PowiGaN Proves Its Value in Extreme Solar Challenge
At the heart of Silvretta — aCentauri Solar Racing‘s solar-powered challenger car entry in the grueling 3,022-kilometer Bridgestone World Solar Challenge (BWSC) across the Australian Outback — is a power electronics circuit using PowiGaN gallium nitride (GaN) technology from Power Integrations.
The aCentauri team calculated that the device saves up to 60 watt-hours of energy, enough to drive the car for 5 kilometers in the dark. With teams fighting for every percentage point of efficiency, this DC-DC converter’s performance — measured at more than 95% at 20% load (where it operated most of the time) — was a important advantage.
The World Solar Challenge is a proving ground for new technologies. While solar cells, batteries and aerodynamics are obvious priorities, aCentauri’s decision to focus on power electronics was just as critical. The team powered its control board — responsible for critical battery monitoring and telemetry — with a flyback converter IC from Power Integrations. The automotive-qualified InnoSwitch3-AQ IC uses a GaN switch instead of traditional silicon.
GaN is a relatively recent entrant in power electronics. A decade ago, it was reserved for ultra-high-performance systems. Power Integrations helped bring GaN to mass-produced consumer products. Analyst firm Yole Group calls Power Integrations the world’s largest supplier of GaN ICs.
Today, GaN dominates the low-power charger market from 30 to 240 watts, outperforming superjunction MOSFETs with negligible switching losses and exceptionally low resistance. This enables higher power density, smaller device sizes and easier thermal management. While MOSFETs remain cheaper at the component level, GaN is often more cost-effective when system design, cooling and efficiency are considered.
GaN is also scaling to higher power levels, from 500 watts to 10 kilowatts. Applications include e-bike chargers, refrigerators, HVAC compressors, washing machines, solar power systems, automotive on-board chargers, lead-acid battery replacements and server power supplies.
Power Integrations’ PowiGaN technology stands out for its higher voltage range. While most GaN technologies are limited to 750 volts, PowiGaN devices are available up to 1,700 volts, supporting flyback configurations with nominal input voltages of 1,000 VDC.
Power Integrations offers complete IC solutions and uses whichever technology — GaN, silicon carbide (SiC) or superjunction MOSFETs — best fits the application. PI expects GaN to dominate a significant portion of the power electronics sector, from about 20 watts up to several hundred kilowatts.
PowiGaN has also demonstrated exceptional reliability, with a calculated failure rate of 0.91 FIT — better than required by the automotive industry — and has a mean time between failure (MTBF) rating of more than 1 billion hours across 14 product families.
That reliability was critical in Australia. In 2023, Team aCentauri finished the BWSC with just 15 minutes to spare before the final stage closed, averaging 61.4 km/h. After four days of competition in 2025, Silvretta improved the average speed by more than 10 km/h.
By registering online, solar race car teams can get a free ($50 value) reference design kit (RDK-85SLR) inspired by the Silvretta DC-DC converter that includes everything needed to create a 46-watt power supply that delivers up to 80 watts for short periods.
This Mr. Green blog is part of our special coverage of Bridgestone World Solar Challenge 2025 as our #PowiGaNVan chronicles Team αCentauri’s journey through the Australian Outback. Follow #PowiGaNVan on Power Integrations’ official YouTube Channel and LinkedIn Page.
