本文转自MIT Technology Review 发布的题为“The daunting math of climate change means we’ll need carbon capture”的报道。

由一位行业领先的专家讲述了如何在经济上和规模上做到这一点。

作者：James Temple

发布日期：2018-04-24

原文链接：https://www.technologyreview.com/s/610927/the-daunting-math-of-climate-change-means-well-need-carbon-capture/

At current rates of greenhouse-gas emissions, the world couldlock in 1.5 ˚C of warming as soon as 2021, an analysis by the website Carbon Brief has found. We’re on track to blow the carbon budget for 2 ˚C by 2036.

Amid this daunting climate math, many researchers argue that capturing carbon dioxide from power plants, factories, and the air will have to play a big part in any realistic efforts to limit the dangers of global warming.

If it can be done economically, carbon capture and storage (CCS) offers the world additional flexibility and time to make the leap to cleaner systems. It means we can retrofit, rather than replace, vast parts of the global energy infrastructure. And once we reach disastrous levels of warming, so-called direct air capture offers one of the only ways to dig our way out of trouble, since carbon dioxide otherwise stays in the atmosphere for thousands of years.

Julio Friedmann has emerged as one of the most ardent advocates of these technologies. He oversaw research and development efforts on clean coal and carbon capture at the US Department of Energy’s Office of Fossil Energy under the last administration. Among other roles, he’s now working with or advising the Global CCS Institute, the Energy Futures Initiative, and Climeworks, a Switzerland-based company already building pilot plants that pull carbon dioxide from the air.

In an interview with MIT Technology Review, Friedmann argues that the technology is approaching a tipping point: a growing number ofprojects demonstrate that it works in the real world, and that it is becoming more reliable and affordable. He adds that the boosted US tax credit for capturing and storing carbon, passed in the form of the Future Act as part of the federal budget earlier this year, will push forward many more projects and help create new markets for products derived from carbon dioxide (see “The carbon-capture era may finally be starting”).

But serious challenges remain. Even with the tax credit, companies will incur steep costs by adding carbon capture systems to existing power plants. And a widely cited 2011 study, coauthored by MIT researcher Howard Herzog, found that direct air capture will require vast amounts of energy and cost 10 times as much as scrubbing carbon from power plants.

以下是采访内容：

(This interview has been edited for length and clarity.)

In late February, you wrote a Medium post saying that with the passage of the increased tax credit for carbon capture and storage, we’ve “launched the climate counter-strike.” Why is that a big deal?

问题：在2月下旬，你说随着碳捕获和储存税收抵免的增加，我们“发起了气候反击”。为什么这是一个大问题？

回答：It actually sets a price on carbon formally. It says you should get paid to not emit carbon dioxide, and you should get paid somewhere between $35 a ton and $50 a ton. So that is already a massive change. In addition to that, it says you can do one of three things: you can store CO2, you can use it for enhanced oil recovery, or you can turn it into stuff. Fundamentally, it says not emitting has value.

As I’ve said many times before, the lack of progress in deploying CCS up until this point is not a question of cost. It’s really been a question of finance.

The Future Act creates that financing.

I identified an additional provision which said not only can you consider a power plant a source or an industrial site a source, you can consider the air a source.

Even if we zeroed out all our emissions today, we still have a legacy of harm of two trillion tons of CO2 in the air, and we need to do something about that.

And this law says, yeah, we should. It says we can take carbon dioxide out of the air and turn it into stuff.

At the Petra Nova plant in Texas, my understanding is the carbon capture costs are something like $60 to $70 a ton, which is still going to outstrip the tax credit today. How are we going to close that gap?

问题：在得克萨斯州 Petra Nova工厂，我的理解是碳捕集成本大约是每吨60美元到70美元，仍将超过税收抵免。 我们将如何缩小差距？

回答：There are many different ways to go about it. For example, the state of New Jersey today passed a 90 percent clean energy portfolio standard. Changing the policy from a renewable portfolio standard [which would exclude CCS technologies] to a clean energy standard [which would allow them] allowed higher ambition.

In that context, somebody who would build a CCS project and would get a contract to deliver that power, or deliver that emissions abatement, can actually again get staked, get financed, and get built. That can happen without any technology advancement.

The technology today is already cost competitive. CCS today, as a retrofit, is cheaper than a whole bunch of stuff. It’s cheaper than new-build nuclear, it’s cheaper than offshore wind. It’s cheaper than a whole bunch of things we like, and it’s cheaper than rooftop solar, almost everywhere. It’s cheaper than utility-scale concentrating solar pretty much everywhere, and it is cheaper than what solar and wind were 10 years ago.

