(Source: ImageOasis - stock.adobe.com)
Green energy is essential in meeting exponentially-rising global energy demand while reducing emissions to curb global temperature rise below 1.5°C1 in the coming decades. The criticality of this energy is driving the renewable energy market toward $2 trillion by 20302, with global energy storage systems (ESS) exceeding $13 billion itself3. And while the costs of green energy could come down by 35 percent for solar and nearly 50 percent for wind by 2030 thanks to the Inflation Reduction Act4, there are still challenges with creating a distributed infrastructure to convert renewable DC power to transmittable AC.
Inverters are the critical technology delivering this DC-AC conversion for green energy sources. And for a good reason: Inverters provide this conversion efficiency of up to 96 percent5. However, challenges exist with inverter technology in both their size and durability at scale despite their clear advantage in power conversion. In addition, the conventional architectures need active cooling and support of the heavy equipment.
To achieve technical performance and commercial success, engineers are converging on an ideal material for large-scale solar and wind inverters: silicon carbide.
Renewable inverters require multiple specification values to ensure the desired performance. Among these are input [DC] current and voltage range, maximum AC power output, conversion efficiency target, and rated operating temperature range for an application.
Once design engineers have quantified these levels, they can design the green energy inverters comprised of building-block components:
Large-scale inverters will be necessary to meet the market demand described above. But inverter technology is not unique to the larger size; there are three primary levels for renewable power conversion:
Silicon has played a critical role in increasing the efficiency of photovoltaic (PV) cells. Currently, the material is also the incumbent solution for MOSFET and IGBT power semiconductors. However, with the exponential demand for renewable energy to reach 2050 decarbonization targets, the current inverter technology is reaching its limits.
Silicon limits the operating voltage, power densities, and temperatures of inverter performance. It also carries switching losses (reducing efficiency), which reduce the capacity of the inverter power supply. The lower efficiency requires a larger size to compensate, increasing the total cost of ownership and carbon footprint.
In contrast, silicon carbide (SiC) is a wide bandgap material that enables substantially higher-voltage operation, power densities, and temperatures. Along with reduced switching and conductive losses and lower-leakage currents than silicon, these advantages increase conversion efficiency. SiC saves 10MW/GW converted and 500W/s in operations for large-scale solar inverter applications, translating to direct energy savings6.
Wolfspeed is well-suited to provide SiC green energy inverter semiconductors, a growing market. With an estimated 60 percent market share and revenues projected to grow from $700 million in FY2022 to $1.5 billion in 20247, the ceiling is very high for the market leader in a technology that comprises just 5 percent of the power semiconductor market at present.
Using a Wolfspeed Silicon Carbide MOSFET like the 1700V SiC Schottky Diode enables a lighter, smaller, and more efficient solar inverter. These advantages deliver fewer system losses, improve efficiency, and lower overall cost per watt compared with traditional silicon by reducing system part count.
In partnership with other renewable systems, solar power inverters and energy storage system (ESS)applications are updating grid power to improve resilience, meet high-current global energy requirements, and reduce their overall carbon footprint. These systems must be as energy and spatially-efficient as possible in rugged climates while remaining cost-effective.
Silicon was instrumental in improving the energy conversion efficiency of early PV panels and has been the incumbent power semiconductor material for over half a century. But with the increasing demands for renewable energy, particularly solar and wind, silicon is reaching its practical limit.
Silicon Carbide solutions address the needs and challenges of renewable energy systems containing semiconductors by delivering increased power density, reducing switching losses, and increasing switching frequency. Wolfspeed Silicon Carbide solutions enable more compact, lightweight, and efficient inverters for solar power semiconductors that convert sunlight to electricity in rugged environments with varying temperatures, high humidity, and other harsh conditions.
Adam Kimmel has nearly 20 years as a practicing engineer, R&D manager, and engineering content writer. He creates white papers, website copy, case studies, and blog posts in vertical markets including automotive, industrial/manufacturing, technology, and electronics. Adam has degrees in chemical and mechanical engineering and is the founder and principal at ASK Consulting Solutions, LLC, an engineering and technology content writing firm.
Wolfspeed is a leader in the worldwide adoption of Silicon Carbide and GaN technologies. Wolfspeed provides industry-leading solutions for efficient energy consumption and a sustainable future. Wolfspeed’s product families include Silicon Carbide materials, power-switching devices, and RF devices targeted for various applications, such as electric vehicles, fast charging, 5G, renewable energy and storage, and aerospace and defense.