Generating electricity from sunlight bouncing off the ground, working at night, and even helping to grow strawberries: solar panel technology is evolving rapidly as costs for a key segment of the world’s energy transition fall.
The International Energy Agency says solar power needs to be expanded significantly this decade to meet the Paris climate target of limiting temperature rise to 1.5 degrees Celsius above pre-industrial levels.
The good news is that costs have come down drastically.
In a report on solutions earlier this year, the Intergovernmental Panel on Climate Change said the cost per solar unit fell 85 percent between 2010 and 2019, while the cost of wind power fell 55 percent.
“There are some claims that this is the cheapest way humans have ever been able to generate electricity on a large scale,” said Gregory Nemet, a professor at the University of Wisconsin-Madison and lead author of this report.
Experts hope high fossil fuel prices and energy security fears caused by Russia’s invasion of Ukraine will accelerate renewable energy deployment.
The ambitious US climate law, which earmarks $370 billion for efforts to reduce greenhouse gas emissions by 40 percent by 2030, picked up momentum on Sunday.
An analysis by Princeton University experts estimates that the bill could add five times as much solar power in 2025 as it did in 2020.
Nemet said solar power alone could plausibly account for half of the world’s electricity system by mid-century, although he cautioned against looking for “silver bullets.”
“I think there’s really great potential,” he told AFP.
– Rapid changes –
The “photovoltaic effect” – the process by which solar cells convert sunlight into electrical energy – was first discovered in 1839 by French physicist Edmond Becquerel.
After decades of innovation, silicon-based solar cell development began in the United States in the 1950s, with the world’s first solar-powered satellite being launched in 1958.
The IPCC said of all energy technologies so far, small ones like solar and batteries have improved and been adopted faster than bulkier options like nuclear.
Today almost all the panels that gleam on rooftops and spread across vast fields are made in China from silicon semiconductors.
But technology is changing rapidly.
In a recent report, the IEA said these new solar cells convert light into energy one-fifth more efficiently than standard panels installed just four or five years ago.
There are also a variety of new materials and hybrid cells that experts expect could increase efficiency.
These include cheap, efficient, and lightweight “thin film” technologies, such as those using perovskites that can be printed from inks.
Experts say they raise the prospect of dramatic expansion where solar energy can be harvested — if they can be made durable enough to withstand a few decades of use.
Recent research has raised hopes that this might be possible.
In a study published in April in the journal Science, scientists added metal-containing materials to perovskite cells, making them more stable and efficient than traditional silicon models.
Other research mixes materials for different purposes.
A study in Nature used ‘tandem’ models with perovskite semiconductors to absorb near-infrared light in the solar spectrum, while a carbon-based organic material absorbed ultraviolet and visible parts of the light.
And what happens after sunset?
Stanford researchers said this year they made a solar cell that could harvest energy overnight by harnessing heat escaping from Earth back into space.
“I think there’s a lot of creativity in this industry,” said Ron Schoff, who leads research on renewable energy and fleet technologies at the Electric Power Research Institute.
– place, place –
Generating more energy from each panel is becoming increasingly important as solar power is adopted at greater scale, raising concerns about land use and damage to ecosystems.
According to Schoff, an efficiency-enhancing design that’s gaining popularity in large-scale projects is the “bifacial” solar array.
These double-sided units not only absorb energy directly from the sun’s rays, but also from the light reflected from the ground below.
Other solutions involve using the same space for multiple purposes – like semi-transparent solar panels used as a canopy for strawberry plants or other crops.
India pioneered the use of solar panels over ducts a decade ago to reduce evaporation in electricity generation.
Scientists in California have said the drought-stricken US state could save around 63 billion gallons if it shaded its canals.
The construction of a pilot project is to start before the end of this year.
– All shapes, sizes –
Experts say solar power will be part of a mix of energy options, with different technologies better suited to different places.
Schoff said that energy grids with more than 25 percent solar and wind power ultimately need ways to store energy — with batteries or large-scale systems using things like pumped water or compressed air.
Consumers can also do their part, Nemet said, by shifting their energy consumption towards more daytime hours or even hosting their own Airbnb-style solar grids.
He said solar’s modular nature means it can be rolled out in developing countries with sparse access to traditional grids.
“You could have solar on something as small as a watch and something as big as the largest power plants in the world,” he said.
“I think that’s what excites people about it.”
#rise #solar #energy
