Bill Gates is currently worth more than $90 billion — but no one can say that he isn't trying to give back. The Microsoft co-founder has vowed to give away more than half of his fortune and his charitable organization, The Bill and Melinda Gates Foundation, has given away $41.3 billion to various international and domestic causes to date
Here are three ways Bill Gates is spending billions:
Over the next five years, the Bill and Melinda Gates Foundation plans to invest $1.7 billion in U.S. public education. The tech billionaire shared how he and his wife plan to spend this money at the Council of the Great City Schools in October.
Sixty percent of the $1.7 billion investment will fund curriculum improvements and help identify local problems and solutions, 25 percent will focus on what Gates describes as "big bets," and the remaining 15 percent will be spent on advancements in charter education.
According to Gates, one of the biggest issues in public education is inequality.
"Melinda and I made public education our top priority in the U.S. because we wanted to do something about the disparity in achievement and post-secondary success for students of color and low-income students," he says. "That inequity persists today, and we are just as determined now to eliminate it as we were when we started."
Roughly a year ago, Gates launched clean-energy investment fun, Breakthrough Energy Ventures, with the help of other famous billionaires like Jeff Bezos, Richard Branson and Jack Ma. Gates serves as the co-chair of the board with LinkedIn co-founder Reid Hoffman.
Under his leadership, Gates is using the $1 billion fund to invest in promising but underfunded technologies that could help humans "adapt to the climate change that is already affecting the planet, and develop new tools that will keep the problem from getting worse."
These particularly promising areas include grid-scale storage, liquid fuels, mini-grids, alternative building materials and geothermal power. Gates believe that investing in these fields could have real results.
"Breakthroughs in storage — for example, storing energy as heat or in flywheels — would make today's renewable technology more practical and affordable," he explains.
The Bill and Melinda Gates Foundation spends millions promoting global health initiatives around the world. In 2016, the foundation raised nearly $13 billion to eradicate AIDS, tuberculosis and malaria.
Foege has served as a mentor to the Gates since 1999 and has helped inform their global health philanthropy. Beyond answering questions and giving academic advice, Foege gave Gates a list of 81 books and reports on global health issues.
"All these books opened a new world for me," writes Gates. "Making Bill's passion for fighting poverty and disease a passion of my own."
Like this story? Like CNBC Make It on Facebook!