Researchers have discovered that a mineral known to science for over a century has great potential for solar power applications. Perovskite, which is an abundant mineral first discovered in the Ural Mountains of Russia in the mid 19th century, is said to be very efficient at absorbing light and uses less material to capture the same amount of energy when compared to conventional solar absorbers.
At present there is a duality between cheap and efficient solar power. The most common form of solar cells are silicon based and cost as little as 75 cents per watt. While Gallium arsenide has the highest recorded efficiency of 44%, the metal’s cost can be as high as $1200 for one kilogram. For solar cells to be competitive with fossil fuels, the price has to drop to 50 cents per watt. Using perovskite as a stand in could drop the price of a solar cell to only 10 to 20 cents per watt, while using less material than silicon.
Perovskite-based solar cells will be cheaper because processing this material is so much simpler than processing silicon. It’s only necessary to spread the perovskite pigment onto glass or metal and then join it to the substrate to allow for the movement of electrons, whereas making silicon solar cells is more involved. To date the best achievement in efficiency is 15% but that number is expected to increase.
The cost of silicon is dropping and is expected to reach 25 cents per watt in the coming decade. So it is now a race between silicon solar cells and perovskite solar cells to see which will achieve the most cost to power efficiency. After that, the next step might be to produce the envisioned spray on solar cell.