Solar energy provides a challenge for almost every aspect of electronics. In basic research, small companies license technology from university-based research to add to the efficiency of solar cells and other areas of photovoltaics production. Some companies provide turnkey manufacturing, marketing, and development for customers entering the solar industry. I toured one such company, GT Solar, to see how they’ve helped improve solar electronics.
Small companies, such as San Jose-based startup Solexant, have licensed materials technology from university-based research to add to the efficiency of solar cells. Solexant licensed materials technology from an advancement under development at a photonics institute at the University of Buffalo that can harvest energy from infrared (IR) light to boost the energy of solar cells.
Under the executive director Paras Prasad, the team from the University of Buffalo plans to harvest energy from infrared and ultraviolet (UV) ranges of the spectrum yet untapped by today’s solar cells. Various projects use tunable quantum dots to absorb IR photons and organize them by coupling like charges to carbon nanotube (CNT) walls. Other projects convert 980-nm IR to visible light to be absorbed by a solar cell.
“We recently showed a capability of harvesting 30% of the IR photons going to a photovoltaic cell,” Prasad said. Since raising efficiencies of solar cells is a major issue in reaching “grid parity,” or costs comprable to those of existing power solutions, the various approaches that the joint venture takes attack the problem from many angles.
For newcomers wishing to get into the solar panel production business, companies like GT Solar in Merrimack, NH, offer everything for a practical turnkey solution. GT is able to equip users with the technical, manufacturing, and marketing experience needed to start up and operate a photovoltaic business. “We have experts creating solutions for all three components of the solar value chain: wafer, cell, and module fabrication lines,” said Keith Matthei, VP, equipment sales (Figure 1).
Figure 1. Keith Mathei, GT Solar, offers equipment for production of photovoltaic equipment piecemeal or in a turnkey method.
At the heart of GT’s equipment is the directional solidification system (DSS) furnace that produces a large segment of the world’s multicrystalline silicon ingots (Figure 2). The DSS furnace grows multicrystalline ingots quickly, cooling from the bottom up. GT has expertise in mechanical design, vacuum and high-pressure chambers, control system design, and crystal growth modeling. By collaborating with University Center of Excellence for Photovoltaic Research and Education at Georgia Tech, University of New Hampshire, and other private and research facilities, GT has been able to improve their products.
Figure 2. GT Solar’s Directional Solidification System (DSS) furnace produces a large segment of the world’s multicrystalline silicon ingots.
Even in tough times, companies recognize the value of renewable energy. On February 5, Timex Group USA Inc. held a dedication ceremony for its recently completed installation of 800 solar panels outside its Middlebury, CT, headquarters as one of the largest ground-mounted solar electric units in the northeastern U.S. As part of the $2.5 million project, 27 rows of 244-kW solar panels were installed on the eastern side of the watchmaker’s property. The photovoltaic system is said to generated 285,439 kilowatt hours per year, avoiding release of more than 6.6 million pounds of carbon dioxide, 28,000 pounds of sulfur dioxide and 11,000 pounds of nitrogen oxide over the 25-year lifespan of the system. This clean energy project was financed in part through a $920,000 grant from the Connecticut Clean Energy Fund and tax credits.
Though renewable energy is just now ramping up and getting established in the U.S., the signs of growth can be seen in all areas, from R&D collaboration to practical turnkey assistance, innovative equipment, and current installations.
Gail Flower, editor-at-large