Next April, FORTUNE will again bring together some of the smartest people we know in sustainability for Brainstorm Green, the magazine’s annual conference on business and the environment.

This is will be our 5th Brainstorm Green–hard for me to believe, since I’ve been involved since the beginning–and we’ve again got a first-rate lineup of leaders from corporate America, the  environmental movement, the investment community and government, as well as a scattering of interesting writers, thinkers and doers about “green.”

Once again, the event will be held at the spectacular Ritz Carlton in Laguna Niguel, CA. Dates are April 16-18, 2012.

Alan Mulally

New faces for 2012 from the corporate world will include Alan Mulally, the president and CEO of Ford; Rob Walton, the chairman of Walmart; Andy Taylor, the chairman and CEO of Enteprise (they buy more cars than anyone in America); C. Larry Pope, the chairman and CEO of Smithfield Foods (they make more hot dogs than anyone in America, as I wrote in Smithfield Foods: Sustainable Pork?); Vance Bell, the chairman and CEO of Shaw Industries (the world’s largest carpet manufacturer, see my blogpost, This carpet has moral fiber); John Faraci, the chairman and CEO of International Paper; Gary Hirshberg, the CE-Yo of Stonyfield Farm; Russ Ford, the executive vice president of Shell; Bea Perez, the chief sustainability officer of Coca-Cola; and Trae Vassallo of Kleiner Perkins.

Other newcomers will include former EPA chiefs William K. Reilly and Christine Todd Whitman; he’s now with private equity firm TPG, and chaired the BP oil spill commission, she’s an energy and environmental consultant and nuclear-power advocate. We’ll talk politics and climate with  John Podesta, the chair of the Center for American Progress and former chief of staff to President Clinton. John Warner — the Ph.D. chemist, not the former U.S. Senator — will explain the promise of green chemistry.  Bonnie Nixon will deliver insight into The Sustainability Consortium. And I certainly hope that Jared Diamond, the Pulitzer Prize winning author and geographer, will counsel us on how to avoid Collapse.

Frances Beinecke

Although we meet just once a year, I like to think of Brainstorm Green as a community, albeit an ephemeral one. That’s largely because many of those who came for the first Brainstorm Green, back in 2008, have come back again and again. In particular, we are joined every year by the leaders of our programming partners–the Environmental Defense Fund, the Natural Resources Defense Council, The Nature Conservancy and Conservation International. EDF’s Fred Krupp, NRDC’s Frances Beinecke, TNC’s Mark Tercek and Glenn Prickett and CI’s Peter Seligmann will all be back in 2012.

Many other Brainstorm Green “alums” will return, too. In no particularly order: David Crane, the CEO of NRG Energy; Fisk Johnson, the chairman and CEO of S.C. Johnson; Jim Rogers, CEO of Duke Energy; Mike Brune, executive director of the Sierra Club; Scott Griffith, the chairman and CEO of Zipcar; David Neeleman, the founder and CEO of Brazil’s Azul airline; Ted Roosevelt IV of Barclay’s; Dara O’Rourke of Good Guide; and water expert Will Sarni of Deloitte.

[I'm also hoping that the incomparable Chuck Leavell -- keyboardist with the Rolling Stones, award-winning tree farmer and all-around good guy -- will return in 2012. My FORTUNE colleague Brian Dumaine, who is co-chair with me of Brainstorm Green, also functions as our musical impresario, and he tells me he's doing his best to persuade Chuck to come back.]

As always, there will be plenty to talk about–the shale gas boom, the future of renewable energy, the continuing “greening” of corporate America, the 2012 election, consumer behavior around green, corporate water strategies, electric cars, etc. The theme of the conference is, how can business help profitably solve the world’s big environmental problems?

The program remains in flux, so if you want to propose a speaker or call our attention to a new topic, please do so here at the Brainstorm Green website. You can also request a delegate invitation on the registration page. I hope to see many of you in Laguna Niguel in April.

Jeremy and Ryan Black, with acai

Sometimes, for an entrepreneur, not knowing what you are getting into is a blessing.

