Coal is dirty. But coal is driving the U.S., Chinese and Indian economies. And therefore, coal is not going away. Renewable energy sources like solar and wind generate only 1 percent of the world's electricity. Do the math: Making coal burn cleaner might be the most pressing environmental problem that no one talks about.

Despite recent estimates that pollution from China's booming coal industry reaches U.S. shores in as little as five days, the green-tech investment boom that has funded the rise of biofuels has bypassed coal. Even the head of the World Coal Institute recently proclaimed the last 10 years "a lost decade" for clean coal, saying it's time to play catch-up.

Stanford's Jeremy Carl, a research fellow in the Program on Energy and Sustainable Development, couldn't agree more. He spoke on the phone with Wired News to discuss China, the holy grail of clean coal and how many coal plants he'd trade for Kyoto's accomplishments.

Stanford research fellow Jeremy Carl says, "Coal is as dirty as it gets," but warns against throwing the possibly cleaned-up baby out with the dirty bathwater.

Wired News: Why'd you get into clean coal?

Jeremy Carl: I looked at the numbers. It's a question of where the big sources of emissions are and where we can attack them.

WN: Can you give us an idea of the scale of coal power? Can you put coal in context as an energy source?

Carl: Only oil makes a bigger contribution to global energy. In terms of energy in the industrial world, it's about 40 percent of electricity production.

WN: How dirty is coal?

Carl: Coal is as dirty as it gets. Coal has every element in the periodic table. And depending where in the world you get it from, "coal" can mean 100 different substances. If you sent the sort of coal you might use in a typical Indian plant to a supermodern boiler in Japan, it would shut the place down.

WN: But there's got to be good things about coal.

Carl: It's cheap. And coal doesn't have the kind of extreme risk that nuclear power has. You're not going to build a dirty bomb out of coal. And unlike other fossil fuels, it is really widely distributed, so there is less of a coal OPEC.

WN: And that distribution would seem to make resource wars less likely to break out over coal?

Carl: Yes.

WN: Is there an energy source that could replace coal?

Carl: Natural gas is the only viable replacement, and it's not clear that the natural-gas supply could scale up to replace coal.

WN: So, how can we can make coal cleaner?

Carl: The most-well-known is flue-gas desulfurization, which takes sulfur dioxide out of smoke stacks, and came out of concerns about acid rain. There are other pollution-control devices for nitrogen oxide and mercury filters.

WN: What about up-and-coming technologies like carbon capture and sequestration? Can you tell us about that?

Carl: You're taking carbon from a smokestack and pressure-injecting it into a geological formation of some sort. We actually already do this process at an industrial level. We know how this works.

WN: Seems like we're spending a lot of time on the backend scrubbing pollutants out. Should we be designing in a cleaner process on the front end?

Carl: A lot of people point to integrated gasification-combined-cycle (IGCC) plants, which gasify coal before burning it, as the holy grail because they get you a cleaner process. It gives you a more concentrated stream of carbon that you can sequester underground more cheaply. The capital cost is very high, though, and we don't have a lot of experience in designing them.

WN: We hear a lot about China's coal industry. Can you compare it with the U.S. industry, which ranks second in the world?

Carl: We mine about (1.1 billion tons) of coal per year. China was at about 1.4 billion tons seven years ago. Now they are at 2.4 billion tons. So, they essentially took the second-biggest coal industry in the whole world and replicated it in seven years. And if you look at the Chinese plans, they plan to ramp it up even more in the future.

WN: Given the obvious environmental impacts of these plants, why don't we have better answers for these problems than the Kyoto Protocol (which the United States didn't sign, and which exempted China and India from emissions restrictions)?

Carl: I'll give you a speculative, personal answer. It has to do with the politics of the type of people who were negotiating Kyoto. And the pressure put on by environmental groups that were uncomfortable with coal. There was just so much pressure on the symbolic importance of getting a deal done.

WN: What would you have rather seen?

Carl: I think there has been some really good criticism that says, "Was the U.N. really a good forum for this? Or would it have been better to have taken the 10 countries who consume 60 percent of global energy and do something with real teeth in it?" I think that would have been a much better approach.

I would have happily traded every emissions gain from Kyoto for eight clean coal plants sequestering carbon in different countries. Because then we could have a real discussion that says, "This works. Now let's see who has to bear the cost."

WN: Why would that be such a big deal?

Carl: Because right now we're having a conversation with China and India where we're trying to get China and India to build clean coal plants by saying, "Here's this thing that's never been tried before at a mass scale. You should build one." And that's not going to work.

The opportunity to engage Kim Jong-il, the leader of the Democratic Peoples Republic of Korea (DPRK), in serious dialogue is inherently attractive. A face-to-face meeting with Kim has the potential to break through a fog of misperception and mistrust.

Given the nature of the DPRK system, the key decisions can only be made at the very top of the pyramid of power. One summit encounter is therefore potentially more valuable then scores of ministerial meetings or talks among senior officials.

These opportunities have unfortunately been extremely rare. Despite some 35 years of intermittent dialogue going back to the South-North talks held in 1972, this would mark only the second time the top leaders of divided Korea have met each other.

The hope for momentum created by the historic meeting of President Kim Dae-jung with Kim Jong-il in Pyongyang in June 2000 swiftly dissipated, disappointing many Koreans.

