Spraying a new “green” solution on glass surfaces helps to cut temperatures and save on air conditioner use.
The need to address radiant heat coming through glass in high-rise buildings and even in motor cars has long been a thorny issue, made more important in recent times by rising costs of the electricity or petrol needed to power air conditioners.
In Vietnam, with its hot and humid climate coupled together with these concerns, finding temperature-resistant solutions has become a pressing need. There are many ways to reduce temperatures in buildings and cars apart from air conditioning, such as heat-resistant film and even the humble curtain.
But these fail to fully address the problem. Recent research on a solution containing Nano TiO2, by Dr Pham Van Nho from the Faculty of Physics at the Hanoi University of Science under the Vietnam National University, may well make many of the problems easier to resolve.
“Green” solution is a name of a type of liquid solution containing Nano TiO2. In explaining why it is called a “green” solution, Dr Nho said that it is non-toxic and uses sunlight to decompose toxic chemicals, bacteria and viruses. In order to improve the quality of the solution so that it can truly be called “green”, it must also be produced with cheap and simple technology, be excellent in quality and have an adhesive form. “I believe our product is completely a ‘green’ solution,” Dr Nho said.
After spraying the solution on glass or walls, it dries within five seconds and forms a cohesive transparent film that reflects sunlight away, making interiors much cooler. The solution also forms a self-cleaning surface and keeps glass clean and bright.
Tests at the laboratory of the Applied Physics Department at Hanoi University of Science show that, after using the Nano TiO2 solution, temperatures fell 5 to 10 degrees Celsius. And when sprayed directly on walls in a closet, the “green” solution also had an anti-bacterial function, deodorising and creating self-cleaning and anti-fungal coatings.
According to the Dr Nho, with the solution being anti-bacteria and anti-virus it is now being sold at $250 per litre, but the cost will come down to half or even less when large quantities are produced and economies of scale come into play.
He added that dozens of litres of the “green” solution can be produced in one day and that one litre can be used on approximately 20 sq m. He has already been approached by architects hoping to use it in their projects. “The extraordinary thing is that the ‘green’ solution lasts virtually forever if it is not touched after being applied,” he said.