No, it's not an alcohol infusion, though there's some decent vintage flowing. The hope comes from the conversations I've been having with a collection of venture capitalists, entrepreneurs, and corporate innovation leaders, at an annual gathering convened by VantagePoint Venture Partners, the cleantech venture fund to which I am an advisor. Each year, this event reinvigorates and reminds me why I love what I do for a living: The copious innovation and ingenuity taking place in the emerging green economy by companies both large and small.

This is no conclave of companies that are "going green" or "greening up." The businesspeople present here in Napa are at the center of a revolution that even some of them aren't yet able to clearly see: a mashup of energy technology, information technology, building technology, vehicle technology, material technology, and water technology -- and the products, services and businesses that stand to transform our lives over the next decade or two, just as much as, say, the Internet has.

This is hardly the only cleantech conference I attend during the course of a year, but it's the only one that includes a frank and open discussion among a small group of big companies about their perspectives and strategies on cleantech and the green economy, and how they're addressing them. The participants aren't corporate marketing executives or even chief sustainability officers. Rather, the representatives of the global companies present have titles like Vice President, Strategic Planning and Development, Senior Vice President of Emerging Business and Chief Innovation Catalyst. They are joined here by the founders of two dozen or so entrepreneurial cleantech companies.

As much as I like hearing from the entrepreneurs -- each one's presentation offers a cram course in a technology or trend, as well as some innovative approach to addressing it -- it's the big corporations that I find most interesting. The VantagePoint event is a rare opportunity to get past the marketing pitches and well-scrubbed executive talking points to hear the real skinny: how some of the world's largest companies are thinking about sustainability and harnessing it as an foundation of innovation.

It's nearly impossible to relate the full measure of the discussions, but I thought I'd share some tidbits about several companies, including a chemical company, a consumer products company and a major retailer. The rules of engagement for this event are what's known as the Chatham House Rule -- in essence, that the information discussed can be shared, but not the individuals' names or affiliations. The Chatham House Rule typically governs meetings where people want to share information openly and speak freely, but not beyond the immediate group.

First, the chemical company. For several years, it has been engaged in an aggressive effort to do with biology what chemistry can't do, creating products that are created at lower temperatures and with far fewer toxic inputs. The company says it is pursuing what it dubs "unique, disruptive science with significant market opportunity." In the lab are a range of biofuels, biomaterials, bioadhesives and more. For example, there's a carpeting fiber made from corn instead of petro-based nylon that requires nearly a third less energy and emits nearly two-thirds fewer greenhouse gases. It is being manufactured at a repurposed polyester factory. The demand is there from both consumers and corporate buyers, the company says, though pricing is a challenge: With oil prices down, the cost of nylon has dropped by nearly two-thirds over the past year, making the bioproduct less competitive than the petro-based one. Still, the company is optimistic over the long term. "We see many places where biology can win over chemistry."

Next up, the consumer products company. It has created a set of sustainability design principles for all of its thousands of products -- "supported by sound and transparent assumptions, good science, and substantiated by data" -- and has amped up its commitment to make these products with significant environmental improvements and no price premium to customers. And at the same time, it aims to reduce its overall emissions of carbon dioxide and waste, and use of energy and water, by 20 percent within five years.

Along the way, the company is asking the tough questions: Given that almost all of its packaging is petroleum-based, "How do we make packaging from alternative, renewable material" -- and do so without adding costs? There are promising experiments -- in one case, working with a Brazilian company to make plastics from sugar.

Many of these innovations are coming from new kinds of partnerships, in which it is working with others to find breakthrough green innovations. That's a new approach for the company, and one it views as its path forward. "Companies that don't adopt an open innovation approach won't be competitive in 10 to 20 years," says the executive. "You have to look outside your walls."

Finally, the retailer. It's probably not the one you think -- this one hasn't been particularly visible in the green world -- but its ambitions are significant: It wants to become the hub for your home energy needs. For this retailer, that involves selling a vast range of emerging products: electric bikes and scooters, maybe even electric cars; home energy optimization products, including both hardware and software that monitor your energy use and help you control it; solar panels and other renewable energy products; and more.

And maybe even services: shared-use vehicles, solar installation services, home energy audits and the like. This retailer views a multi-billion-dollar opportunity in becoming the go-to place for homeowners and small businesses to save energy and costs and to buy and install cutting-edge green technologies into their homes and offices.

What these three companies have in common, other than their vast global reach, is a strong vision of where the world is going and what's needed to succeed in the coming years. They understand that markets are shifting, as technology inexorably marches forward. Combined with growing environmental and energy concerns and emerging markets around the world, it creates an unparalleled opportunity to manufacture and sell products with more benign inputs and outcomes. And they're doing this amid one of the worst economies ever, pushing forward with the understanding that tough times often create the best opportunities to advance breakthrough change.

Their efforts are buttressed by innovations coming from hundreds of start-ups that are creating the next-gen building blocks of the green economy -- ambitious entrepreneurs, many with awesome track records of creating transformative technologies and companies. Some of them are here, sharing their innovations with their larger corporate brethren, both parties looking for the Next Big (Green) Thing.

There's a palpable sense of excitement here in Napa, as companies large and small sip cautiously the fine wine of emerging opportunity and inhale the delicate aroma of hope. For the moment, at least, it's intoxicating.