Lighting up roads with streetlamps costs a lot of money and requires a lot of electricity, so scientists from Michoacan’s University of San Nicolas Hidalgo (UMSNH) in Mexico have come up with a better solution.

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They’ve invented a type of light-emitting cement that can absorb solar energy during the day and release it back into the environment at night, thereby lighting up roads, highways and bicycle lanes naturally.

The researchers say that most fluorescent materials being used today are made of plastic, and last around 3 years. They claim that this cement will last hundreds of years, and that the intensity of light can be controlled, so that motorists are not blinded by it. As of now, the cement emits blue or green coloured light.

"Nine years ago, when I started the project, I realised there was nothing similar worldwide, and so I started to work on it. The main issue was that cement is an opaque body that doesn't allow light to pass to its interior," said Ph.D. Jose Carlos Rubio, from UMSNH.

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Dr. Rubio explains that common cement is like dust, and when it’s added to water it dissolves like an effervescent pill. “In that moment it starts to become a gel, similar to the one used for hair styling, but much stronger and much more resistant. At the same time, some crystal flakes are formed; these are unwanted sub-products in hardened cement,” he adds.

He and his team of researchers modified the micro-structure of cement in order to get rid of these unwanted crystals so that the cement can form a complete gel-like substance. As a gel, it can absorb solar energy during the day and then release it back into the environment in the form of light over the next 12 hours. Dr. Rubio also says that the cement is ecological, because it is composed of sand, dust or clay, which becomes the gel, and the only residue after the making is steam.

The team has patented the invention and is currently getting a lot of international recognition for their work.