If brothers Jeremy and Ryan Black had known what they were up against back in 2000 when they started Sambazon, a company that makes juices, sorbet and smoothie packs from tiny purple berries that grow in the Amazon forests of Brazil, they might not have bothered.

Few Americans then had heard of acai, or knew how to pronounce it. (It’s ah-sigh-ee.) The little berries from tall skinny palm trees can be harvested only once a year, they must be frozen right away to retain freshness and then shipped to the U.S. It’s a cash business, so importers must pay farmers long before the products are sold. And who, for goodness sakes, would sell them?

Harvesting acai

Nor did Jeremy or Ryan know much about the food business. Jeremy, the older bro, who’s now 37, was a financial planner. Ryan, who’s 35, was pursuing a professional football career as a defensive back, hoping to get to the NFL, after a season in the European football league.

All they knew was one thing. “Acai is amazing,” says Jeremy. And they had an idea that if they could figure out how to turn acai into a real business, they could not only do well for themselves but do some good for farmers in the Amazon. Says Ryan: “If this berry became a household word, it could be a really strong force for sustainability in the Amazon.”

It’s taken the Sambazon guys a decade, but things are looking up these days for their company. The No. 1 producer of organic acai, Sambazon doesn’t disclose sales–they were reported at $25 million in 2008–but the company says it is profitable. It employs about 150 people, half of them based in Brazil. You can find its products not only at smoothie bars and Whole Foods, but at mainstream retailers like Safeway and Giant. And the investors in the privately-held company include savvy food guys like Steve Demos, who founded White Wave and put Silk soy milk on supermarket shelves, and Gary Hirshberg, the CE-Yo of Stonyfield Farms. They also secured investments from Root Capital, a nonprofit social investment fund that’s intended to support sustainable livelihoods in the developing world, and from the EcoEnterprises fund run by The Nature Conservancy.

It all began with a turn-of-the-millenium surfing trip to Brazil by Ryan and a friend, Ed Nichols, the third co-founder of the firm. They tried acai in frozen form with some local surfers. “We had a purple slushy bowl of goodness, and it gave you a bit of a buzz,” Ryan told me during a video chat over Skype. They returned to Brazil the following summer, visited the Amazon, and eventually raised $50,000 to buy and ship a container of frozen acai back to California. The distribution plan was simplicity itself, said Jeremy: “Let’s go find every juice bar in California and go door-to-door.” They thought about opening their own chain of acai smoothie bars.

Much of what they’ve accomplished since then has happened behind the scenes. They were the first to sponsor USDA organic certification for acai and got their supply chain certified as Fair Trade. They worked with WWF Brazil and other NGOs to make sure that the berries were harvested sustainably, and that farmers (who had been separated from markets by middlemen) were fairly paid. They built a factory in Amapa, Brazil, that today buys berries from more than 10,000 independent family growers, Ryan told me.

Because the company was always cash-short, Sambazon relied mostly on in-store giveaways and word-of-mouth marketing to expose the product to customers. They toured with musicians, and won friends in the surfing and skateboarding communities of southern California, where the company is based. Today, they have a group of “brand ambassadors” known as Team Sambazon that includes world-class surfer Rob Machado, NFL tight end Tony Gonzalez, beach volleyball star Holly McPeak, and singer Brett Dennen.

Their success has brought competition, some of it unsavory. You can find all kinds of outrageous health claims for acai on the Internet. The Sambazon website makes more modest claims:

Laboratory tests show that açaí is a rich source of antioxidants called anthocyanins, which are the same phytochemicals that provide the healthy benefits of red wine. Analysis also shows that açaí is packed with unsaturated healthy fats that have a fatty acid ratio similar to olive oil, which is considered to be a contributing factor to the low incidence of heart disease in Mediterranean populations.

…So simply put, açaí combines the best of the Mediterranean and French diets by having more antioxidants than red wine and an essential fatty acid profile similar to olive oil.

Worse, according to Ryan and Jeremy, some competitors market acai drinks that contain very little acai. Sambazon’s website says that its Sambazon Original™ Juice contains twice as much acai as its next competitor. “We knew we’d have competition, and that’s fine,” Jeremy said, but he’s concerned that the acai industry not be tainted by others’ false claims.

