Oct 18, 2013 · 1 minute

This week, we put out a graphic explainer on the future of clean tech, in partnership with Explainer Music. The piece notes that while CO2 emissions are expected to rise over the coming decades, investment from venture firms in clean tech solutions is way down.

What happened? It wasn't so long ago that Kleiner Perkins investor John Doerr gave an impassioned TED talk, demanding we get serious about clean tech investment or else "we're not going to make it." And if VCs are willing to drop millions on photo-sharing apps, why can't they throw a little toward, you know, saving the world?

Unfortunately, it's a lot more complicated than that. As Netscape founder and investor Marc Andreessen noted at our last PandoMonthly, it can take hundreds of millions of dollars to make a difference in many clean tech sectors. And even then it can take ten years or more before those changes take effect. For a venture capitalist, it may not be the smartest play. Even Doerr admits, “I encouraged us to do too much green too fast.”

(Disclosure: Marc Andreessen is an investor in PandoDaily)

But that thinking hasn't dampened Elon Musk's ambitions. The Tesla/SpaceX/SolarCity enterpreneur says, "You only build value in a company if you're doing hard work to solve tough problems. That's why companies are valuable."

Despite the challenges, all three of them believe there's a way forward, we just haven't figured out the funding model yet. Or as Andreessen puts it, "Somewhere between the next photo-sharing app and Solyndra -- somewhere in there, there's a sweet spot."

Watch the three tech luminaries talk about the future of clean tech in our newest PandoMonthly mashup.

[An Explainer Music video. Edited by David Holmes and Sharon Shattuck. Music by Andrew Bean]

Other PandoMonthly mashups:

"The Netscape Story"

"Top investors explain bitcoin"

“How irresponsible debt launched three careers”

“Peter Thiel, Brian Chesky, and others weigh in on what’s wrong with education”

“The most profane PandoMonthly moments: An R-rated supercut”