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Bill Gates added clean energy and climate change to his agenda in 2010 with a TED talk on the need for “energy miracles,” during which he uncapped a jarful of blinking fireflies in place of the mosquitoes he liberated in a malaria talk the year before.

He’s been ramping up his own commitments since then, and pledged last year to double his investments (to $2 billion) on a host of energy frontiers in the next five years – from new battery and solar technologies to a safer nuclear plant design to tethered, high-flying wind turbines that might harness the power of the jet stream.

And just in case the energy revolution doesn’t happen quickly enough, he’s also investing in systems that might someday be able to remove the long-lasting planet-warming emission from fuel burning, carbon dioxide, from the air at large scale.

Late last year, the man who calls himself an “impatient optimist” broadened his energy quest. Ahead of the Paris climate treaty talks, he helped line up parallel multi-billion-dollar pledges by government leaders and some of the world’s wealthiest investors to accelerate clean-energy science and innovation.

I recently had a 45-minute conversation with Gates in the Seattle headquarters of the Bill and Melinda Gates Foundation to explore what drove him to focus so much time and money in pursuit of energy breakthroughs.

Gates is making a particular effort this year to reach young people. This year’s Gates Letter – the annual mission statement of Bill and Melinda Gates — is shaped as a call to high school students to center their studies and careers on energy innovation and other ways to boost prospects for more than a billion people whose energy poverty locks them into an unhealthy and time-sapping scrabble for existence.

In this campaign and investment effort, Gates is valuably building on the years-long push for an energy revolution by Richard E. Smalley, who shared the 1996 Nobel Prize in Chemistry and, even while fighting a losing battle with leukemia, crisscrossed the nation pressing for a space-shot-scale boost in research and development on technologies that can power planetary prosperity without overheating the climate. (Please take the time to watch the 2003 lecture Smalley gave at Columbia University; this talk shaped my own reporting, helping result in my first long piece, in 2006, on the glaring clean-energy research gap.)

In our conversation, Gates described the next steps for the Breakthrough Energy Coalition that was launched in Paris and surveyed the technologies he sees as most needed.

He also addressed concerns expressed by some energy investors who say energy miracles are already occurring with deployment of today’s solar, wind and other non-polluting energy technologies. (Interestingly, Gates’s gambit in Paris seems to be prompting a friendly competition with other wealthy investors. See the end of the post for some details.)

Here’s the full conversation we had, both the video and a transcript with some light editing for syntax and clarity, some contextual links added by me, some related artwork and culminating reflections:



Video

[If time is tight, watch a six-minute edit here.]

Q.

Do you have a vision for the energy and climate norms that the world could have in 2100, given what you know about the climate system and the energy system?

A.

Well, I have a strong goal that the price of energy should be lower because of the work of the foundation and looking at the lives of the poorest. And so it’s a very big deal that we not push energy prices up too much, so that things like fertilizer, lighting, refrigeration, air conditioning eventually — the kinds of things we take for granted — by 2100 should be available to everyone on the planet. So we need affordable energy.

We certainly want to cut down on local pollution because the understanding of the ill effects of particulates continues to rise. And then at a global level, you don’t want the [climate] perturbation, because it gets you off into a level of uncertainty both about weather and the knock-on effects for ecosystems and species. And you want a limit on the [ocean] acidification because the speed that you’re acidifying is quite rapid versus how quickly evolution can adapt to it. And so, you know, maybe if you wait millions of years, some evolutionary path can build coral reefs in that ocean that you’ve got. But in human time frames that’s a long time to be missing huge parts of the ecosystem.

Q.

What aspect of the climate challenge drives you the most? Many people say sea-level rise is the biggest factor.

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A.

The impacts will be greatest on the poor. Even sea-level rise. Yes, rich cities might have to raise their taxes a little bit, and you might have to move inland a little bit. But if you look at Bangladesh, there are a lot of poor people living in a river delta. That’s not that easy for them to adapt. You certainly have low-lying islands.

To me it’s 70 percent of the world’s poor people are farmers, and they’re barely getting by. And a bad year means that their kid doesn’t have enough nutrition. And so unless we can get their productivity and their resilience up quite dramatically, the increased variance in the weather, including lots of precipitation all at once, they just don’t have the ability to deal with it. When you have resilience, which you have in rich countries, you’re likely to be able to make adjustments.

Q.

Back to Paris, which is where you made a substantial announcement. So could you say now, where we go from here, sort of lay out from that initial grand announcement, what happens next?

