
A simulation of the illuminance of an alleyway at noon at two different times of year, autumn (top) and winter (bottom). The new light-directing panel increases the amount of light that reaches the alleyway, as indicated by the higher amounts of red and yellow in the right-hand images (“with panel”) compared to the left-hand images (“without panel”). Credit: Optics Express.
Optical devices could bring natural light into dark, highly populated areas
In dense, urban centers around the world, many people live and work in dim and narrow streets surrounded by tall buildings that block sunlight. And as the global population continues to rise and buildings are jammed closer together, the darkness will only spread.
To alleviate the problem, Egyptian researchers have developed a corrugated, translucent panel that redirects sunlight onto narrow streets and alleyways. The panel is mounted on rooftops and hung over the edge at an angle, where it spreads sunlight onto the street below. The researchers describe their design in a paper published today in Energy Express, a supplement of The Optical Society’s (OSA) open-access journal Optics Express.
“We expect the device to provide illumination to perform everyday tasks, and improve the quality of light and health conditions in dark areas,” said Amr Safwat, a professor of electronics and communications engineering at Ain Shams University in Cairo, Egypt. These dimly lit areas specifically include narrow streets in developing countries, but Safwat said the new panel could be used in any country as a greener, cheaper, and more pleasant alternative to fluorescent and other artificial light.
While other commercially available window-like devices can redirect light, they are designed for shade and redirecting glare or for brightening a room—not a narrow street. So the researchers decided to create their own design. They wanted a simple way to redistribute natural light without the need for a tracking device that follows the rising and setting sun.
What they came up with is a panel made of polymethyl methacrylate (PMMA), the same acrylic plastic of which Plexiglas is made. The bottom of the panel is smooth while the top is covered in ridges that are based on a sine wave, the mathematical function that describes everything from light to pendulums. The researchers used computer simulations to find the size and shape of the grooves that distribute the most amount of sunlight in a wide range of sun positions all year round, whether it’s high or low in the sky. A sine-wave pattern is also easy to manufacture.
Using simulations of sunlight shining on an alleyway, the researchers found that their panels increased illumination by 200 percent and 400 percent in autumn and winter, respectively, when sunlight is most limited. They also tested a small prototype over a 0.4-meter-by-0.4-meter shaft that is 1.2-meters deep and found that it lit up the area as designed.
The next step, Safwat said, will be to build a full-scale model 10 times bigger to validate their calculations and to test it in a real alleyway. The team then plans to market and commercialize the panel. He estimates that a one-square-meter panel and a frame will cost between $70 and $100.
And that may be a small price to pay for the benefits of sunlight. The lack of sun in urban areas doesn’t just make life gloomy; it can be harmful to your health, Safwat said.
“Research has shown that lack of natural lighting can cause severe physiological problems,” such as serious mood changes, excessive sleeping, loss of energy and depression, Safwat said.
He also noted that using sunlight to illuminate historical places—such as ancient alleyways in Egypt—also helps preserve the authenticity of the site, maintaining its cultural value and historical significance.
The Latest on: Redirecting sunlight
[google_news title=”” keyword=”Redirecting sunlight” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Redirecting sunlight
- ESO telescopes on the aftermath of DART's asteroid impacton March 21, 2023 at 2:59 pm
Using ESO's Very Large Telescope (VLT), two teams of astronomers have observed the aftermath of the collision between NASA's Double Asteroid Redirection Test (DART) spacecraft and the asteroid ...
- Observing The Aftermath Of DART’s Asteroid Impacton March 21, 2023 at 1:53 pm
Using ESO’s Very Large Telescope teams have observed the aftermath of the collision between NASA’s DART spacecraft and the asteroid.
- Why scientists are studying the clouds of debris left in DART’s wakeon March 21, 2023 at 7:00 am
Researchers use high-tech instruments to study the dust left from the asteroid deflection test to learn more about our solar system.
- Las Vegas Sun - Homepageon March 20, 2023 at 5:00 pm
Nevada lawmakers are considering dialing back restorative justice student discipline systems to make it easier to remove violent and disruptive children from classrooms. Assembly Bill 285 does not ...
- The New York Sunon March 20, 2023 at 5:00 pm
The House Oversight Committee says Hallie received $35,000 in payments linked to China. In a repeat of the Cold War’s domino effect, Honduras is the latest to fall and Paraguay is teetering. A display ...
- Las Vegas Sun - Homepageon March 20, 2023 at 5:00 pm
Clark County School District Police Chief Mike Blackeye will testify about departmental policies at a joint hearing Wednesday of the Nevada Senate Education and Judiciary Committees. The hearing ...
- Dead by Daylight codes for March 2023on March 20, 2023 at 5:04 am
20th March 2023: We checked for new DBD codes. Behaviour Interactive issues Dead by Daylight codes on a fairly regular basis, and that’s a good thing. Dead by Daylight codes usually give you ...
- Sunlight Financial of Charlotte faces new hurdles from Silicon Valley Bank's failureon March 20, 2023 at 3:59 am
Already cash-strapped Sunlight Financial Holdings Inc. has hit another big bump as a result of its relationship with the failed Silicon Valley Bank. The Charlotte-based financer of solar ...
- Sun Life Financialon March 19, 2023 at 5:00 pm
Sun Life Financial, Inc. is a holding company. The firm engages in the provision of financial services. It operates through the following segments: Sun Life Financial Canada, Sun Life Financial ...
- I’m a building expert – a £10 item can help prevent damp and mould in your homeon March 19, 2023 at 1:52 am
IF you’ve noticed mould growing inside your house, a blocked gutter outside may be part of the problem. If debris has built up, water could be running down the side of your home and ...
via Bing News