KXLY April 22, 2021 2:30 AM newsfeedback@fool.com (Dave Kovaleski) Posted: Updated: April 22, 2021 3:27 AM Earth Day was established in 1970 to raise awareness about the state of our environment and is seen as the birth of the modern environmental movement. That movement has taken root in the world of investing. Environmental, social, and governance, or ESG, investing, has become increasingly popular as more people want to support companies that are helping to protect the environment. A great way to not only identify these companies, but also to invest in them, is through exchange-traded funds (ETFs) that exclusively focus on ESG. In honor of Earth Day 2021, which falls on April 21, here are three ETFs that seek to do good by the environment and investors. All three of these ETFs focus on clean energy companies.