Energy Generation

Advanced Space Solar Cells:

Solar panels powering orbital satellite and habitat missions must be able to produce the necessary power for the spacecraft over the entire life of the mission, which can be longer than 15 years. The radiation-induced degradation of space solar arrays can be reduced by employing high efficiency InGaN multijunction (MJ) cells in place of crystalline silicon or III-V double-junction (DJ) technologies.  An optimized DJ InGaN solar cell could deliver better than 30% air mass zero (AM0) efficiency, while a triple-junction (TJ) InGaN cell could work at efficiency greater than 37%.  Both cells would degrade less over the life of the orbital mission, resulting in a higher end-of-life (EOL) performance than competing technologies.

A separate specialized application for NASA would be the use of InGaN solar cells for monitoring spacecrafts sent close to the sun, where operating conditions can be as high as 250 ºC and non-operation thermal exposure as high as (300-350) ºC. These are substantially higher temperatures than for typical As-based cells, which can only be operated at 120 ºC and whose exposure limit is (180-200) ºC due to arsenic desorption and dopant diffusion.  By using InGaN PV technology, the additional weight and complexity of panel cooling could be greatly reduced or eliminated.

Enhanced Terrestrial Solar Cells:

An InGaN single-junction (SJ) cell can be physically combined with a silicon SJ cell to produce a tandem double-junction, with two terminal cell, whose processing and packaging would be compatible with existing Si PV fabrication technology.  An optimized InGaN-Si DJ cell is projected to have an efficiency of 35% or higher, which is 1.40X–1.75X greater than peak SJ silicon cell efficiencies. Under concentration, this DJ efficiency would rise to better than 40%.

The same MJ cells developed for space applications can also be planned for use in a terrestrial environment, being especially suited for deployment in concentrator arrays with values exceeding 100X.  Efficiencies exceeding 45% are projected for triple-junction InGaN solar cells, which are under construction.

Hydrogen Generation:

(Under construction)