Hydrogen is Sexy
lawrence fisher writes about business for The New York Times and other publications.
Published July 15, 2016.
Environmentalists targeting fossil fuels have a catchy slogan – Keep it in the ground! – which has been trumpeted by organizations ranging from Greenpeace to The Guardian. Perhaps something similar is needed to jump-start carbon capture, the trapping and storage or repurposing of carbon dioxide released in burning fossil fuels as well as in a host of industrial processes. So here you are, free of charge: Suck it up!
In truth, carbon capture and storage (CCS) needs more than a slogan to gain traction. The reluctance to add it to the toolbox of fixes for climate change is ironic, for with each passing year the case for CCS grows more compelling. A 2015 study conducted at University College London and published in
Nature identified fossil fuel reserves that must not be burned to keep the global temperature rise since pre-industrial times below 2 degrees Celsius (3.6 degrees Fahrenheit). It included over 90 percent of U.S. and Australian coal and almost all the fuel that could be extracted from Canadian tar sands. All told, half of global natural gas reserves and a third of oil must remain unused.
These are very ambitious targets. The global leaders who met in Paris earlier this year pledged to do their part. But developing countries (led by China and India) continue to build new coal plants, while oil and gas companies still spend billions of dollars a year to identify new reserves. And the International Energy Agency, a multilateral agency based in Paris, estimates that fossil fuels will still account for about 40 percent of primary energy use in 2050.
If the IEA is right, atmospheric carbon will way overshoot the level tied to the 2-degree temperature rise. Hence the relevance of CCS, which according to the IEA is the only technology able to deliver significant reductions in emissions from the use of fossil fuels. And, happily, what long looked like a fantasy cooked up by the visionaries who imagined that nuclear energy would soon be too cheap to meter, is entering the realm of economic viability.
Actually, carbon capture has a lot going for it. For starters, it works: 15 projects are already in operation around the world. It can be retrofitted to existing power plants burning fossil fuels. It can also capture CO2 from a variety of manufacturing processes, including the production of steel, cement and chemicals, that collectively account for about 25 percent of global emissions. And did I mention that it is affordable? At $100 or less per ton, capturing and storing carbon from industrial emissions is cheaper than saving an equivalent ton by switching electricity production from fossil fuels to solar.
The catch – and of course there's a catch – is that nobody seems to love carbon capture. On the left, climate change activists lobby almost exclusively for renewables and energy conservation – the eat-your-spinach approach. On the right, at least in the United States, climate change is still claimed to be a hoax perpetuated by liberals who don't want Americans to drive SUVs or mine coal in Appalachia. Even in Britain, where conservatism doesn't require science denial, the Cameron government has eliminated financing for two demonstration power plants employing CCS, along with ending subsidies for onshore wind power.
It is human nature to seek silver bullets even if a shotgun approach is more practical – as when your financial adviser recommends a diversified portfolio of low-cost index funds when what you really crave is a tip on the next Google or Facebook. So it seems with climate change and the rush to deploy renewables to the exclusion of other solutions, like a combination of natural gas combustion cleaned up with CCS.
But reality is just beginning to bite: there is the first hint of an awakening among environmentalists that achieving carbon reduction goals within the short time left before major economic and social dislocation becomes inevitable will require an "all of the above" strategy. Indeed, some are willing to go further than the distasteful notion of CCS. Long-time emissions warriors, including Stewart Brand of
The Whole Earth Catalog fame and James Hansen, the Columbia University scientist who first brought public attention to climate change, are even urging construction of new nuclear power plants, which don't emit CO2 – but that's another story.
What CCS Does, How It Works
The bulk of research and most of the pilot plants around the world focus on post-combustion carbon capture. This is primarily applicable to fossil-fuel-based systems like conventional coal-fired power plants, where the powdered fuel is burned with air to produce steam that drives a turbine generator to produce electricity. The carbon dioxide is captured from the flue gas after fuel combustion, using a chemical absorbent. The captured CO2 can then be put to productive uses – everything from injecting it into old wells to help recover residual oil to carbonating soft drinks. But in a world in which carbon capture was scaled up sufficiently to make a real dent in atmospheric carbon, the amount of CO2 yielded from power generation would far exceed prospective need.
