design decisions that reflect the real cost of climate change. (British Columbia’s adoption of a substantial cost of carbon helped achieve deeper CO2 reductions, lower overall taxes and faster economic growth than other Canadian provinces that did not adopt a carbon price.)

Enabled by organizations such as the Urban Sustainability Directors Network, C40 Cities and the Global Cool City Alliance, cities have become the most promising and important forum to drive deep CO2 reductions. Cities increasingly have the political will to get serious about climate change and to lead their countries to a very low-carbon future consistent with protecting the planet and future generations from the worst of climate change. The clock is ticking.

This article is based on a presentation Nov. 10 at the National Academy of Sciences/Institute of Medicine.

Disclosure: I work with several of the above companies and organizations as a board member/adviser/investor.

Greg Kats serves on the Board of the Global Cool Cities Alliance.

This article was originally posted on November 13, 2014 at GreenBiz.com. (http://www.greenbiz.com/article/7-actions-cities-seriously-address-climate-change)

Cool Roofs Are Cooling Homes in India

Climate change is driving up temperatures in cities around the world.  When things heat up, many of us simply reach for the thermostat and the air conditioner does its job.  In many parts of the world however, air conditioning isn’t an option and the rising temperatures mean homes become uninhabitable.   But there is a simple and affordable solution – a cool roof can bring down the temperature indoors by a few degrees, which is enough to allow people to sleep in their beds at night.

That’s where programs like the Cool Roof Project – through the Asian Cities Climate Change Resilience Network, and the Rockefeller Foundation – can help.  This program is installing cool roofs in Indore city, India, and residents are already getting relief from the urban heat.  From the Rockefeller Foundation

At Mamta Chouhan’s house, located in one of the 50 locations where cool roof technology has been implemented, a perceptible difference in indoor temperature is seen during high heat days.  The 200 families who have participated in this project have felt similar impacts as well.

Vijay Bhargava, a resident of Indore, reports that TARU came to him and others with an idea to reduce the temperature in their homes. “I didn’t believe it at first,” he admits, “but then they shared the details, including the potential benefits, and I changed my mind.  Afterwards, we felt a five or six degree change.  Incredible!”

He adds that he and his family couldn’t even sit upstairs in the summer before.  “Now, we can sit anywhere in the house, not feeling a difference whether we’re upstairs or downstairs.  It’s meant that we’ve been able to reduce our air conditioning usage substantially.”

They’re collecting data to document the many benefits of this program, and hope to convince local government, real estate developers and other interested parties to include cool roofs in future projects.   Stay tuned!

Urban Heat Island Turns Top Floor Apartments into Ovens

It doesn’t matter where you live – extreme urban heat is a major problem and it’s getting worse.   As the effects of climate change take hold, temperatures are steadily rising – this year is on track to be the hottest on record and there’s no relief in sight for city-dwellers.   Especially those in poorer neighborhoods.

This article from the South China Morning Post about a recent study paints a grim picture for people living in older buildings.   Their homes get hotter and they spend a higher percentage of their income struggling to keep cool.

Low-income dwellers living on the top floors of old tenement buildings have become the forgotten victims of the urban heat island effect, a green group has found.

The heat – trapped in bare, unpainted concrete – dissipates into households below turning flats into “ovens”.

“The rooftops of some of these old buildings can get so hot you can fry eggs on them,” said Dr William Yu Yuen-ping, chief executive at the World Green Organisation, the group that carried out the study.

One measurement at Mong Kok one afternoon measured a maximum rooftop temperature of 74.4 degrees.   The air temperature in the flat below rose to 36.8 degrees, five degrees higher than the 32 degree mean temperature recorded by the Observatory that day.

Yu urged the government and the Commission on Poverty’s Community Care Fund to help these households by offering subsidies for planting rooftop gardens or painting buildings in white to dissipate heat.

Rooftop temperatures of 74.4 degrees Celsius – that’s 165.2 degrees Fahrenheit by the way.  And inside the top floor apartments… over 98 degrees Fahrenheit.   This problem is universal and white roofs can help lower the temperature, reduce energy consumption and save lives.

Study Shows How Increased Reflectivity Can Save Lives

Researchers at the Georgia Institute of Technology recently published a report, in which they took a look at past heat waves in Phoenix, AZ, Philadelphia, PA and Atlanta, GA.

This study shows that by adding white roofs, reflective pavement and trees, cities can counteract temperature increases in urban areas and save lives. From an article byClimateWire

[T]he researchers modeled how the three cities would respond to a minimum green space ratio on land parcels, setting a floor for areas covered with grass, gardens or trees. Vegetation tends to have a cooling effect by circulating moisture in the air that draws away heat during evaporation. Tree canopies also provide cooling shade.

The team also modeled how Phoenix, Philadelphia and Atlanta would behave with more reflective streets, sidewalks, parking lots and rooftops. Higher reflectivity, or albedo, means the area absorbs less sunlight, thereby lowering the temperature.

Stone and his collaborators then overlaid a health impact model.  They found that combinations of increased vegetation and albedo could cut into projected increases in heat deaths, reducing them between 40 and 99 percent. “On average, we reduced the rate of increase by about 60 percent,” Stone said.

Groups like the Global Cool Cities Alliance are now trying to get cities to adopt these adaptation strategies, pitching them as a way to protect public health. However, it’s slow going, given that cities around the country address heat vulnerability differently, if at all.

You can find the full study HERE.

This report parallels a recent GCCA report, which looks at Baltimore MD, New York, NY, and Los Angeles, CA, and shows how reflective roofs and vegetation can cool air temperatures and save lives.

Note: Access to the ClimateWire articles is limited to subscribers.

Catch GCCA Executive Director Kurt Shickman on KCRW

Madeleine Brand, a reporter for NPR station KCRW in Santa Monica, California, noted that extreme heat is now the most deadly of weather-driven disasters.  She invited GCCA’s Executive Director, Kurt Shickman on her show to talk about the urban heat island effect, and Kurt explained how cool roofs can help cities cool down, conserve energy and save lives.  Kurt noted the many affordable color options available in today’s roofing marketplace.

They also discussed the new regulations in Los Angeles, which require white roofs on new commercial and residential buildings, as well as major roof rebuilds.

You can listen to the show here, and read more about efforts to bring down temperatures in Los Angeles with cool roofs,here.

New Cool Roofs Project Takes Off in Seoul, South Korea

Seoul, South Korea launches a new cool roofs initiative with a campaign to help people paint their roofs white, and plans to expand the program next year:

The Seoul city government will soon come up with plans to expand the initiative in stages.  For example, it will begin with pilot projects in a select number of buildings from this year, followed by a bigger program in 2015 that will include financing support to those building owners that implement building retrofit projects.

(This article also gives brief mention to research conducted by GCCA Board Member, Hashem Akbari.)