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A.

Well for me, it’s pretty easy to think of research and innovation as the thing that’s going change the framework. And my interest in getting that on the agenda goes back quite a ways. I had talked to the United States and France about saying, hey, shouldn’t this be on the agenda? And in fact, in terms of having Paris be novel for driving solutions, you’d do the world a service by getting this onto the agenda. After all, raising R&D is a global public good, to invent something that can solve this problem.

We need to encourage each other. And we even need to think, okay, are there some countries who are specializing, you know, say you want to do [carbon] sequestration. Well, you need a government with the right regulations and incentives, who let’s all the pilot plants and things go on there the right way.

So it really belongs on this agenda, particularly because the big emitters are pretty much one and the same as the countries with research capacity. They can respond by tilting their R&D budget in the right direction. And energy is so unique in terms of how little is spent on R&D, because if you invent something, it’s not going to be deployed in big amounts within a 20-year period.

So yes, it’s wonderful that the countries made that commitment. And at first we thought, you know, if we get five or six countries, including the U.S. and a few big countries, that would be phenomenal. As it was, we ended up with 20 countries, and this is in a time of extremely tight budgets — every European country, Japan, the U.S.

It is very tough. There are very few things that are getting more money. Most of the dialogue is about which things will get less money. So it takes a pretty compelling cause. You know, like when the Ebola epidemic came along. Okay, things related to that got more money.

But only things that really get people’s attention in a big way are allowed to fit that special category. So it was a great announcement. And it was interesting, the idea that the private sector, in terms of high-risk venture investing, would come in and be there so that all we were asking for in this case was the basic research piece. Now, some countries may help with non-research pieces. I think that’s fantastic. But this ask was about the piece that really can only be done at the government level. And we said the group of private investors — we’ll add a lot of institutional investors as well — would bring several billion in so that we can nurture these companies up to a pretty large stage, so that more non-venture type financing would then grab onto them and help with the scale-up.

Q.

Is it anticipated that it’s really going to operate like an endowment?

A.

What we’re planning now is the first five years. And the spending will somewhat grow over the years, because we’ll have more companies that are at a later stage. We are going to look at all the companies that are out there, because there are a few that have promising technologies, but they’re in a place where getting financing is a little bit difficult. So we’re not just going to do start-up companies. We may find a few that are at the stage where getting $50 million or even $100 million would be valuable. And then over the five years, we’ll fully invest money, and then, like most venture funds, we would turn around and say to the investors, hey, if you’re happy with this, yes, we’ll do another fund.

And they’ll look at how well the different things are. We wouldn’t expect all of them to be totally liquid. The turnaround time is not like I.T. where within two years something’s completely gone or it’s a unicorn [an investors’ term for start-ups that reach a billion-dollar valuation] or public.

Q.

Energy is so peculiar that way. I’m sure you’ve talked to Nate Lewis before. He’s got this great line, but it’s a very sobering one, that I put in a story years ago. It’s not like we’re trying to go to the moon. A moon shot is more clear-cut. We’re trying to go to the moon when Southwest Airlines is already flying there, handing out peanuts. In other words, the energy system is there, I can plug my laptop into the wall. So it’s like a substitution for something that’s already there, with these secondary long-term risks. I think that’s what’s impeded the R&D — the government sense that we need to even look at it.

And you’ve seen the graphs of not just the U.S., but the O.E.C.D., when you compare different sectors, it’s unbelievable how little goes into energy research if it’s as important as world leaders say it is.

Are you saying, we wealthy individuals with an investment plan here, we need a hand-off. We need you to work on this, too. It’s kind of like a quid pro quo thing?

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A.

Well there’s always been a tradition that certain advances got funded by individuals. I mean, somebody endowed a Lucasian Professorship for Newton to take. And a lot of good science happened by private donors caring about it. Here, we have this imperative where the impact—if you talk in monetary terms, although there are other ways of measuring it that are probably more valuable — you’re talking about trillions of dollars.

It won’t be as fast. But we do expect to make money out of this thing. If you can drive a new approach, then the energy economy is absolutely gigantic. Now, getting it scaled up fast enough, so that you benefit from your invention or your trade secrets, that is tricky. But it’s great that we have that incentive. The financial incentive is to get it out and scaled quickly, and the climate benefit requires that same mentality.

Q.

