‘Green’ Lighting System Achieves Energy Savings With Help From ACRYLITE PLUS®
In a society that is witnessing an evolution of environmental and economical consciousness, innovative American designers are tasked with creating new products that not only solve the practical needs of the consumer, but also the requirements of the “green” movement. This all-encompassing initiative has caused manufacturers, architects, and builders to reevaluate space-illumination techniques so that natural light can extend to areas that previously required artificial light. One company helping to lead the green charge is Solatube International, which uses a high-performance acrylic polymer from Evonik Cyro as part of its systems that naturally light any room in a commercial building or residential home.
When the company opened its doors in Vista California, it had a goal of developing a solution to bring daylight to dark places that had never had access to natural light. This would allow homeowners and businesses to create natural interior lighting during the daytime hours, and in turn, conserve energy and save money.
The company designed Solatube Daylight Systems. Regardless of location in a building, a tube fitted with a highly-reflective material that redirects sunlight from the exterior to the interior is installed. On the outside, a dome connected to the end of the tube channels light through it down the reflective system. At the ceiling level of the structure, a diffuser—resembling a recessed light fixture—spreads light evenly throughout the room.
Developing such a system didn’t come without its challenges. One was selecting the proper material for the dome.
Choosing the right acrylic resin
In order for the system to function at its optimal potential, the dome material had to block UV radiation from entering the tube, transmit visible wavelengths, provide impact resistance, have a high melt flow index for molding prismatic patterns in the dome, and be cost-effective so the system could be a money-saving alternative to standard bulbs and fixtures.
“The resin was critical to the overall design,” said Paul Jaster, director of R&D, product development, and technical at Solatube. “If the dome doesn’t allow enough light through, the system doesn’t work. If it doesn’t block enough UV radiation, the system doesn’t work. If it’s not resistant enough to damage, the system doesn’t work. It was a tall order, but necessary.”
High design requirements created an opportunity for Solatube to work with Evonik Cyro, a company it had heard good things about but didn’t have any firsthand knowledge.
“We knew about Evonik Cyro, but had never done business with them before. They were very cooperative during the selection process,” said Jaster. “Their laboratory provided a number of acrylic resin samples to our molders so we could determine the best product for our needs. Evonik Cyro also shared the cost to have this special resin weather tested for various compliance requirements.”
That kind of support and commitment extended around the globe. In addition to providing technical assistance to ensure Solatube products became certified in the United States, Evonik Cyro offered Solatube a logistical and domestic solution to supplying its Chinese manufacturing facility. No other supplier had the capacity to do so, and it was a critical factor in Solatube’s decision.
The choice after the selection process was ACRYLITE PLUS® impact acrylic polymers. The acrylic polymers are specially formulated to offer enhanced impact resistance, toughness, UV absorption, and chemical resistance, without sacrificing clarity. They combine maximum impact performance with the clarity expected from a standard poly methyl methacrylate (PMMA) material. The compounds resist the dverse effects of outdoor weathering, retaining both physical properties and appearance after long periods of outdoor exposure. In short, ACRYLITE PLUS® met all the criteria.
The polymers were available in a number of grades that varied according to comonomer content, molecular weight, lubricant content and rubber modified content. Regardless of what Solatube needed, there was an ACRYLITE PLUS polymer grade that provided the optimum balance of impact resistance and melt flow. In the end, ACRYLITE PLUS® zk5BR clear and white were selected for the dome.
“Even after we made our selection and had moved on to fabrication, Evonik Cyro continued to be helpful throughout the process. The relationship has worked out well, and we are satisfied with the results,” said Jaster.
In the end, the Solatube system achieved the requirements of the design: the dome and light tube allow maximum light through while keeping harmful UV rays out, they are naturally resistant to damage, and—most important to the end-consumer—is cost effective.
The Solatube Daylight System is a smart alternative to skylights, according to Jaster. They offer flexible location options, low installation cost, and better lighting performance because it doesn’t use a skylight well, in which light is lost through absorption into the drywall shaft. The system captures light more effectively on the rooftop, with the help of the domes made from ACRYLITE PLUS®, and efficiently transfers more of it down the reflective tube and into the room. The system has insignificant heat gain, so air conditioning or heating are not affected.
“The Solatube Daylight System has a payback period of about five years based on displaced electricity from lighting and air conditioning loads. ACYLITE PLUS has gone a long way in helping us achieve these results,” said Jaster. “Everything about the process, from finding a material, to fabrication, to seeing the final product installed has been great so far.”
Evonik Cyro LLC
Evonik Cyro is an Evonik Degussa Corporation group company. Headquartered in Parsippany, NJ, Evonik CYRO is a leading manufacturer of acrylic sheet and molding compounds, and bulk and performance monomers. Evonik Cyro manufactures and markets its acrylic molding compounds under the ACRYLITE® trade name in the Americas. These same products are manufactured and marketed under the PLEXIGLAS® trade name on the European, Asian, African and Australian continents.
Evonik Industries is the creative industrial group from Germany which operates in three business areas: Chemicals, Energy and Real Estate. Evonik is a global leader in specialty chemicals, an expert in power generation from hard coal and renewable energies, and one of the largest private residential real estate companies in Germany. Our strengths are creativity, specialization, continuous self-renewal, and reliability. Evonik is active in over 100 countries around the world. In its fiscal year 2007 about 43,000 employees generated sales of about €14.4 billion and an operating profit (EBITDA) of more than €2.2 billion.
In so far as forecasts or expectations are expressed in this press release or where our statements concern the future, these forecasts, expectations or statements may involve known or unknown risks and uncertainties. Actual results or developments may vary, depending on changes in the operating environment. Neither Evonik Industries AG nor its group companies assume an obligation to update the forecasts, expectations or statements contained in this release.