Small companies have the nimbleness to achieve radical innovations, but they lack scale. On the other end of the spectrum are large companies that have the scale, but face the uncertainty of taking something that is working and trying to do it in a new way.

These represent challenges impeding the development of the kinds of radical breakthroughs needed to address some of the world's biggest challenges, such as climate change and ecosystem degradation.

"What science is telling us at the moment is to make sustainability real, we need big, transformational changes in the way the industrial world economy works," said Marc Gunther, GreenBiz.com senior writer.

Gunther explored on Wednesday how some of the world's largest companies are taking steps to find and nurture small and sometimes little-known start-ups working on radically innovative technologies but lack the funding and the scale needed to move the needle forward.

Business leaders at the GreenBiz Innovation Forum also heard firsthand from a small company that has made radical innovation part of its business model -- by necessity.

"For Method, we're probably the smallest consumer products company out there, with few exceptions," said Adam Lowry, Method co-founder. "So for us, in order to compete in the category, we have to radically innovate because we don't have the scale."

He pointed to Method's concentrated laundry detergent that is eight times more concentrated than conventional versions, uses 75 percent less packaging, and boasts a 35 percent smaller carbon footprint. It is the second iteration of Method's 3x laundry detergent, which the company discontinued even though it represented a significant portion of its business.

"As a smaller company, we have to do that. We don't have a choice," Lowry said. "And b), it's easy for us to do. Let's face it: We don't have Wall Street breathing down our necks."

Method is a $100 million business with nine people working full time on research and development. In comparison, Procter and Gamble has 9,000 working in global R&D. Unilever has 15 global brands, each with revenue greater than $1 billion.