Fields of wind turbines and homes with shiny solar panels on their roofs have become part of the natural landscape in many areas today, but the notion of harnessing renewable sources of energy from Mother Nature is far from new. As early as 200 B.C., wind-powered water pumps were being used in China, and windmills were grinding grain in Persia and the Middle East. Thousands of wind pumps were installed by homesteaders and ranchers settling in the western United States, while the Dutch used them to drain lakes and marshes. Now in the 21st century, renewable energy is in the spotlight as the solution to rising costs of oil and gas, finite supplies of fossil fuels, and increasing environmental concerns.
Semiconductors are powering some of these energy solutions, with devices such as MOSFETs (metal-oxide semiconductor field-effect transistor), IGBTs (insulated gate bipolar transistor), DSPs (digital signal processor), MCUs (microcontroller), and the use of SiC (silicon carbide) compound and discrete circuits in green technology products. In recognition of Earth Day, coming up on April 22, here are some ways our industry is supporting renewable energy.
The global wind energy market was estimated at nearly $143 billion in 2014 and is forecasted to reach ~$300 billion by 2022. In fact, one of the world’s largest information technology companies has even invested in a wind project to power its data center. Wind turbines use semiconductors to convert power and couple the generator with the grid. Output from the turbine is converted to DC power by an AC/DC converter, and then converted to commercial frequency AC power through an inverter. However, offshore environments are particularly harsh, and the technology has to handle exposure to salt, humidity, and other natural elements. Semiconductors also have a role to play in managing grid stability, which is impacted by the intermittent nature of wind.
Solar has been experiencing rapid growth: new solar capacity rose 50% in 2016, led by the U.S. and China. Solar energy is generated when light is converted to electricity, known as the photovoltaic effect. This process requires a light-sensitive material, so solar panels use highly processed silicon. Techniques for making microprocessors have been used to increase efficiency of solar cells. A France-based company created a cell with an efficiency of 46%, converting more than twice as much sunlight into electricity as conventional cells. Solar inverter systems (DC/AC) and converter systems (DC/DC) use microcontrollers to maximize the power production from solar panels, as well as converting low voltages into usable higher voltages.
Equipment in the renewable energy industry is being maintained in new ways, made possible by semiconductors. Drones are being used for wind-turbine inspections, supplementing ground observation, cutting costs, and reducing risks for inspectors. Drones equipped with high-definition and thermal imaging cameras are also being used to carry out aerial inspections of solar panels, while in Japan, autonomous robots are being used to clean them.
We’ll continue to see increasing investment in alternative energy sources, with the share of renewable energy in global power generation predicted to increase from 22% in 2013 to more than 26% in 2020. China alone is expected to account for ~40% of renewable energy capacity growth, while Saudi Arabia is planning to pour tens of billions of dollars into renewable energy by 2023. As we continue to harness all this natural power, Mother Nature will be helping us to keep our planet green in more ways than one.