John Holdren, the science advisor to President Obama, way before he was in that office, articulated how little we spend in a way that was effective. He said a two-cent rise in the gasoline tax triples our R&D money in this country. Recently I asked him by email to update the numbers, and he said the appropriation for energy R&D the last several years has been $3.6 billion, roughly. And he said that it’s more like a doubling of research, if you have a two-cent rise in the gas tax.

Is there a way to make that case to the American people that hasn’t been made? You talk to people of all political stripes, I assume. Have you found a way to get traction with the logic of that?

A.

Well, research hasn’t been discussed much, but I do think it has a lot of appeal. Everyone wants great companies that are leading the way. We do have amazing universities where the basic technology, the material science, the simulation. You know, the I.Q. around the world large is very strong on this — to make the case to the U.S. that it should be a leader in doubling its budget. That was pretty important. I don’t think if the U.S. wasn’t participating, it would be easy to get critical mass. Because even though we underspend, we are about 50 percent of all of the energy R&D spending that gets done.

I think everybody can get excited when they hear there are really ideas out there. And when you talk about basic research, you get away from the somewhat partisan divide about what’s the role of government. Nobody would say it was zero, but you’d get quite a range of views of how much the government ought to try and help out at that later stage.

And so I think this one, now that it’s been highlighted as being so important, it you know, creates jobs in the company that allocates the R&D, it creates business opportunity in the country. And as you say, it’s not relative to the size of the energy market or what’s at risk here. It’s actually very, very small. You know, capitalism in general underinvests in research because the benefits to society are way more than whoever takes the risk and does the invention gets. And energy is just particularly dramatic in that. In fact, I.T. and health, people are spoiled by those, because those have pretty strong research models, both at the government level and at the private level.

Q.

Circling back to Paris, could you lay out the general sectors you personally are interested in, and inevitably these investments will be in? Can you remind people what some of the basic concepts are that are out there?

A.

The range of possibilities for getting an energy breakthrough that is something that will be cheap and clean, there’s quite a few ways to do that. Ah, in the nuclear space there’s fusion; there’s fission.

Within wind, you’ve got high [altitude] wind that only a little bit’s been done in. You have offshore wind, you have whatever improvements you can do to onshore wind, which you know, will likely be a workhorse of the overall system. Then in solar, you have solar electric, which has gone the furthest. You can do a lot more there. You have solar thermal, which has some nice characteristics, because storing heat is easier than storing electrons.

And then you have solar chemical, which is where — without using a photosynthetic process; you’re using a de novo process — photon energy equals some type of hydrocarbon. Think of oil dripping off of a solar panel type thing.

That’s a paradigmatic example because it is not ready for a start-up, but there are some particular problems in terms of material structures and simulation that, if the right research was done, even over the next two or three years, then you could have a set of start-ups that would go into that area.

High wind is another one where the challenges are, to some degree, control and materials challenges. This is the golden age of actually rationally designing materials, whether it’s for tensile strength or for catalytic capabilities. And if you can look at that area and say, okay scientists, here’s what we need, then you can stimulate a lot of good work. And for us it’s a little bit like what we do at the foundation where we take a disease problem and then we try and make sure the scientists who might — even if they don’t know the disease — have some tool that would help stimulate them to get involved.

Biofuels is a category where you’re either taking natural photosynthesis or modifying natural photosynthesis to get much higher efficiencies, and there’s quite a few, you know: trees, grasses, algae. If you’re taking current photosynthesis, then there’s many ways to do cellulosic processing, none of which should have gotten into the large-scale mainstream, but there’s a lot of promise that that might happen.

And when we think about climate, we have to think about more than electricity. We have to make materials. There’s steel, aluminum, cement, plastic, paper — all of which are big processes we’re dependent on, some of which directly generate CO2, like cement production, and a lot of which are big industrial users of electricity or energy. We also have the entire land use, agricultural, livestock area, which is a very significant CO2 emitter.

A little bit of the trap people get into is they think, okay if we’re meeting some 2030 goal, we must be on the way, because we just do more of what we did. Well, a lot of things you do, like, take [away] coal and build natural gas, for your 2050 goal, that’s actually a step backwards because that gas plant is at a higher CO2-per-kilowatt-hour than you’re going to want to have in 2050. So you thought, oh what a great thing we just did. But in fact it doesn’t scale to the sort of near-zero [emissions technology] that we need to achieve.

So when you think of the industrial economy, getting 20 or 30 percent out of that by pushing up recycling, labeling things, that’s easy. But you have to plan today for meeting the large target. You don’t just get to get partway there and say, oh well someone else will figure out how to make steel or, you know, let’s pretend we don’t need to make a lot of steel.

