Kaneka Corporation, a chemical manufacturer based in Japan, has set a new milestone in solar technology with their record breaking energy efficient solar cell. Although the efficiency rates of solar panels continue on an upward curve, reaching new milestones takes a great deal of research, capital and investment from inside and outside sources. Current solar cells are theorized to have an efficiency rate of 29%, but have a practical efficiency rate closer to 20% in most commercial solar panels. Kaneka announced that it has increased solar cell efficiency to 26.3% with high quality thin-film heterojunction (HJ) technology.

HJ technology is based on the technique of layering of the silicon within the cell to maximize band gaps where electron states cannot exist. This technology is currently used in Panasonic modules, which currently carries some of the most efficient panels in the industry. Kaneka took the HJ technology further and placed low-resistance electrodes towards the rear of the cell to maximize the number of photons that collected inside the cell from the front. The results of this added measure have been recognized by the National Renewable Energy Lab (NREL). In order to be recognized by the NREL, the new technology is rigorously tested in both lab and real world settings, both of which set the bar high and require that milestones be met in order to receive NREL backing.

Kaneka Corporation, although proud of their success, are determined to continue increasing the efficiency of their solar cell technology. They have already determined that the overall efficiency of the cell was reduced by 0.5% due to resistive loss, 1% due to optical loss (the way the cell receives light), and 1.2% due to extrinsic recombination loss (where a free electron recombines with a positively charged hole rather than moving on for current collection). All of which when combined prevented them from reaching the goal of reaching 29% efficiency rate set by what the solar cells are theorized to produce. These small changes to solar panel efficiencies means that homeowners and businesses could enjoy further price drops, higher efficiency from their modules, require fewer panels and so on.

Although 2.7% is considered a relatively small increase, it provides a huge leap in solar technology that is hard won. It is through this research and development to individual solar cells that caused the massive price drop in the early 2000s. This drop-in cost was what gave the solar market the boost it needed to be more widely available and affordable to homeowners and businesses. Kaneka’s goal is to continue growing their cell technology, partnering with Japan’s New Energy and Industrial Technology Development Organization (NEDO) to bring the cost of producing solar cells down to $0.06 per kilowatt hour by the year 2030. This price drop will be welcome to the solar industry, and will continue to make solar panels more affordable to more people. With this affordability, we predict that solar will continue gaining momentum and become more financially available to more homeowners and businesses.