What do you make of the critique that this is all just going to perpetuate the fossil-fuel industry?

问题：你如何评价这一切将会延续化石燃料行业？

回答：The enemy is not fossil fuels; the enemy is emissions.

In a place like California that has terrific renewable resources and a good infrastructure for renewable energy, maybe you can get to zero [fossil fuels] someday.

If you’re in Saskatchewan, you really can’t do that. It is too cold for too much of the year, and they don’t have solar resources, and their wind resources are problematic because they’re so strong they tear up the turbines. Which is why they did the CCS project in Saskatchewan. For them it was the right solution.

Shifting gears to direct air capture, the basic math says that you’re moving 2,500 molecules to capture one of CO2. How good are we getting at this, and how cheaply can we do this at this point?

问题：基本的数学表明你正在移动2,500个分子来捕获一种二氧化碳。 我们在这方面有多优秀，在这一点上我们能做到多便宜？

回答：If you want to optimize the way that you would reduce carbon dioxide economy-wide, direct air capture is the last thing you would tackle. Turns out, though, that we don’t live in that society. We are not optimizing anything in any way.

So instead we realize we have this legacy of emissions in the atmosphere and we need tools to manage that. So there are companies like Climeworks, Carbon Engineering, and Global Thermostat. Those guys said we know we’re going to need this technology, so I’m going to work now. They’ve got decent financing, and the costs are coming down and improving (see “Can sucking CO2 out of the atmosphere really work?”).

The cost for all of these things now today, all-in costs, is somewhere between $300 and $600 a ton. I’ve looked inside all those companies and I believe all of them are on a glide path to get to below $200 a ton by somewhere between 2022 and 2025. And I believe that they’re going to get down to $100 a ton by 2030. At that point, these are real options.

At $200 a ton, we know today unambiguously that pulling CO2 out of the air is cheaper than trying to make a zero-carbon airplane, by a lot. So it becomes an option that you use to go after carbon in the hard-to-scrub parts of the economy.

Is it ever going to work as a business, or is it always going to be kind of a public-supported enterprise to buy ourselves out of climate catastrophes?

问题：为使我们自己摆脱气候变化的灾难，它是否会作为一个商业，还是它总是成为一个公共支持的企业？

回答：Direct air capture is not competitive today broadly, but there are places where the value proposition is real. So let me give you a couple of examples.

In many parts of the world there are no sources of CO2. If you’re running a Pepsi or a Coca-Cola plant in Sri Lanka, you literally burn diesel fuel and capture the CO2 from it to put into your cola, at a bonkers price. It can cost $300 to $800 a ton to get that CO2. So there are already going to be places in some people’s supply chain where direct air capture could be cheaper.

We talk to companies like Goodyear, Firestone, or Michelin. They make tires, and right now the way that they get their carbon black [a material used in tire production that’s derived from fossil fuel] is basically you pyrolize bunker fuel in the Gulf Coast, which is a horrible, environmentally destructive process. And then you ship it by rail cars to wherever they’re making the tires.

If they can decouple from that market by gathering CO2 wherever they are and turn that into carbon black, they can actually avoid market shocks. So even if it costs a little more, the value to that company might be high enough to bring it into the market. That’s where I see direct air actually gaining real traction in the next few years.

It’s not going to be enough for climate. We know that we will have to do carbon storage, for sure, if we want to really manage the atmospheric emissions. But there’s a lot of ground to chase this, and we never know quite where technology goes.

In one of your earlier Medium posts you said that we’re ultimately going to have to pull 10 billion tons of CO2 out of the atmosphere every year. Climeworks is doing about 50 [at their pilot plant in Iceland]. So what does that scale-up look like?

问题：在你之前的一篇文章中，你说过我们最终将不得不每年从大气中排放100亿吨二氧化碳。 Climeworks在冰岛的试点工厂工作了大约50人。 那么这种扩大规模是什么样子？

回答：You don’t have to get all 10 billion tons with direct air capture. So let’s say you just want one billion.

Right now, Royal Dutch Shell as a company moves 300 million tons of refined product every year. This means that you need three to four companies the size of Royal Dutch Shell to pull CO2 out of the atmosphere.

The good news is we don’t need that billion tons today. We have 10 or 20 or 30 years to get to a billion tons of direct air capture. But in fact we’ve seen that kind of scaling in other kinds of clean-tech markets. There’s nothing in the laws of physics or chemistry that stops that.