Solar panels at a photovoltaic power station in Songxi county in southeastern China’s Fujian province. Aug. 21, 2016. (Chinatopix/AP)

Bill Joy, cofounder of Sun Microsystems, is a computer scientist, inventor and investor. He is a principal and chief scientist at Water Street Capital.

We are living unsustainably. Greenhouse gas emissions threaten runaway climate change, and excessive nitrogen pollutes our waters. We sense the impending sixth extinction but are shocked by breaking news of a mass decline in insects. Information technology has rapidly transformed our economy but not areas such as energy, materials and food, where we desperately need sustainability. We need to change our course.

Using a target list of 25 clean-tech “grand challenges,” I worked for over a decade to find, fund and commercialize big breakthroughs. One such challenge was radically cheaper batteries. Another was sustainable building materials, especially concrete. A third target was sustainable “meat.” They’re not the only breakthroughs that will help us transition to a more sustainable economy and society, but innovations in these three fields have the potential to radically transform the way we live. In the interest of full disclosure, I’m an investor in some of these companies; I want to tell you about them because I’m convinced they can change the world.