I first tasted acai during my visit to the Amazon last summer. It’s delicious. Since meeting Jeremy at Greenfest in Washington, D.C., I’ve become a fan of Sambazon’s smoothie packs and sorbet. I don’t know if acai (or anything else) can rightly claim to be a superfood, but I have no doubt that the Sambazon guys are trying to align their business with goal of a sustainable Amazon.

Inside the Tapajos National Forest, where 228 people have joined in a cooperative known as Coomflona, workers display sandals and wallets made of latex from rubber trees, necklaces and earrings made from the seeds of plants and tiny bottles of plant oils:

More important, they talk about how they are harvesting timber from the rainforest with extreme care, strictly limiting the number of trees that are cut, preserving younger specimens and removing the older ones with minimum impact.

These activities and others like them—harvesting acai or Brazil nuts, ecotourism, or developing oils for medicinal or cosmetic use–are absolutely vital to protecting the Amazon because they generate the income needed by the people who live there.

They’re often called sustainable livelihoods, meaning that they are ways to make a living that preserve or restore the environment.

Without them, people would resort to cattle ranching—small-scale agriculture, soy farming or illegal logging—the very activities that already have deforested nearby areas, as shown here:

Yesterday (July 21), I visited  Coomflona with a small group of reporters from the U.S., UK, France and Brazil. Before the visit, we took a charter flight from the small city of Santarem over the Tapajos forest to see the contrast between protected zones and denuded areas. Below is an image of the forest and another of deforestation, taken from the plane:

After the flight, we drove an hour from Santerem to the coop– a potential solution to the problem of deforestation, albeit at a small scale. Coomflona, which began in 2005 with lots of Brazilian government and international support, has organized people from nearby communities to exploit the rainforest in sustainable ways.

“The secret is to find the right tools to create income for the people, while preserving the forest,” says Darlyson Fernandez of the Chico Mendes Institute for Biodiversity Conservation, a government agency that supports the operation.

So far, things are going very well. Jeremias Batista Dantas, a 23-year-old local man who has emerged as a leader of the forestry, told us that the incomes of families living in the region have doubled since the coop arrived.

Before, the typical family earned about 4800 reais, or $2700 a year, mostly by subsistence farming or fishing in the Tapajos River, an Amazon tributary. Now families earn about 7500 reais ($4215) from the coop, plus ($1350) from farming or fishing on their own when timber work stops, during the rainy season.

The coop itself appears to be thriving. In 2009, according to Dantas, the operation brought in about $1.45 million dollars by harvesting 13,000 cubic meters of timber that were sold for an average of $110 per cubic meter. They brought in roughly another $100,000-exact figures were hard to come by– by selling handicrafts and oils. Operating costs were about $840,000, mostly for labor and equipment, and the profits were reinvested into the operation or spent on community development.

Most FORTUNE 500 companies would envy those margins.

Of course, the economics are not quite as simple as that. The coop’s startup costs were paid by the federal government and other nonprofits, and they were substantial. In fact, some villagers were overwhelmed when they were allocated nearly $1 million to inventory the forest, develop a timber plan, organize the community and the like.

“We were not used to dealing with that kind of money, and we had no management skills,” said Dantas, a very impressive guy who has a high school education and some technical training in forestry, but hopes to go to college soon.

What’s more timber prices could fluctuate, and there’s no guarantee that the forest will regenerate itself before too many trees are cut down. The coop’s studies rely on computer models, and reforestation rates are hard to predict. Dantas said the coop would like to be less reliant on timber by building up revenues from handicrafts and oils.

After the visit to Coomflona, we took a walk through the rainforest where I had a brief but fascinating talk with Toby Gardner, a research fellow at the University of Cambridge. With funding from The Nature Conservancy, Gardner is leading an extensive study of land use in the Amazon, to measure the social, environmental and economic impacts of such activities as forestry, soy cultivation and cattle ranching.

He told me that he very much admired the coop, but noted that it is a pilot project that can’t easily by replicated widely.

