One of the world’s biggest challenges is finding ways to reverse climate change. No one can escape the impact from the growing accumulation of greenhouse gases in the atmosphere and the resulting rising temperatures. This year’s unprecedented string of Atlantic hurricanes is just a harbinger of things to come.

Climate change won’t be reversed by reducing the number of people living on the planet or by cutting economic growth or standards of living. The only way climate change will be solved is by continuing to develop new technologies and turning them into products and services that either reduce greenhouse gas emissions or capture and sequester emissions that have already been emitted.

There is a model for doing this sort of thing; it’s called Silicon Valley. The valley (and other places like it around the world) generally does a masterful job of taking new ideas and technologies and turning them into global companies. Think Intel and microprocessors, Genentech and recombinant DNA, Netscape and the Web, or Tesla and electric cars.

Unfortunately, there are aspects of the Silicon Valley model that are not well suited to tackling climate change. Because of that, argue the authors of this issue’s cover story “The Investment Gap That Threatens the Planet,” vital emerging technologies that might reverse climate change are not being funded.

“The amount of capital flowing to earlystage solutions is disturbingly low, despite the critical role that these investments play in mitigating climate change,” write Scott Burger, Fiona Murray, Sarah Kearney, and Liqian Ma.

The main problem in this instance with the Silicon Valley model is that the overriding goal—often the only goal—of venture capitalists (VCs) is to maximize profits. There are a small but growing number of VCs that also consider social impact when making investment decisions, but even they seek to generate financial returns that are comparable to those of traditional VCs.

There is a myth that VCs are a daring lot, willing to bet millions and even billions of dollars on risky and unproven schemes. In fact, most VCs are risk-averse. Some invest in ideas that are already proven—witness the staggering number of me-too startups in Silicon Valley. Others invest in companies that off er only incremental change. And then there are the VCs who invest in software or Web-based startups where the cost of developing the product is minimal.

In this kind of environment it is very diffi cult to find VCs who are willing to bet on a risky, early-stage, science-based startup that may take years to develop a commercially viable product. What makes these ventures even less likely to get funding is that they are usually developing physical products (such as waste-heat recovery technologies) and hence require much more capital than a typical Silicon Valley startup.

And that, argue the authors, is where philanthropy comes in. Because philanthropists are not solely driven by financial returns, they are uniquely suited to invest in emerging green technologies.

These philanthropic investments can come in many forms. It might be a grant, a no-interest or low-interest loan, a programrelated investment, or an investment from the endowment. In all of these cases, philanthropists can put social return above or on par with financial return. Philanthropists have been reluctant to use all of their capital this way in the past. I hope this time it will be different.