So all that captured carbon would have to go somewhere other than back into the atmosphere. Most schemes call for the CO2 to be liquefied for easier transport, and then stored, or "sequestered," in geologic or oceanic reservoirs. Not surprisingly, a number of caveats apply:
- the storage period would need to be long – as in hundreds to thousands of years
- the cost of storage, including liquefaction and transportation to the site, would need to be low enough to be practical
- the risk of accidents would need to be low
- the collateral adverse environmental impact would need to be modest
- the storage method would need to meet legal criteria.
In light of these criteria, suggested by the Massachusetts Institute of Technology Laboratory for Energy and the Environment, it would hardly be a piece of cake. But it is doable. In Norway, Statoil, the national oil company, has been injecting and storing about one million tons of CO2 per year from a natural gas processing facility for nearly 20 years at its Sleipner project in the North Sea.
Sleipner doesn't produce power, however. The honor for the world's first commercial-scale carbon dioxide capture and storage power plant goes to the coal-fired Boundary Dam in Saskatchewan, Canada, which came online in October 2014. Two additional projects in the power sector – the Kemper County project in Mississippi and the Petra Nova Carbon Capture Project in Texas – are scheduled to start this year. Shell Oil's Quest CCS project, launched in Alberta, Canada, in November 2015, is the world's first CCS project to reduce emissions from one stage in the refinement of tar sands into fuel.
All of these projects capture CO2 at the source, whether in a power plant flue or in the process of extracting oil and gas. But there have also been some highly publicized efforts to suck the gas directly out of the atmosphere. These include the Canadian startup Carbon Engineering, formed in 2009 with $3.5 million from Bill Gates and others, and the audaciously named Global Thermostat in New York, which is backed by Seagram's scion and former Warner Music chief executive Edgar Bronfman Jr. Both companies received a lot of ink a few years back from The New York Times, The Washington Post and the like. But they have been much quieter lately, and declined to talk to this reporter. Skeptics say their approach is simply impractical.
"If you're talking about capturing CO2 from the air, that's garbage," said Howard Herzog, director of the Carbon Capture and Sequestration Technologies Program at MIT. "From a power plant, it's expensive; from the air, it's prohibitive. It's the concentration of the CO2: in a power plant, it's about 10 percent concentration; in the atmosphere, it's diluted 300 times."
Getting it Built, Getting it Paid For
MIT maintains one of the most exhaustive databases of carbon capture, and provides an interactive Google map on its website showing the location of all the active carbon capture and storage projects worldwide. These include power-plant CCS projects, non-power CCS projects and CCS pilot projects. The database is notably not dominated by Silicon Valley startups with celebrity investors, but rather features a list of tried-and-true names from the energy and heavy machinery industries: Shell, General Electric, Siemens, Schlumberger.
"A few companies, like Shell, are still very active in CCS," Herzog said. "The utilities can't afford it, and the coal companies are a total wreck. Low natural gas prices have sort of crossed over all our sins. The pipeline for new big projects is drying up."
In this country there's too much polarity in the political system, he laments. "The right denies the problem; the left hates fossil fuels, and even though that's 80 percent of our power, they say we're going to replace it all."
There has been little discussion of climate change in the current presidential campaign, though the Democratic contenders did give the occasional shout-out to renewables, which plays well with their base. This is in sharp contrast to President Obama's 2008 campaign, in which he made frequent mention of multiple methods for reducing CO2, including CCS. The prospect of a cap-and-trade system, which would have made cost-effective CCS self-financing, seemed very real.
After his election, the CCS research, development and deployment budgets were effectively tripled for the next seven years with the injection of $3.4 billion of stimulus funds. Then came the Republican sweep of 2010, and instead of cogent climate policy, we got snowballs in the Senate.
In Britain, five years of a Tory-Liberal Democrat coalition government ended in 2015 with the Conservative party winning a clear majority in the House of Commons. British conservatives, and indeed most conservatives in most countries other than the United States, do not deny climate change. But they're not keen to spend money combating it, either. As the Tory manifesto put it: "We will cut emissions as cost-effectively as possible, and will not support additional distorting and expensive power sector targets." In practice, that has meant the continued development of North Sea oil and gas, the end of subsidies for onshore wind power and the elimination of CCS funding.