Fundamentally, he said, the people of the Amazon should aim to use land that is already deforested in ways that are intensive (i.e., as productive as possible), diverse (to generate various revenue streams and not be dependent on a single commodity) and able to capture more of the value chain (by selling processed goods or finished products rather than raw materials.) Put simply, the goal would be to extract the maximum value from deforested land and protect the rest.

For the coop, that might mean getting into the furniture business rather than selling wood. That’s a lot to ask of 228 people, who are just learning to harvest and sell timber. In theory, of course, they could cooperate with others in the city of Santerem, a big river port that’s about an hour away by road.

Santerem, as it happens, is the place from which the global agribusiness company Cargill ships soy to Europe, so that people there can feed it to cows, so that diners can enjoy meat and dairy products. (Or chicken, which set off  a controversy involving McDonald’s, Cargill and Greenpeace a few years back.) Soy farms are good for Cargill and meat-eaters but they deliver very little value to the people of the Amazon.

Better than Coomflona and other efforts like it succeed–to preserve beautiful places like this:

Disclosure: My week-long trip to Brazil, with a focus on the environment in the Amazon, is being organized by Apex-Brasil, a government-backed agency that promotes trade and investment. It’s sponsored by Electrobras, Petrobras and Banco do Brasil.

Renewable energy threatens the planet. Who knew?

Our nation runs the risk of damaging the environment, in the name of saving the environment.

There are negative consequences from producing energy from the sun, the wind and the earth.

So, at least, said Lamar Alexander, the Republican senator from Tennessee and a long-time conservationist, during a speech today at Resources for the Future.

What’s he worried about? The danger that developing thousands of wind turbines, building solar-thermal power plants which spread across the desert and cultivating acres upon acres of land for biofuels will create “energy sprawl,” consuming too much territory and threatening wildlife.

Citing a a study by the Nature Conservancy, Alexander warned that “during the next 20 years, new energy production, especially biofuels and wind power, will consume a land mass larger than the state of Nebraska.”

What’s his solution? Nuclear power, which produces lots of low-carbon electricity in a way that’s least likely to harm wildlife and the landscape.

Speaking to an audience of environmentalists at RFF, a respected, nonpartisan think tank, Alexander said, “I want to ask you to do something that gives many conservationists a stomach ache whenever it is mentioned—and that is to rethink nuclear power.”

Even though the U.S. hasn’t built a nuclear power plant since 1990 (and 12 states have laws banning them), nukes produce “70% of our carbon-free electricity,” far more than wind or solar power, he noted. Of the world’s major emitters of greenhouse gases, only the U.S. has no nuclear plants under construction. If China and India build lots of nuclear plants, at a reasonable cost—admittedly a big if—they will not only be able to compete against the U.S. with cheap labor, but with cheap low-carbon power, too.

Interesting, no? As I listened to Alexander, he struck me as a Republicans who might be willing to work  with Democrats to deal with the climate crisis. (See yesterday’s blogpost, How Republicans Can Save the Climate Bill.) After all, as he told the crowd at RFF, he grew up hiking and camping in the Great Smoky Mountains, supported strict emission standards for pollutants from coal plants and believes man-made burning of fossil fuels contributes to global warming. He opposes the mountaintop-removal method of coal mining and drives a plug-in hybrid.

Waxing lyrical, he said: “Italy may have its art, India its Taj Mahal, but we have the Great American Outdoors.”

But his love for the outdoors takes him only so far, it turns out.

When it comes to climate change politics, Alexander sticks closely to the Republican message that a cap-and-trade system to regulate carbon pollution is a tax that will raise energy prices. Even if  Democrats were to endorse to embrace the nuclear option–Alexander wants to see 100 new nuclear plants built in the next 20 years, backed by as much as $100 billion in federal loan guarantees—he won’t  support carbon regulation that would raise fuel costs, he told me after his speech.

“I’m all for climate legislation,” Alexander said, “but an economy-wide cap and trade program is a big mistake.”

So much for bipartisanship.