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Q.

One of the things that frustrated me about Paris was that the whole discussion was about that 2020 to 2030 period. But all of those trajectories for that short period rely on this unbelievably steep dip that has to happen later. There was a lack of full disclosure that we don’t know how to do that yet. And that’s where the R&D has to come in.

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A.

Yeah, and people like David McKay have tried to get people to say, hey, we only have so many ways to make energy. And have models — he did it for the U.K. with “Sustainable Energy Without the Hot Air.” But there are not a lot of ways to get that scale of energy. And there are geographies like Japan. You know, where is their energy going to come from? People tend to want sovereign control of their energy supply. And so you run into geographic realities. What technologies are going to fit there?

Q.

I know you have an interest in CO2 removal – taking it out of the atmosphere and stashing it long term. Vaclav Smil, who we both read and talk to, talks about the scale issue. He has said you would need the same infrastructure we have all around the Earth taking oil out of the ground to put a waste gas in the ground.

CO2 removal is actually implicit in the models that the I.P.C.C. provided for the treaty process, to get that deep dive. But is it realistic to get that gigaton kind of outcome?

A.

Well there’s a couple ways that it could come in. Poor countries, even if we figure out how to take livestock and land use in rich countries and get that down to zero, there’s going be a lot of emissions out of poor countries. And we shouldn’t force them not to use hydrocarbons. People actually get confused in climate and think this is bad for poor countries so let’s get them to do expensive intermittent energy systems and then it’s okay.

No, developing and truly poor countries – not China or India – they are a rounding error. So anything you do with their energy systems is a hobby, unrelated to climate change. I mean, maybe you could bring some power there, but they should grab onto the cheapest solution.

And so the rest of the world has to be at true zero or even, under some models, it’s a negative number, which is where you get to capture. A lot of the systems design that people are looking at – like Christopher Clack — even if you can get the renewables up to 80 percent, then you have a piece there probably natural gas “peakers” [power plants that run in periods of high electricity demand], at least based on current technology, are way cheaper than any [energy] storage.

So doing carbon sequestration out of a natural gas [power plant] flue is a lot easier than out of a coal flue, because there isn’t the sulfuric acid. And there’s very little going on with that, but we may need that as part of a solution for that backup peaker 20 percent. Or if you have emissions taking place far away, in the poor countries, the idea that you could do free air capture, like Carbon Engineering is trying to do and a few other people are trying to do — that would have to be part of the mix.

So actually, building prototypes now and saying, okay, how hard is it to do that carbon capture at scale, it’s great that that work is going on. The initial plants will be at very high prices — on the order of $100 per ton, which is way above even the highest CO2 tax in the world.

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Q.

There are some pretty cool ideas out there. I was just at Arizona State, for the first time seeing Klaus Lackner’s work there. He has this spongy looking material that captures CO2 in dry air. You put it into a greenhouse in a moist environment and it liberates the CO2. So he’s developing a prototype like that. And it’s exciting to see minds working on these problems.

I’d like them to be more visible, more integrated perhaps into how kids are learning.

You and I grew up in the space race, you know, it was a no-brainer. Science was all around us. But do you see a way to make this story more pervasive?

A.

Well, I definitely think we need to take the dreams, like for air capture of CO2, and get those out there and make it concrete. You know, or high wind. I mean super-high altitude, the jet stream, which is a very constant source, and a large source. But it’s just very difficult to design that system. Get people thinking about those things and realize, hey, we need some inventions, and draw young people in.

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Q.

I’ve seen other experiments in the education arena. There was a woman [Ozgem Ornektekin] who was the sustainability chief for the New York City school system for a while. And she had gotten some federal funding to put new energy management systems in the school buildings. They started realizing they didn’t have enough people in New York trained to run these systems. So they created this High School of Energy and Technology. And it’s kind of geared to getting young people into the heating-cooling arena. One of the things I was incredibly excited to see there is that they go on a boiler room tour as part of their education. And the custodian is their teacher for the day. He shows them this boiler room, where just 20 years ago, coal was hand shoveled into the furnace. And now it’s oil.

And I would like a boiler room tour in every school in America. You don’t have to charter buses. There are no permission slips, and you start to understand an energy system within a school. It’d be great to see innovation on that front. Maybe not as much as the innovation in laboratories for photovoltaics. I’m a communicator and an educator, so I’m biased — but I think there’s a lot of potential in that arena for innovation, as well. You should go on that boiler room tour. It’s a great template.

