Planet Eureka #05 - Solar energy (without silicon) ... Wooden satellites ... largest Canyon ... Crocodiles
Happy New Year. Welcome to the first edition of the newsletter this year. Wish the new year brings peace and happiness to you and your beloved ones.
Solar energy without silicon? Enter Perovskites
The problem with silicon solar panels
Think solar. Chances are that you cannot imagine any material other than silicon panels. But these silicon based solar panels convert only 22% of solar energy and the efficiency has maxed out.
What is Perovskite?
Perovskite is a Calcium Titanium Oxide (CaTiO3) mineral. It was first discovered in 1839 in Ural mountains by German scientist Gustav Rose who named the mineral after Russian mineralogist Lev Perovski.
How does Perovskite generate electricity?
With sunlight, the photons in the minerals produce excitons (electron-hole pairs). The difference in the exciton binding energy of the perovskite materials produce electricity. Coated with silicon, this has potential to increase the efficiency to nearly 40%.
What are the advantages of Perovskite?
The mineral is abundant and what you need is a thin layer of perovskite, which can be printed using a inkjet printer and can be as thin as a paper. So you can wrap it over buildings, cars or any installations thus saving lots of space. Source link.
Disadvantages of Perovskites
The main issue is degradation over time and exposure to heat, moisture and snow. Plus the material is toxic in nature. But one can hope science can find a way to overcome this. Source link.
Wooden satellites to reduce Space junk?
Space junk is a real problem. There are nearly 6000 satellites in space and 60% of them are junk. Plus, there is a plan to launch 9000 more by 2028. Satellites that have served beyond their lifetime continue to linger in space. Even if the satellites are burnt during reentry, the remnants continue to linger in atmosphere as space junk.
To combat this problem, Japanese scientists have mooted the idea of making satellites of wood. The idea is that wood is easy to carve and can disintegrate quickly while reentering the atmosphere. Also, since wood is largely transparent to radio waves, the problem of unfurling heavy components like antenna and panels can be avoided after entering the orbit.
But critics argue that the components inside the satellite are still not wood and they will continue to pose a problem.
Did you know?
Crocodiles survived the meteor crash that wiped out the dinosaurs. How?
That’s because crocodiles can survive in both land and water for a long period without food. Also, the evolution of crocodile is ‘dead slow’. That’s why you would not not see different types in crocodile family compared to that in a cat family. They have landed in an equilibrium state that does not require them to evolve.
One last thing … Largest canyon in the solar system
NASA's Mars Reconnaissance Orbiter has sent the pictures of Valles Marineris, the largest Canyon in the solar system. The canyon that runs along the equator is 4200 kms long (almost the length of US). Scientists are not sure how the canyon could have been formed, as Mars atmosphere is so hot to support a river that could have cut the canyon over a long period of time.
That’s all for this edition. Stay Healthy, Stay Safe.
Best
-Team Planet Eureka