Coatings are utilized for their ability to visually beautify and functionally protect many types of materials such as metals, woods and composites. Recent advances in specialty infrared reflective pigmentation technologies allow the coatings formulator, and thus the original equipment manufacturer or contractor, to impart additional functionality to their products. This functionality enhances the overall value of the products and has the ability to reflect invisible heat energy while achieving a desired visible color. The reflection of heat energy results in a lower temperature substrate when exposed to sunlight. The lower substrate temperature has a direct impact on reducing the cooling load in a building, for example, when used in a roof coating. The higher infrared reflectivity of the substrate results in other benefits such as reduced warpage, reduced thermal cycling, reduced chemical degradation and the improved comfort of people in direct contact with the substrate.
In part one of this three-part series, we will discuss the environmental impact, voluntary organizations and legislative requirements relating to infrared reflective pigmentation technology. In part two of the series, we focus on the science behind infrared reflective pigmentation technology, and in part three of the series the application of the technology will be reviewed.
The majority of commercial and residential electricity is produced by steam-driven turbine generators. Steam can be produced by burning various fossil fuels such as natural gas, coal and oil. Steam is also produced by heating water from nuclear reactions in nuclear power plants. The burning of fossil fuels produces combustion by-products and ultimately emits them into the atmosphere. The atmospheric contaminants produce an unhealthy environmental condition known as smog. A major component of smog is ozone. Decreasing electricity usage by increasing energy efficiency benefits the environment by reducing demand.
Increasing the energy efficiency of a building or structure, be it commercial or residential, will result in a direct and quantifiable benefit to the owners. This increased energy efficiency reduces the amount of energy needed for cooling during peak summer demand, when electricity costs are at a premium. The macro effect of using energy-efficient technologies is a reduction in the electric load delivered by the power grid. This efficiency not only reduces end-user cost, but it also reduces the frequency of blackouts or brownouts, and will reduce the urban heat-island effect that causes ambient temperatures in a highly populated area to well exceed the ambient temperature of the rural surroundings.1 The incorporation of infrared reflective technologies into building products such as aftermarket roof coatings and OEM coil-coated metal roofing products increases the heat reflectance of roofing systems and reduces the amount of heat flowing into the structure. The reduction of heat flow lowers the cooling load and increases the efficiency of the structure.
Additional applications of infrared reflective technology include automotive interior and exterior coatings, specialty marking inks and coatings, thermoplastic coatings, marine coatings, and military applications.
Government Legislation and Organizations
The rising cost and increasing demand for energy continue to drive state and federal government regulation and legislation designed to reduce energy consumption, or at least, reduce the rate of growth of energy consumption. The result is a reduction in the emissions of industrial power plant by-products released into the environment, as well as maintenance of the integrity and continued availability of energy products. Several voluntary programs and mandatory legislation have been created to facilitate this movement towards energy efficiency, such as the Energy Star program, the Leadership in Energy and Environmental Design program, California’s Title 24 legislation, the United States Green Building Council, the Cool Roof Rating Organization, and the Cool Colors Project.
Energy Star and LEED
In 1992, the Environmental Protection Agency (EPA) created a program called Energy Star. Energy Star is a voluntary labeling program created to facilitate monetary and environmental efficiencies through the application of energy-efficient technologies and practices. Energy Star is a highly successful program and highly visible to the consumer.2
In 1996, the EPA partnered with the United States Department of Energy (DOE) and extended the range of applicable products covered by the Energy Star program. Later, the Energy Star label was applied to commercial and residential buildings.2
The Energy Star label exerts a significant buying influence by guiding the consumer to purchase energy-efficient products that improve their quality of life through energy efficiency.
Construction products, specifically roofing products, can also bear the Energy Star label. The proper use of infrared reflective pigmentation technology facilitates the Energy Star rating for exterior roofing products.
