Edgar Lim, Vice President, Technology and Procurement, EnterSolar
According to a recent market report by the Solar Energy Industry Association and Wood Mackenzie, the U.S solar market surpassed 2 million installations in Q1 2019 - just three years after the market surpassed the 1 million installation milestone. The industry is projected to continue growing at an accelerated pace and hit 3 million installations in 2021.
"As Moore’s Law revolutionized the electronics industry, a similar effect is taking place within solar"
Innovation is one of the major catalysts for the rapid growth of the industry as technological advancements help increase the efficiency of major equipment, drive down costs and more importantly, improve the operational safety of solar systems.
Solar modules and inverters are some of the major components of commercial solar systems that have undergone significant innovation and advancements over the past decade. This is partly due to the fact that global R&D funding has been increasing year over year. PV Tech Magazine reported more than US$2.0 billion in total research spending over the past two years by the top 21 solar module manufacturers.
The typical solar module used on commercial systems 5 years ago averaged about 300 watts but the workhorse within the industry today is close to 380 watts. That’s an efficiency increase of almost 27 percent within that time frame. In addition, improvements in manufacturing processes and economies of scale drove the reduction of the cost to produce those modules by almost 50 percent.
Some of the key innovations in module technology that has enabled significant efficiency gains include the application of Passivated Emitter and Rear Contact (PERC) technology to solar cells, the advent of half-cut cells, increased number of printed busbars on cells and reduction of white space between cells in a module by increasing the dimension of each cell. Another technology that contributed to the efficiency leap worth nothing is bifacial modules. Power can be produced from both sides of a bifacial module, increasing the total energy generation, sometimes up to 20 percent. All these innovations helped lower the levelized cost of solar energy to point where grid parity has already been achieved in a number of states within the U.S..
Solar inverters have also undergone multiple waves of innovation throughout the years. Not only are they more efficient today, but they are safer and more sophisticated in terms of grid interaction. About half a decade ago, commercial solar systems utilized central inverters that were dimensionally larger than refrigerators and converted DC to AC at around 95 percent efficiency. Today, string inverters are typically designed into systems and are about the size of a medium suitcase and can achieve up to 99 percent efficiency. Safety improvements have also been a huge focus of the industry, driven by regulatory codes and standards like the National Electrical Code. All commercial solar inverters used today are required to have built-in DC arc-fault detection and rapid shutdown capabilities. These features not only help prevent electrical arc faults within the array but also aid first responders in the event of an emergency.
In 2017, California Rule 21 mandated that all commercial solar inverters installed within the state are required to have smart features built in to allow more effective interaction and communication with the utility grid. These new features help improve grid resiliency through support functions such as voltage regulation, frequency support and ride through capabilities. As solar penetration increases throughout the country, these features can help enhance grid stability and resiliency.
The solar industry has certainly answered the call of innovation and will continue to do so in the coming years. As Moore’s Law revolutionized the electronics industry, a similar effect is taking place within solar.