Electrical Efficiency

The team led by General Electric (GE) Global Research will develop a new high-voltage, solid-state Silicon Carbide (SiC) Field–Effect Transistor (FET) charge-balanced device, also known as a “Superjunction.” These devices have become the industry norm in high-voltage Silicon switching devices, because they allow for more efficient switching at higher voltages and frequencies. The team proposes to demonstrate charge balanced SiC devices for the first time.

The University of California, Santa Barbara (UCSB) will develop a new technology for optical communication links. Optical interconnects transfer data by carrying light through optical fibers, and offer higher bandwidths than copper with higher efficiency and, consequently, reduced heat losses. However, short-reach optical interconnects are not widely used because of their higher costs and larger device footprints. Production costs of these interconnects could be reduced by using silicon-based fabrication technologies, but silicon is not suited for fabricating lasers, a key ingredient.

Princeton Optronics will develop a new device architecture for optical interconnect links, which communicate using optical fibers that carry light. The maximum speed and power consumption requirement of data communication lasers have not changed significantly over the last decade, and state-of-the-art commercial technology delivers only 30 Gigabits per second (Gb/s). Increasing this speed has been difficult because the current devices are limited by resistance and capacitance constraints.

The National Renewable Energy Laboratory (NREL) and the University of Colorado (CU) are developing a way to enhance plastic solar cells to capture a larger part of the solar spectrum. Conventional plastic solar cells can be inexpensive to fabricate but do not efficiently convert light into electricity. NREL is designing novel device architecture for plastic solar cells that would enhance the utilization of parts of the solar spectrum for a wide array of plastic solar cell types.

Grid Logic is developing a new type of electrical superconductor that could significantly improve the performance (in $/kA-m) and lower the cost of high-power energy generation, transmission, and distribution. Grid Logic is using a new manufacturing technique to coat very fine particles of superconducting material with an extremely thin layer—less than 1/1,000 the width of a human hair—of a low-cost metal composite.

Delphi Automotive Systems is developing power converters that are smaller and more energy efficient, reliable, and cost-effective than current power converters. Power converters rely on power transistors which act like a very precisely controlled on-off switch, controlling the electrical energy flowing through an electrical circuit. Most power transistors today use silicon (Si) semiconductors. However, Delphi is using semiconductors made with a thin layer of gallium-nitride (GaN) applied on top of the more conventional Si material.

Phononic Devices is working to recapture waste heat and convert it into usable electric power. To do this, the company is using thermoelectric devices, which are made from advanced semiconductor materials that convert heat into electricity or actively remove heat for refrigeration and cooling purposes. Thermoelectric devices resemble computer chips, and they manage heat by manipulating the direction of electrons at the nanoscale. These devices aren't new, but they are currently too inefficient and expensive for widespread use.

The University of Nebraska, Lincoln (UNL) will develop an innovative concept for an electromagnetic induction-based static power converter for AC to AC electrical conversions. Their method will use a new device, the magnetic flux valve, to actively control the magnetic flux of the converter. The voltages induced across the device can be controlled by varying the magnetic fluxes. By synthesizing the induced voltages appropriately, the converter can take an AC input and generate an AC output with controllable amplitude, frequency, and waveform.

The University of Colorado, Boulder (CU-Boulder) proposes to develop a capacitive wireless power transfer (WPT) architecture to dynamically charge EVs. Dynamic charging poses serious technical challenges. Transmitters must be connected to the plates in the road while rectifiers and battery charging is integrated with the plates in the vehicle. While energy transfer through the air is efficient, the large distance between the embedded vehicle plates and the road results in a weaker pairing between the two.

Qromis will develop a new type of gallium nitride (GaN) transistor, called a lateral junction field effect transistor (LJFET) and investigate its reliability compared to other types of transistors, such as SiC junction field effect transistors (JFETs) and GaN-based high electron mobility transistors (HEMTs). Qromis' innovative LJFET design distributes and places the peak electric field away from the surface, eliminating a key point of failure that has plagued GaN HEMT devices and prevented them from achieving widespread use.