Every day I wake up with this issue, like we all do, with a sense of optimism when I see an exciting innovator, and pessimism when I feel the weight of inertia. In 2013, the Bloomberg administration had this statistic where they realized, 75 percent of New York City’s greenhouse gas emissions are from energy in buildings. And 80 percent of the buildings that exist in 2050 in New York City already exist. And so that says you can have your shining visions of the future and transformative, energy pathways. But you still have to deal with window by window, door by door retrofitting.

A.

Not really. Not if your electricity coming in is zero CO2. If the electricity system isn’t about zero CO2, there’s no way to get there. I mean, just ignore the U.S. Assume we could cut some dramatic amount. Just look at India. They will be using over 10 times as much energy. And, yes, some of those light bulbs will be more efficient. Some of those refrigerators will be more efficient. But they will be using more kilowatt-hours. There’s not any doubt. A lot more. The more the better. And so the generation system really has to do the magical work here.

And there are generation systems. I mean, nuclear has got lots of lots of problems, but it does not emit CO2. Hydro, if you manage it properly and you’re working with a reservoir and everything, it doesn’t have to emit CO2.

But I certainly agree with you that this is a problem that you can go from thinking it will be solved to thinking that it won’t be solved.

And even some of the people who think it’s easy to be solved can be frustrating to me, because then the idea of oh no we don’t need to invent anything, we just need to get rid of evil utilities that aren’t paying 50 cents a kilowatt-hour for rooftop solar, and as soon as we get them to just realize they should go bankrupt, you know, boom, this thing is solved. It is a very hard problem to solve, because energy systems have to be reliable. And if you’re a utility, you are supposed to buy low-cost energy on behalf of those consumers. Utilities are not there to spend money on global public goods, which is what CO2 reduction is.

Q.

You and I both are criticized sometimes by people who feel that too much of a focus on these — some call them moon shots, whatever you want to call it, the breakthroughs — this distracts from what they argue is the ability to do mass deployment now. What do you say in a situation like that? Do you have a way to balance that rhetorically?

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A.

Well India is paradigmatic. And you know, it’s only 1.4 billion people. So they have to electrify. That’s why children don’t die. They need to be able to refrigerate their food and heat and cool. And so if you think you have a solution that doesn’t slow down India improving the lives of their people to be almost as good as what we take for granted, if you think today’s technology solves the India problem with no price premium, no reliability problem, then great. Go to India, and it’s a capitalistic market there. Go ahead and do that. That is when you’ll know that we’re on our way.

Then you’re not saying to them, trade off between these two things. Yes, the United States could afford for energy to cost a lot more than it does today. Europe can afford for energy to cost a lot more. Japan can afford for it to cost a lot more. But the future CO2 emitters are not going to pay some meaningful premium, nor are they going to give up total reliability. Their hospitals want energy; their factories want energy all the time.

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Q.

One thing I wrote a few years ago about this grand question is that it seems to require a quirky mix of urgency and patience. I don’t know how you grapple with that yourself. In your career, have you had other issues where you had to have urgency and patience at the same time. Is that every day?

A.

Well I call myself the impatient optimist, because I want things to go faster. With something like an HIV vaccine, you know, there are a lot of dead ends. But you’ve got to believe that eventually you’re going to find one and you want to pursue a lot of different things. And I’m very optimistic, you know, we’re getting smarter all the time, ah, about how to do that. So it really won’t happen overnight.

You know, I’m investing in a fission company. And the best case is that we have our pilot plant built by 2023, and that by 2030, this fourth-generation inherently safe design with all sorts of nice characteristics, including cost, becomes the standard for all nuclear builds from that point forward. That’s the best case for this amazing, brilliant Terrapower design [this was said with the knowing smile of a pitchman].

Well, in software, nobody at Microsoft is sitting there saying, oh yeah, what’s the 2040 thing going look like? It’s a ridiculously long time period, even for a health-care type intervention, to try and think, hey we’re doing this great work so that we have this tool for 25 years from now.

But for good reason — safety tests and capital costs and just the time it takes to build large-scale things — that’s the time frame that it’s in. If that is part of the solution, which is hard to say, I’m really glad the work is being done. It has some meaningful chance of being able to help us with the climate problem.

