Imagine if your home was powered by solar balloons that sat above the clouds. Scientists at the Japanese-French Laboratory for Next Generation Photovolatic Cells (NextPV) are aiming to do just that.
Solar cells’ efficiency relies on the proximity of the cells to sunlight. Even if the cells are put directly in the path of sunlight, their efficiency is affected significantly by clouds or terrible weather. On a cloudy day, solar panels can produce less than 30% of the electricity they are designed to. According to electro-chemist Professor Jean-François Guillemoles, “Anywhere above the planet, there are very few clouds at an altitude of 6 km—and none at all at 20 km. Under these conditions, the energy source is five times more abundant than on the ground, and production is entirely predictable. So why not send solar cells up above the clouds, where the sun always shines?”
He proposed that hydrogen-filled polymer balloons fitted with solar cells could be used to increase solar cell efficiency. The researchers would like to float the generators just above the clouds, around 6 kilometers (about 3.7 miles) high and below airplane routes, Guillemoles said. In the long-term the balloons could potentially float even higher, at around 20 kilometers (roughly 12.4 miles) high.The high-altitude polymer balloons could be tethered to the ground or allowed to float free. Electricity would be transmitted to homes using a transmitter or cable and a portion of the energy would be used to create hydrogen from an attached fuel cell. At night, the fuel cell would be used to supply energy and electricity.
“A moored high-altitude balloon of reasonable size could store about 10 days equivalent of its own solar electricity production, which is more than enough to meet energy needs overnight, until production resumes in the morning,” Professor Guillemoles says.
There are
obstacles along the way, including cost (which may affect the degree to which the final product is commercially viable), changes in pressure at high altitudes and safety concerns for pilots flying in the sky that will need to be addressed as well.
The lab is looking to create a prototype as a next step. As Guillemoles notes, “It has the potential to make solar energy more sustainable and faster to deploy at large scale.”
For more information, visit: http://www.liapv.rcast.u-tokyo.ac.jp/NextPV/Home.html