Even so, Alexander has called attention to a real problem–the pressures on land use created by unwise development of wind, solar and biofuels. The Nature Conservancy report, called Energy Sprawl or Energy Efficiency: Climate Policy Impacts on Natural Habitat for the United States of America, is a scientific, peer-reviewed study that compares the land-use impact of energy options. It says, among other things, that

The land-use intensity of different energy production techniques varies over three orders of magnitude, from 1.9–2.8 km²/TW hr/yr for nuclear power to 788–1000 km²/TW hr/yr for biodiesel from soy. In all scenarios, temperate deciduous forests and temperate grasslands will be most impacted by future energy development, although the magnitude of impact by wind, biomass, and coal to different habitat types is policy-specific.

Translating the findings, Alexander said:

The gold standard for land usage is nuclear power. You can get a million megawatt hours of electricity a year–that’s the standard unit the authors chose–per square mile, using nuclear power. The second most compact form of renewable energy is geothermal energy. To generate the same amount of power, coal requires four square miles, taking into account all the land required for mining and extraction. Solar thermal takes six square miles. Natural gas takes seven square miles and petroleum seventeen. Photovoltaic cells that turn sunlight directly into electricity require 14 square miles and wind is even more dilute, requiring 28 square miles.

You get the feeling Alexander really doesn’t like wind power. He says that turbines are “the length of a football field, they are noisy and their flashing lights can be seen for up to twenty miles” and that if we build enough wind turbines to generate 20 percent of the nation’s electricity (186,000) they will kill an estimated 1.4 million birds. (Maybe, but I’ve been told that cats kill more birds than wind turbines.)

By contrast, he’s confident that the nuclear waste problem is solvable and that nuclear plants are safe, citing, among others, Energy Secretary Steven Chu, a lonely pro-nuclear voice on the Obama team. Chu favors expanding federal loan guarantees for nukes.

What to make of all this? First, it’s worth noting (and Alexander did) that The Nature Conservancy did not endorse nukes in its report. In this blogpost, Rob McDonald, one of the authors, writes that his work has been “put to rhetorical use” by many, including Alexander, who assailed renewable energy “as an unprecedented assault on the American landscape” in The Wall Street Journal. That seems a little extreme no? They may not like wind turbines on Cape Cod but in much of the midwest farmers embrace them as a new cash crop.

Second, as McDonald writes:

…climate change is the big threat to America’s wildlife (and to our communities). Severe climate change has the potential to imperil many more species than energy sprawl.

So before we fret too much about energy sprawl–which can be managed by wisely siting renewable power facilities– we ought to have a strong climate regulation program in place. Alexander’s plan for a combination of nukes, electric cars and solar power on rooftops but no economy-wide carbon rules fails to meet that test.

Third, environmentalists should seriously rethink nuclear power. As Alexander put it:

My fellow Tennessean Al Gore won a Nobel Prices for arguing that global warming is the inconvenient problem. If you believe he is right, and if you are also concerned about energy sprawl, then I would suggest that nuclear power is the inconvenient solution.

Energy sprawl?

Mark Tercek left Goldman Sachs after a long and successful career midway through 2008, just before the global financial meltdown. Good timing, except that Tercek moved on to become the president and CEO of The Nature Conservancy, the world’s biggest environmental organization, as  the global climate crisis is intensifying.

He feels the pressure. There’s more work than ever to do, and money is tight at the conservancy. “This is really hard,” Tercek told me recently. “What a responsibility we have to get this right.”

Mark Tercek

By “this,” Tercek means climate change policy in general and REDD in particular. REDD stands for Reducing Emissions from Degradation and Deforestation, and it’s an absolutely crucial strategy for dealing with climate change that requires slowing the growth of agriculture, forestry and cattle ranching to protect forests in places like Indonesia and Brazil. Because tropical forests are being degraded or cut down at an alarming rate, Indonesia and Brazil are ranked No. 3 and No. 4, respectively, by some studies when it comes to carbon emissions, behind the U.S. and China  but ahead of Japan or Germany. Deforestation could account for as much as 25 percent of emissions, these studies show.