As Jenifer Baxter, head of energy and environment at the Institution of Mechanical Engineers in London, explains:
For a long time in the UK there was a competition running for £1 billion [about $1.45 billion], for a bit over two years to support innovation and demonstration projects in CCS and their application to commercialization. Last year, in budget review after four years of this program running, the government canceled it. This meant that the two power stations that had been working on it withdrew from carbon capture and storage. Industry then withdrew because it was very expensive anyway and the economics for them were already difficult.
What Could Possibly Go Wrong?
No power source is without externalities. Carpeting the country with photovoltaic cells has an environmental – and aesthetic – impact. Wind turbines kill birds and can mess up idyllic views. CCS has its own problems. First is the issue of where to put all the captured carbon, and the same people who worry about climate change have major reservations about pumping CO2 deep into the earth or piping it to the bottom of the sea. Critics also say that the economics of retrofitting CCS to existing coal plants do not add up, especially at a time when coal is fading, and that the capital needed to build new natural gas power plants is better invested in wind, solar and innovations in energy storage that are inherently carbon-free.
"The reality is we haven't seen a lot of successes" for CCS, said Rachel Cleetus, lead economist and climate policy manager at the Union of Concerned Scientists. "Take the Kemper Plant [in Kemper County, Miss.], which a lot of people hoped would be the first demonstration at scale. They're up to nearly $7 billion in costs and they still haven't come online. When you take that and you imagine the level CCS would need to come in at, and the time frame we have to make a difference, scaling it up is a real challenge."
During the 2008 election, President Obama often spoke of something called "clean coal," which was really code for coal-fired power with carbon capture. But in the years since, as natural gas prices have dropped significantly, the coal industry has gone into steep decline. New natural gas plants offer the opportunity to add CCS. But that adds cost as well, and without government subsidies or tax incentives, it doesn't happen. Current policy includes various tax breaks and incentives for renewables, but not for CCS.
"Retrofitting is inevitably more expensive than actually designing plants from the get-go with CCS," Cleetus said. "But we aren't seeing that in the market to the extent that new natural gas build-outs are happening. What we're seeing is that wind and solar additions are outpacing every other source, and that includes natural gas."
Cleetus says that market forces and the technology's own externalities hamper CCS adoption more than public policy does. "The Department of Energy does have a number of loan guarantee programs for these projects," she said. "Kemper had one of these grants. But the reality is we're seeing cost escalation and project delays. In renewables, we're seeing cost declines. The trend is not going in a favorable direction with CCS. Also, CCS, as currently configured, is quite a water hog. We are in an increasingly water-constrained world, so we have to find a way for technologies like this to work in that environment."
Another knock on CCS is that it has been hyped in combination with biomass energy (BECCS) in the International Panel on Climate Change model for achieving negative emissions. In a scathing OpEd piece in The Guardian, Tim Kruger and Steven Rayner, both scientists at Oxford University, and Oliver Geden, head of the EU division at the German Institute for International and Security Affairs, wrote that relying on this pairing of technologies "to deliver us from climate change is to demonstrate a degree of faith that is out of keeping with scientific rigor."
"Technically, there are serious doubts about the ability to sequester the vast quantities of carbon dioxide that are implied in the models," they wrote. "Economically, without a substantial carbon price [through a tax or a cap-and-trade system], the costs would be much higher than competing power-generation technologies. Environmentally, growing such volumes of biomass would have profound effects on biodiversity. Socially, the use of land for BECCS would restrict agriculture – contributing to substantial increases in food prices."
But even as these scientists question the viability of BECCS, others are exploring still more ambitious alternatives. Why sequester CO2 at all, when it can be a viable commodity in its own right. As the Grateful Dead sang long ago, "one man gathers what another man spills." Most of the captured CO2 around the world is currently used for enhanced oil recovery, meaning it is pumped into older wells to push out the remaining crude.
But CO2 can be used in many chemical and industrial processes. "We are looking mostly at recycling, not sequestration," said Alain Goeppert, a research scientist at the Loker Hydrocarbon Research Institute at the University of Southern California, and co-author of Beyond Oil and Gas: The Methanol Economy. "We are chemists, so we want to do something with the CO2 we capture. That means recycling it into fuels and other materials, especially methanol."
Goeppert is primarily working on capturing CO2 from the air, not from flue gases, which he says have too many impurities. He concedes that current air capture technology is not efficient enough for large scale CO2 recycling, but says it has other advantages, including that it can be sited anywhere, not just at power plants, and that the materials used to absorb the CO2 last much longer. Moreover, he says that the concept has already been proved.