This may appear to be the right moment to restore the impetus to the North-South summitry. Since the 2000 summit, the process of engagement between the Koreas has deepened dramatically, ranging from extended contacts among officials to the flow of tourists, at least from the South to the North, across the border.

Economic exchanges are widespread, from the Gaeseong industrial park to a growing trade in goods. And the six-party talks to reach an agreement to dismantle the DPRK's nuclear program are at least moving forward, in large part due to the resumption of direct diplomatic negotiations between Pyongyang and Washington.

There are serious reasons, however, to question whether this is the right time for a second inter-Korean summit.

First and foremost, President Roh Moo-hyun is, in every sense of the word, a lame duck. When the summit was scheduled to take place, it was less than three months until the presidential election.

The election campaign is unusually uncertain, with the ruling party and its allies still in the process of selecting their nominee. Polls indicate that a change in leadership --bringing the opposition Grand National Party to power -- is very possible.

While he remains in office, President Roh has every right to exercise his authority and leadership. But given the political uncertainties, and the vital nature of inter-Korean relations, it would seem imperative to secure bipartisan support not only for the summit but also for the policy outcome.

For any gains to be meaningful, there should be some assurance that these policies will continue in place whomever succeeds as president.

Without that broad support, charges that the summit meeting is motivated more by domestic political considerations gain credence.

Even worse, Pyongyang's decision to agree to hold the summit may also be a crude attempt on its part to try to influence the ROK election in favor of the progressive camp. Even if these charges are not true, they undermine the value that this summit may have to shape a long-term future for the peninsula.

The timing of the summit is also problematic because the nuclear negotiations with the DPRK have reached a very delicate moment.

The temporary halt to the operation of the nuclear reactor at Yongbyon and the reintroduction of international inspectors was an important gesture.

But the DPRK has not yet clearly decided to irreversibly disable its nuclear facilities and fully disclose its nuclear programs and arsenals.

The Roh administration claims this summit will reinforce this negotiation. But it also has declared that the nuclear issue will not be on the summit agenda. In the absence of a dismantlement deal, this summit may only serve to recognize the DPRK's claim to the status of a nuclear power.

But all of these problems of timing take a back seat, in my view, to the location of the inter-Korean summit. Kim Jong-il committed himself, in the 2000 joint declaration, to a return visit to Seoul. This was not a trivial matter -- it was perhaps the most difficult issue in the talks, as Kim Dae-jung said upon return to Seoul.

Everyone understands the historic significance of a visit by Kim to Seoul. It would finally signal the DPRK's acceptance of the legitimacy of the ROK and its leadership and the abandonment of its historic aim to force unification under its banner.

The DPRK leadership would be compelled to show its own people images of their leader in the glittering streets of Seoul. That visit alone could go much farther than any peace declaration, any agreement on boundaries, any military confidence-building measures, or any economic investment deals, toward bringing a permanent peace to the Korean Peninsula.

If this summit had occurred in the right place, then the issues of timing would be incidental. No one could object to a breakthrough of that magnitude. Unfortunately, Kim Jong-il was not pressed to live up to his commitment. If this meeting achieves anything, it should make it clear that the next summit will only be held in Seoul.

Physicist Wolfgang "Pief" K. H. Panofsky, who co-created a historic undergraduate course at Stanford that gave rise to CISAC, remained an important contributor to the center's research until his death on Sept. 24.

In 1970 Panofsky, then director of the Stanford Linear Accelerator Center, joined John Barton, a Stanford Law School professor, and John Lewis, a political science professor, in creating the undergraduate course, Arms Control and Disarmament, to which CISAC traces its origin. The course, which continues today as International Security in a Changing World, taught students about how international security policy is made and illuminated the dangers of a possible nuclear war.

"We have lost a close and revered colleague in Pief Panofksy," said CISAC co-director Scott Sagan. "Without Pief, John Barton, and John Lewis, the center would not have been created when it was, through the course on arms control and international security. And his continued involvement with CISAC over the years enriched our research immeasurably."

A few days before he passed away, Panofsky attended a Stanford workshop, held at CISAC Sept. 19-21, to examine the security implications of increased global reliance on nuclear power. Dean Wilkening, CISAC senior research scientist, said that as the workshop concluded, Panofsky left the group of 40 experts with the reminder that events in the next few decades could have a dramatic impact on the expansion of nuclear power.

He referred to events such as "regime change in states with uranium enrichment or plutonium reprocessing facilities, the discovery of inventory discrepancies within the nuclear fuel cycle where significant quantities of fissile material are unaccounted for, and intercepts of illicit trafficking of a significant quantity of fissile material," Wilkening said, a list Michael May, former CISAC co-director, dubbed "Pief's 'black swans,'" hugely significant but hard-to-predict events.

Wilkening said Panofsky called him on Sept. 23 and volunteered to write up his thoughts on the subject "because he 'had some free time.'"

The workshop was the most recent example of Panofsky's many contributions to CISAC's research and of his dedication to arms control and global security.

"As those who knew him know, Pief was a man of boundless energy and clear thought," Wilkening said. "Pief's passing is a great loss, but his memory serves to inspire many of us to work tirelessly toward those aspirations to which we are truly committed."