The fundamental idea behind REDD is to get businesses and governments in richer countries to help finance sustainable livelihoods for people in poor countries so they don’t have to cut down trees to earn a living. While it takes some doing to get your head around the idea that Americans and Europeans will pay poor people not to cut down trees, some countries like Norway are already big backers of REDD and companies like Dell and Marriott  are working with enviros like Conservation International to preserve forests in Madagascar and Brazil. The Nature Conservancy has for more than a decade been leading a project to protect 1.5 million acres of tropical forest that were threatened in Bolivia. The conservancy says the project “is expected to prevent the release of up to 5.8 million tons of carbon dioxide over the next 30 years,” while preserving biodiversity and protecting communities.

“There’s no higher priority for me at The Nature Conservancy than REDD,” Tercek says. “We’re extremely confident it can work, which is not say that it’s easy.” In fact, there are tricky technical, political and governance isues around  REDD, as this post on the conservancy’s blog, Cool Green Science, explains. How, for instance, after paying people not to cut down trees do the financial types make sure they get the sequestered carbon they have paid for? The answer is, essentially, satellite photography, but trust me, there are other, more complicated issues.

Give his experience as a deal-maker, Tercek would seem to be the right man to help figure all this out. Mark, who is 52, grew up in a working class neighborhood of Cleveland. His first exposure to business—as a paperboy for the Cleveland Plain Dealer—gave him an opportunity to win a scholarship to the Western Reserve Academy, an elite prep school. (He is a loyal alum who has been president of its board.) From there, he went on to Williams College, did a stint in Japan with Bank of America, picked up an MBA at Harvard Business School and found a home at Goldman, beginning in 1984. “I liked investment banking, every minute of it,” he says.

In 2006, Tercek was put in charge of the Goldman’s new Center for Environmental Markets by Hank Paulson, who was then Goldman’s CEO and the board chairman of The Nature Conservancy. Paulson wanted the bank to turn environmental issues into a business opportunities, which is why he put a commercial banker like Tercek in charge. For his part, Tercek got a crash course in climate change, which only intensified his interest in the environment. That had taken root when he and his wife, Amy, took their four children on nature trips to places like Costa Rica, Belize and Tanzania.

“If you see the wonders of nature through the eyes of children, you’d have to be a real dolt not to step back and think about, ‘what kind of world are we going to leave them?’ “ Tercek says.

The Nature Conservancy job puts him in a position to have a big impact. The conservancy is by far the world’s biggest conservation group, with an operating budget of nearly $500 million, about 3,600 employes including hundreds of scientists, and chapters in all 50 states and 36 countries. Unfortunately, the group, like other NGOs, has suffered during the current recession, and so Tercek has overseen the layoffs of about 10 percent of the staff. He’s also got to balance the needs of the state chapters, which raise most of the money, and the global operations, where the needs for conservation are greatest.

The financial crisis, Tercek says, has been “a huge reminder that we don’t have unlimited resources. We have to be really disciplined about identifying our highest priorities, and making sure they are fully funded not only with money but with talent.”

Tercek is looking to build alliances with other NGOs—the Nature Conservancy has joined the U.S. Climate Action Partnership, for example—as well as with business. Corporate backing for both the voluntary and regulated carbon markets, for example, will be essential to save forests.

“I believe we can harness the power of business to solve big issues,” Tercek says.

Mark spoke at FORTUNE’s Brainstorm Green conference about business and the environment while at Goldman in 2008, and I’m pleased to say that he will be back again in 2010, this time representing The Nature Conservancy.

Measuring trees in Bolivia as part of a sustainable forestry program

photo credits: The Nature Conservancy

Not long ago, Big Business and environmental activists were sworn enemies. No more. Today, companies and NGOs come together to work creatively around a variety of issues—from climate change to recycling to protecting the Amazon, from cleaning up dirty businesses like gold mining and to “greening” professional sports. One place they literally come together is at Brainstorm Green, FORTUNE’s conference about business and the environment, which will be back on Earth Day, 2009.

