100X in 10 Years

Each February, the U.S. Department of Energy releases an analysis of total electricity generation by source withing the U.S. The February 2021 version of Electric Power Monthly (EPM) reveals that solar—at all scales—accounted for 133 terawatt-hours (TWh), or 3.3% of all the electricity generated in the nation during the year.

While 3.3% may seem like a small number when compared to the much larger portion of U.S. electricity generated by other sources such as coal (19.1%), nuclear (19.5%), or natural gas (39.9%) – the significance of this 3.3% shouldn’t get lost in the proverbial “shuffle” of other generation sources. For example, in Hawaii and California, solar is meeting more than 17% of electric demand.

Also, if you really dig through past issues of EPM, going back a decade, you will see that solar generated 1.2 TWh in 2010. In other words, U.S. electricity generation from solar has grown around 100x over the last ten years.

It most certainly took a lot of blood, sweat, and tears to get us there. Everything from new business models to endless state policy battles to manufacturing better components including solar panels, racking/tracking systems, inverters and balance of systems have provided the framework to support a dramatic scaling of solar deployment across the U.S.

And the most important thing about these numbers is not what they say about the past. It is what they suggest about the future. Solar is on a remarkable growth path. If we scale solar even 15x-20x this decade, we’ll be meeting half of U.S. electricity demand—even after accounting for growth from the electrification of transportation and heating.

For solar to meet this challenge, the industry will have to continue to evolve. One major area is storage. As solar penetrations grow on the nation’s grids, it won’t be good enough to build solar anymore—solar is going to need to be paired with storage so that it can meet evening demand, not just mid-day demand. The market is already there in several places, including the Hawaiian island of Kauai’i, where solar is meeting 34.7% of electric demand, and will meet 42.5% of demand when the next big plant comes online.

The future is ours and as long as we continue to evolve we can accomplish this. Sometimes it is useful to look back and see just how far we have come.