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Reflections

After 30 years of learning (and unlearning) about climate change science and policy, as many know, I’ve tended to give extra weight to the argument for greatly intensified research pressed by Gates, and before him Richard Smalley, John Holdren, Martin Hoffert and Ken Caldeira, the Deep Decarbonization team, the Breakthrough Institute and many others.

This is mainly because I so often see a natural human bias toward the here and now — the low fruit — that tends to downplay the need to work now to build the intellectual and technical capacity for bigger changes later.

But Gates’s research and development argument is inevitably just one facet of a much more variegated energy agenda that provides plenty for everyone to pursue. Click back to this piece from a climate science and policy meeting in Paris last July to get the idea: “Varied Paths to a Sustainable Human Relationship With Earth’s Climate.”

Behind edge-driven debates, almost everyone I’ve met who’s seriously pursuing a post-fossil energy future would like all of the above — more science literacy, more energy awareness, more energy access now for those in deep poverty, lower costs for energy all around and some kind of price on the most polluting fuels (see the Niskanen Center’s “Conservative Case for a Carbon Tax” to see the breadth of support).

To my eye, for example, as important as edge-pushing innovation is work facilitating the rapid spread of cleaner energy choices in poor places, many of which are unlikely ever to be linked to a conventional power grid. For a valuable discussion of what’s possible on the ground now in accelerating electricity access in places without any options, watch the conversation I had in 2014 with Harish Hande, a renewable-energy entrepreneur in India, on the entrepreneur’s role in solving energy poverty:

And there’s plenty of room for financial and policy innovation, as well. Revisit my 2013 conversation with Billy Parish, a founder of Mosaic, a company through which small investors can earn interest financing the installation of solar panels, and Andreas Karelas, the executive director, of RE-volv, a nonprofit revolving fund also financing solar projects. These young financial and social entrepreneurs have a critical role to play.

With that in mind, one result of Gates’s research campaign appears to be some constructive competition from other wealthy investors pursuing financial, instead of technological, breakthroughs.

On my visit to Seattle, I ran into Adam Wolfensohn, co-managing partner of the investment firm Encourage Capital. He is among those concerned that the pursuit of energy miracles, if seen as the only path, might weaken support for other efforts.

“Radical innovation in low-carbon energy technology is critical to long term climate mitigation,” Wolfensohn said. But he said he and others are exploring the creation of an investors’ coalition, “complementary to the Gates initiative,” aimed at overcoming a different set of barriers to progress.

“Financing renewables is fundamentally different than fossil energy,” he said, noting, for example, that different investment vehicles are needed when there is a high capital cost up front and extremely low costs for energy in the end. “Energy efficiency,” he added, “which is such a key part of the solution, is financed from avoided cost as opposed to revenue, which is its own challenge.”

He described a host of new tools and approaches to financing that could, with an innovative push, “overcome those barriers to deployment that lie solely with the financing market, not with the technology.”

Facing what many call a “super wicked” challenge, a diversity of responses is vital.

As Maurice Sendak put it, let the wild rumpus start!

Twitter postscripts |

Here’s an excerpt from the Gates Letter that helps define terms — a vital first step before debating the merits of different policies:

Defining terms good start in hashing out clean-energy paths. @BillGates’s take on “miracles” https://t.co/E3suy2dIKy https://t.co/W3UORWRUos — Andy Revkin (@Revkin) 23 Feb 16

Here’s a tweet of mine making the point that innovation, in this case a fresh business model at Selco in India, can fast-forward improvement in people’s lives in rural or off-grid communities even as urban power systems evolve:

Solar and Livelihood – Solar Powered Sewing Machine being used in Manipur, India //t.co/iXzHVX1QfZ — Harish Hande (@Harishhande) 17 Dec 14

Here a tweet by Michael E. Mann, the Penn State climate scientist and author, of a piece by Gates’s most persistent critic, Joe Romm, a physicist, former Energy Department official and climate campaigner:

“Bill Gates Is Wrong That We Need ‘Energy Miracles’ ” by Joe Romm for @ClimateProgress: https://t.co/BNbrBIUrRm — Michael E. Mann (@MichaelEMann) 23 Feb 16

Here’s a good tweeted question from David Lea, a paleoclimatologist at the University of California, Santa Barbara:

.@BillGates Can oil majors be part of the clean-energy innovation agenda, directly or indirectly, or are they hopeless dinosaurs? @Revkin — David Lea (@DavidWLea) 23 Feb 16

Ezra Klein did a much more wide-ranging interview with Gates and his Vox.com colleague Brad Plumer offered this comment (explore the Twitter flow thereafter):