Helping to create Brainstorm Green was a highlight of my 12 years at FORTUNE, and I’m pleased that I’ll be back this year, co-chairing the event with my colleague Brian Dumaine, FORTUNE’s global editor. The program for this year’s Brainstorm Green is still a work in progress, but a group of us got a draft agenda down on paper last week and I’m confident that it will again be a lively, exciting, information-packed event. The theme, once again, will be: How can business help solve the world’s biggest environmental problems?

We’ll discuss and debate climate change regulation, “clean coal,” nuclear power, electric cars, the smart grid, investing in green, renewable energy, sustainable consumption (if there is such a thing), carbon finance and too many other topics to list here.

What makes Brainstorm Green special is the diversity of the crowd. This year, we’ll again hear from many of America’s most important environmental leaders, including Fred Krupp of Environmental Defense, Glenn Prickett of Conservation International, Mark Tercek of The Nature Conservancy (who was there last year on behalf of Goldman Sachs), David Hawkins of the Natural Resources Defense Council, Mindy Lubber of Ceres and Mike Brune of Rainforest Action Network. At least two dozen CEOs of big and medium-sized companies have agreed to speak, including Shai Agassi of Better Place (the electric car company), Ray Anderson of Interface, Carl Bass of Autodesk, David Crane of NRG Energy, Jeff Hollender of Seventh Generation, Fisk Johnson of S.C. Johnson, Donald Knauss of Clorox, Mike Morris of American Electric Power, Ralph Peterson of CH2M Hill, Jim Rogers of Duke Energy and Tom Werner of SunPower.

Other companies sending speakers include Wal-Mart, McDonald’s, Coca-Cola, Goldman Sachs, Mars, Intel, Boeing, McKinsey, the private-equity firm KKR and architectural firm HOK. That list is sure to grow.

We’ll also be joined by speakers whose ideas are shaping the sustainability debate. I’m looking forward to spending time with Paul Hawken, whose books have shaped much of my own thinking about business and the environment. The dynamic Van Jones, who is profiled in the current issue of The New York by Betsy Kolbert,  will talk about green jobs. The always-inspiring Janine Benyus, who spoke last year, will be back to show us how biomimicry works in practice. My friend Joel Makower, the guru of green business and author of Strategies for the Green Economy, will return as well.

Venture capitalists from some of America’s top firms and entrepreneurs touting exciting startups will round out the group. We’re hoping to attract senior officials from the new Obama administration as well.

You can find a full list of speakers on the Brainstorm Green website. That’s also the best place to propose new speakers or to sign up for the event. (FORTUNE screens all participants.) We’ll meet in a beautiful setting—the Ritz Carlton Hotel in Laguna Niguel, CA, and I’m looking forward to seeing many of you blogreaders there.

Public interest groups need more scrutiny. So a forthcoming book called Green Inc: An Environmental Insider Reveals How a Good Cause Has Gone Bad (Lyons Press) by a journalist and activist named Christine MacDonald piqued my interest. MacDonald argues that big green environmental groups – specifically Conservation International (where she worked briefly), The Nature Conservancy and the World Wildlife Fund — have become too cozy with corporate America.

The big conservation groups are “deforming themselves,” engaging in “questionable practices” and cultivating “unsavory corporate ties,” she writes. They are conflicted because they take corporate money. They are too quick to provide cover for bad actors:

Groups that once dedicated themselves solely to saving pandas and parklands today compete for the favors of mining operations that remove entire mountaintops, logging and paper companies that clear-cut old growth forests, and homebuilders who contribute to urban sprawl. They rely on funds from cruise ship companies, despite the industry’s record for polluting the oceans. Among the most generous donors are the biggest environmental scofflaws of all: energy companies.

It’s an explosive charge—but MacDonald fails to prove it. The book is spotty, uneven and ultimately disappointing, for the most part lacking the specifics that would show how conservation groups either enabled or covered up bad corporate behavior. But Green Inc. does raise provocative questions about the business models of some of America’s most important green groups.

