21-08-2018 | By Christian Cawley
Solar power usage is on the rise, but remains a small portion of the renewables vertical. In 2015, 23% of all Chinese power was generated with from renewable sources; in Germany, 12.4%. By contrast, the USA managed just 10%, and of all of these, only a small proportion came from solar power.
This, despite vast areas of suitable, solar-friendly real estate, in each country.
Solar power made gains in 2017, and considerable growth is expected by 2022.
This is largely due to existing solar technology, with mass production enabling larger solar farms. But is it an efficient use of real estate for a technology that has struggled to catch the public imagination?
Perhaps the problem isn't with the amount of solar panels, or the size of the solar farms. Simple efficiencies can be introduced into the production of solar power that could radically increase the amount of clean energy available.
Keep Pushing the Shockley-Queisser Limit New Technology
For many years, solar power technology was hamstrung by the Shockley-Queisser Limit, the theoretical maximum efficiency of a photovoltaic cell. Like Moore's Law in microprocessor development, it would take box breaking imagination to think a way around the limit (which was nevertheless based on some incorrect assumptions).
Several attempts have been made to break the limit. For instance, tandem cells overcome problems found within single cell solar panels; they're currently used to power orbital satellites.
Meanwhile, sunlight intensity can be altered with mirrors and lenses; too much concentration, however, and any efficiencies found can be reduced due to additional heat. Other options for hardware efficiency at the solar cell level include increasing the number of photons that can be absorbed.
Better Infrastructure For Solar Power
On a more practical level, are national electrical infrastructures suitable for solar power? This is a hearts-and-minds scenario. Delivering clearly-labeled solar power to businesses and homes will change the public perception, and raise expectations. Clean air, cleaner cities, and a society existing without yet another reason for cultural guilt; all potential benefits.
At a metropolitan level, offering car recharge points (or even laptop/smartphone/tablet stations) powered by solar generated electricity can display a city's commitment to green policies.
Schematics of a grid-connected residential PV power system. By S-kei - Own work, CC0, Link
Send Solar Power Back to the Grid
Solar power storage was long thought to be the most efficient use of "waste" power. However, a study by the University of Texas determined that solar power storage increases energy consumption (by 324 to 591 kW-hrs), rater than lower it.
While a cleaner solution, excess energy would be better being sent back to the grid. The problem here, however, is that the infrastructure isn't in place for such Grid Inter-tie arrangements.
Solar Tracking Panels
Staring at the sun is no good for anybody; except solar panels, that is. But their arrangement has for a long time been based on static positioning to deal with the arc of the sun across the sky. The result is numerous banks of panels in a single field positioned to capture the optimum sunlight at different times of the day.
This is inefficient.
The technology exists to construct motorized solar panels that "track" the sun. Whereas three panel arrays might have been used to capture light at different times of the day (morning, noon, and afternoon), tracking panels can collect the optimum solar power throughout the day. Power requirement is minimal, and the efficiencies considerable.
The technology exists to push solar power as a viable option for mass produced, clean energy. Making it efficient, and reliable, can only result in solar power being demanded by industry and the public alike.
Read more electronics news related to solar power technology : Solar micro inverter market strengthens on PV demand – NEC