Researchers Develop New Solar Technique


Earlier this year, researchers from the University of Arizona reportedly developed an innovative technique to capture the unused solar energy that illuminates a solar panel.

Typically, solar modules are comprised of assembled cells on a rigid panel which are connected to one another, sealed, and covered by a protective glass covering. While a solar cell will work most efficiently when completely covered by photocells in certain colors of light, some panel area is needed to connect the cells properly, leaving potential space where a solar cell shape might not allow those areas to collect sunlight.

This ultimately effects the efficiency of a solar panel, where capturing as much sunlight as possible is critical in harnessing solar energy.

Designed by Ph.D. student Jianbo Zhao, under the supervision of Raymond K. Kostuk, professor of electrical and computer engineering and optical sciences, and in collaboration with fellow Ph.D. student Benjamin Chrysler, the AZI research team was reported to have developed special holograms to enhance solar panel efficiency and maximize the amount of solar energy gathered.

Solar Innovation

Reported to be easily inserted into solar panel packages, the research team have created special holograms capable of separating the colors of sunlight and directing them to the solar cells within the solar panel.

By combining a low-cost holographic optical element with a diffuser, the holographic light collector is situated symmetrically at the center of the photovoltaic module to obtain the maximum effective light collection.

The panel addition is reported to increase the amount of solar energy converted by the solar panel over the course of a year by about 5%, reducing both the cost and number of solar panels requires to power a home, a city or country.

The team computed the annual energy yield improvement for Tucson, Arizona, and presented a reproducible method for evaluating the power collection efficiency of the holographic light collector as a function of the sun angles at different times of day, in different seasons, and at different geographical locations.

“The enhancement of approximately five percent in annual yield of solar energy enabled by this technique could have large impact when scaled to even a small fraction of the hundreds of gigawatts of photovoltaics being installed globally,” said PE Editor-in-Chief Sean Shaheen at University of Colorado Boulder.

“Professor Kostuk’s team has demonstrated their holographic approach with a low-cost material based on gelatin, which is readily manufactured in large quantity. And while gelatin is normally derived from animal collagen, progress in lab-derived versions has made it likely that synthetic alternatives could be used at scale.”

The team’s research findings have since been published in the Journal of Photonics for Energy (JPE).

The research was supported by the QESST Engineering Research Center, which is sponsored by the US National Science Foundation and US Department of Energy to address the challenge of transforming electricity generation to sustainably meet growing demands for energy.

U.S. Solar

An independent statistics and analysis report released by U.S. Energy Information Administration recently found that large-scale U.S. solar capacity growth is expected to exceed wind growth for the first time in its history.

The Short-Term Energy Outlook document, which was released on July 7, projects that solar photovoltaic generating energy will surpass wind generated energy sometime next year. According to the EIA, the solar capacity growth in the forecast reflects various state and federal policies that support renewable energy.

Over the next 18 months, the EIA predicts that roughly 16 gigawatts of solar photovoltaic generating capacity in the electric power sector will be added in 2021 and that another 17 GW will be added by 2022. In addition, the agency expects that small-scale solar photovoltaic capacity will also increase by roughly 5 GW per year, with residential photovoltaic accounts making up the majority of said increase.

However, these numbers are strongly subjected to the uncertainty related to the ongoing economic recovery from the COVID-19 pandemic. While the increase in economic activity and easing of the COVID-19 pandemic has already contributed to rising energy use, research shows that U.S. gross domestic product declined by 3.5% in 2020 from 2019 levels.

The STEO assumes U.S. GDP will grow by 7.4% in 2021 and by 5.0% in 2022, according to forecasts by IHS Markit.

Also outlined in the report, the EIA foresees and increase of U.S. retail sales of electricity by 2.8% this year, after having fell 3.9% in 2020. The largest forecast increase in electricity consumption is slated to occur in the industrial sector, driven by rising levels of economic output, and is expected to grow by 5.1% in 2021.

Retail sales of electricity to the commercial sector are also predicted to grow, but at a slightly slower pace of 2.1%, as some workers continue working from home instead of in office buildings. Overall, the EIA forecasts that U.S. residential electricity sales will grow by 1.9% in 2021, largely due to colder temperatures experienced in the first quarter as compared to last year, in addition to a hot start to the summer.

The Administration attributes the wind sector’s slowed capacity growth to the expiration of the production tax credit. Previously, the credit was extended through 2020 at the end of 2019 and provided a 2.5 cent/kWh benefit for facilities entering service or spending at least 5% of total estimated project costs through the 2020 calendar year.

New additions of solar and wind generating capacity also support the EIA's forecast that the share of U.S. generation from solar and wind will rise to 15% by 2022 from 11% in 2020.

The EIA concludes that overall, the share of generation from renewable sources is expected to increase from 20% in 2020 to 21% in 2021 and 23% in 2022. The increase is projected to be mostly due to new solar and wind generating capacity expansions in the electric power sector.


Tagged categories: Colleges and Universities; Energy efficiency; NA; North America; Program/Project Management; Quality Control; Research and development; Solar; Solar energy; Solar reflectance

Join the Conversation:

Sign in to our community to add your comments.