"A company in Iceland is already doing that: Carbon Recycling International," Goeppert said. "There, they are recycling CO2 with hydrogen they obtain from water. They use geothermal energy, which is relatively cheap. They have been producing methanol that way for five years, exporting it to Europe, to use as a fuel. It's still relatively small scale, but it's a start."
Automobiles can be converted to run on pure methanol for about $100. The alcohol can also be blended with ordinary gasoline (up to 15 percent) with no modification required, Goeppert says. "It even has a higher octane rating, so you can use a higher compression ratio and use less fuel for the same power."
"You can use it in diesel engines," he added. "There is a ship between Sweden and Germany, every day, running on methanol. It's much less polluting than diesel."
There are even ways to generate power that do not rely on fossil fuels and that consume CO2. Back during the Jimmy Carter administration, Christopher D. Barry, now chairman of the Ocean Renewable Energy technical and research panel of the Society of Naval Architects, began working on ocean thermal energy conversion. OTEC exploits the temperature difference between surface water and near-freezing water from the deep ocean to drive turbines producing electricity. The turbine and heat exchangers have to be very efficient – but even back in the 1970s, a test project generated a megawatt.
Here's the relevant part: OTEC can be carbon negative. "Ocean thermal energy brings up enormous amounts of cold water, which is laden with nutrients," Barry said. "If you bring nutrients up to the surface, you have big fisheries. Most of the tropical ocean has very little life. And where you have life, you have carbon pickup, and eventually you have sequestration. The creatures eat it," he said. "The ocean is a natural carbon sink; we just need to enhance it."
Barry has a number of biological schemes to capture carbon that should warm the hearts of environmentalists. Restoring the health of littoral waters, like Chesapeake Bay, would encourage the return of oysters and other shellfish. "A bushel of oysters is about 30 pounds of carbon dioxide, because it's mostly shell, and the shell is mostly calcium carbonate," he said. "I don't know how expensive it will be to restore littoral waters, but certainly less than pulling CO2 out of a flue and then pumping it hundreds of miles to bury it."
My personal favorite, however, is the restoration of the sea otter population. Giant kelp beds stretched from Japan to the West Coast until the decimation of the sea otter population for their furs allowed sea urchins to proliferate wildly. The sea urchins eat the kelp roots. "Kelp forests are carbon sinks themselves," Barry said. "Loss of the sea otter caused the loss of the Pacific coast kelp forests except in Monterey and parts of Alaska. One way to improve carbon sequestration is to restore sea otters."
Now, if only oysters and otters could generate electricity, too.
As a Practical Matter
The irony is that CCS technology is ready to go, right now, but may fall by the wayside for lack of political and popular support even when it is competitive with renewables. As Herzog of MIT notes, renewables have enjoyed a huge technology push from governments worldwide, including investment tax credits, production tax credits, feed-in tariffs and portfolio mandates. Similar programs for other low carbon technologies like CCS and nuclear power have been lacking.
"We have a renewables/efficiency policy," Herzog pointed out. "We don't have a climate policy. I personally feel you need a revenue-neutral carbon tax, and you need the markets to solve the problem."
Despite the fanfare that surrounded the Paris agreement, achieving even modest reductions in carbon emissions will be a stretch as China and India flex their industrial muscles. Limiting the warming of the planet to 2 degrees Celsius above the pre-industrial level remains far out of reach. Ending the era of fossil-fuel emissions and converting entirely to clean energy by the middle of this century is a grand ambition, but a more pragmatic portfolio approach seems prudent.
Carbon capture and storage "is based on our current technology, a necessary element of any deep decarbonization of our energy system and economies," said Oliver Sator, a research fellow at the Institute for Sustainable Development and International Relations in Paris. "There is a big gap between the technological potential, which is there for CCS, and where the policy positions are. We've been willing to throw an enormous amount of money to scale up renewables, though it was nowhere near cost-effective, but for CCS there's been nothing comparable, even though it seems essential," he said.
Sator sees a role for CCS in industrial processes that release CO2. "There are also a lot of non-energy emissions, where there are no obvious alternatives" to CCS, he said. "We're not going to stop using steel." But while rapid advances in renewables have reduced the role for CCS in energy, it still has a critical part to play. "The focus really needs to be on CCS as part of a broader portfolio."