Technology often advances in fits and starts, like when a new car model sports a new dashboard design or a computer runs a little faster with more memory. Sometimes, though, breakthroughs change our perception of what a piece of technology can do for us. Think about the performance jump from a conventional car engine to a fuel-injection system, or the leap in quality from regular DVDs to Blue Ray, or the way the Internet accelerated its usefulness when it moved from dial-up modems to broadband.
Bright future Sharp’s senior engineer Mr. Takamoto tells how he sees
the future of solar energy.
That’s the kind of major advance in solar technology that Sharp announced in October, with profound implications for the planet’s energy future. By inventing compound solar cells that are nearly 14 percent more efficient than previous models (up from 31.5%), Sharp laid claim to the world’s highest* solar cell conversion efficiency - and launched yet another revolution in renewable energy. The potential spin-offs of this solar efficiency boost – from improving orbiting satellites to mass-producing solar electricity on Earth - are breathtaking.
In recent years, solar electricity has expanded rapidly, as technology progresses and the imperative to shift away from fossil fuels becomes more pressing. Today, solar cells that use silicon to convert sunlight into electricity have about 20 percent efficiency (for crystalline panels) and about 15 percent (for thin-film). Sharp has been a leader in improving this type of solar power generation, which has many important terrestrial applications, like rooftop solar. Since 2000, Sharp has also made “compound solar cells” that don’t use silicon. Compound cells are more expensive to manufacture, but their efficiency and reliability make them the obvious choice to power orbiting satellites that observe the earth and provide essential communication links.
Sharp’s achievement of 35.8 percent efficiency on a “triple-junction compound solar cell” paves the way for this solar technology to find additional uses here on Earth. Engineers foresee installing them on airplanes and ships, for starters, and Sharp compound cells recently powered a car to victory in the world solar car race, with a top speed of 123km/h. Looking ahead, compound solar cells will be a key to ramping up utility-scale “concentrated solar” electricity production, in addition to expanding orbiting applications. “We’re moving from space to the ground,” says Tatsuya Takamoto, a senior Sharp engineer who led the compound solar cell development.
It was no surprise to anybody who follows the field that Sharp would once again be leading the solar pack. For 50 years, Sharp has made a series of groundbreaking technological advances, from pioneering solar-powered lighthouses or the first solar-powered calculators. By using new ideas to build on a half-century of innovation, Sharp retains its status as the consistent leader in a burgeoning field. Takamoto says that the new breakthrough took perseverance and confidence that their new approach would yield big results. “We have finally done this,” says Takamoto. “This compound solar cell will make great contributions to the world.”
*As of October 22, 2009, for non-concentrator solar cells at the research level (based on Sharp survey).