MacDonald’s basic point—that conservation groups work closely with polluters—is both true and unremarkable. No one would expect the pastor of a church to close its doors to sinners; why, then, should we ask environmental groups to refuse to work with oil companies, mining companies, home builders or giant retailers like Wal-Mart. (McDonald, as it happens, also uses religious language to make her case, writing at one point that CI and others are “guilty of making deals with the devils of deforestation, habitat destruction, and global warming.”) Hey, people rob banks because that’s where the money is. Environmentalists need to get their hands dirty and deal with polluters.

It’s important to understand the role that CI, TNC and WWF play in the NGO ecosystem. They are collaborators, not activist groups. Other green NGOs are activists, and many are both essential and effective—the Rainforest Action Network, Greenpeace, Forest Ethics and Earthworks, to name just a few. But after they raise a ruckus, big companies frequently turn to groups like CI, TNC and WWF for guidance and help in making those pesky activists go away. (You can almost think of the Rainforest Action Network as the business development arm of CI.) Other NGOs like the Environmental Defense Fund and the Natural Resources Defense Council juggle both roles—they are sometime allies, sometime critics of corporate behavior. They’ll sue a company one day, then make nice the next. Hey, the world’s a complicated place.

The key question is, what impact do the collaborative groups have after they engage? I’ve spent a lot of time looking at work done by Conservation International (with Wal-Mart, Starbucks, McDonald’s and Marriott), less with World Wildlife Fund (mostly with Coca-Cola) and none with The Nature Conservancy. My strong belief—informed by reporting—is that they do a lot more good than harm. CI helped guide Wal-Mart through its ambitious and impressive sustainability drive. (By coincidence, I was on a reporting trip today with people from both Wal-Mart and CI who are working together to clean up a big, polluting industry. More to come…) WWF is doing superb work around water and supply chain with Coke, and Jason Clay, who works there (and who I wrote a column about last month), is an important thinker around the question of how to make agriculture more sustainable

Having said that—MacDonald tells a couple of stories that I’d like to know more about. She writes about CI’s work with Bunge in Brazil, saying that CI has allied itself with the company and against local groups protesting deforestation for soy. She accuses an alliance of companies, NGOs and governments called the Business and Biodiversity Offset Program of helping a mining consortium develop valuable forests in Madagascar. LI’d like to know more—so anyone who has insight into these projects, please email me.

I’ve also come away from this book wondering whether CI, WWF and TNC pull their punches because they don’t want to offend corporate donors. I think these groups and others need to be more transparent about their funding sources, particularly since they ask the public for money. They say they don’t depend on corporate donations or fees. (CI’s Glenn Prickett tells me that less than 10% of their funds come from corporate contributions.) But that accounting does not include donations from corporate executives acting as individuals or family foundations. MacDonald writes that CI got $21 million from the Walton Family Foundation (founding family of Wal-Mart) in 2005, representing nearly a quarter of its revenues that year. I wonder about CI’s partnership with Fiji Water, especially since one of the company’s owner sits on the CI board. (Shouldn’t a conservation group discourage consumption of bottled water?) MacDonald also writes that TNC received “hundreds of thousands of dollars in Shell donations” before giving the company a leadership award. If true, that’s yucky.

Here’s a thought: Whenever an NGO produces a press release praising a company, or announcing a partnership, or giving an award, maybe it should disclose how much money it has been paid by the company for consulting and how much money executives, company founders and their foundations have donated.

You might argue that it would be simpler for these groups to refuse all corporate money. I disagree. They provide valuable advice and expertise to companies; there’s no reason that individual or foundation donors should foot the bill when CI helps Starbucks develop a program for rewarding coffee growers who embrace sustainable practices or WWF helps the sugar industry develop more sustainable growing practices.

But more transparency would help. To that end, I will ask CI how much money it has taken in from Fiji Water and WWF how much it has gotten from Coke. (In the interests of transparency, you should know that CI is a programming partner of Fortune’s Brainstorm: Green, a conference on business and the environment that I chair; my wife works for Greenpeace; occasionally I am paid for giving speeches and moderating panels but if the client is a public company, I give the money away; and my daughter’s a summer intern at Edelman, a PR firm with a big sustainability practice. I try to set all that aside when I write.)

Your thoughts?