The Leadership in Energy and Environmental Design (LEED) is sponsored by the United States Green Building Council (USGBC). The LEED program is a “voluntary, consensus-based national standard for developing high-performance, sustainable buildings”.3 LEED was created to define “green building” by establishing standards, promote holistic building design practices, recognize environmental leadership in the building industry, stimulate energy efficiency competition, raise consumer awareness of “green” building benefits and to transform the building market.”3
LEED standards include new commercial construction, existing building operations, commercial interiors, core and shell projects, homes, and neighborhood development. The LEED standards define a point-based system establishing the performance and environmental sustainability of a building or structure. Among the categories for gaining points are Energy Star-qualified roofing products. Gains in energy efficiency, as simulated by computer models, can generate additional points. Much more information is available on the USGBC website, www.usgbc.org.
The Cool Roof Rating Council is an independent organization created to provide non-biased evaluations of roofing materials with respect to radiative properties. On the Cool Roof Rating Council’s website is a list of rated roofing products and their corresponding solar reflectivity and emissivity ratings.4
California’s Energy Efficiency Standards for Residential and Nonresidential Buildings Title 24
Title 24, Part 6, of the California Code of Regulations specifies the energy efficiency building standards required to “respond to California’s energy crisis to reduce energy bills, increase energy delivery system reliability and contribute to an improved economic condition of the state.”5 In Section 3.4.1 of the commercial building code enacted in 2005, cool roofs are addressed. Cool roofs are defined as roofs that are designed to reflect and emit solar radiation. This section specifies that cool roofs must be tested and labeled by the cool roof rating council. Section 3.4.2 calls for a cool roof in all low-slope roofing applications for non-residential buildings and specifies that a qualifying cool roof must have an initial solar reflectance of 70% or greater and an initial emittance of 0.75 or greater.
Many other state governments are following California’s lead and legislating similar prescriptive requirements for cool roofs. In order to maintain a competitive edge, the exterior coatings manufacturer must consider infrared reflective pigmentation technologies as a part of their market strategy to maintain and grow market share.
The Cool Colors Project
The Cool Colors Project is a consortium of Lawrence Berkeley National Laboratories (LBNL), Oak Ridge National Laboratories (ORNL) and 16 industry partners. The Cool Colors Project pioneered the infrared reflective pigmentation movement in commercial and residential roofing. The Cool Colors Project website contains a wealth of resources to aide and educate the formulator about infrared reflective pigmentation technology and is actively engaged in Title 24 Prescriptive roofing requirements for 2008.6
Demonstrated Energy Savings of Infrared Reflective Technologies
A collaboration among industry suppliers (BASF, Steelscape, Custom-Bilt Metals) and government-funded laboratories (LBNL and ORNL) created a cool roof field study to demonstrate the efficacy of infrared reflective pigmentation technologies. Guided by the collaboration, two schools in Georgia were constructed utilizing the same design with a floor plan layout of 90,000 square feet. The first building, the Baggett School, was constructed with a standard evergreen roof exhibiting a 12% total solar reflectance. The second structure, the Poole School, was constructed with an evergreen roof utilizing infrared pigmentation technologies at 29% total solar reflectance. The first year electric savings of the Poole School utilizing infrared reflective roofing technologies was demonstrated to be $8,803.7
Florida Solar Energy Center Study
In a Florida Solar Energy Center study, seven identical houses were constructed utilizing roofing systems with and without infrared reflective pigmentation technologies in various color spaces. From the study, the white roofing systems yielded an annual 18–26% energy savings at a total solar reflectance range of 66 to 77% versus the control house with a standard dark shingle roof. The terra cotta tile yielded an annual 3–9% energy savings with a total solar reflectance of 34.6% versus the control house. The highly reflective roofing systems showed a 28–35% reduction in peak energy demand versus the control house, and included marketable color for the consumer.8
Infrared reflective pigmentation technologies can be utilized to minimize heat build in objects exposed to sunlight, resulting in local energy efficiencies and physical performance property enhancements, while achieving a visually appealing color.
The macro effect of increasing energy efficiency of structures reduces energy consumption and the negative attributes of consumption such as emissions and energy blackouts.
Voluntary organizations and legislation exist to facilitate the use of infrared reflective pigmentation technology. The energy efficiencies gained by utilizing infrared reflective technologies add value to products incorporating the new pigmentation technologies while saving energy and money.
For more information, contact David M. Hyde, Coatings Process Development Engineer, firstname.lastname@example.org; Benjamin Arnold, Market Development Manager, email@example.com; or Elizabeth Campbell, Product Development Manager, firstname.lastname@example.org.