A Simple Plan

As wind and other renewables get cheaper, intermittency will matter more.

I have an idea that I've alluded to here before and which I've been trying to explain on Twitter but which requires -- a bit -- more than 140 characters to explain.

Here it is in a nutshell: fossil fuels could make great grid-scale batteries.

The problem is this: many clean energy sources are either intermittent (solar, wind) or have the opposite problem, being "fixed" (difficult to adjust to demand) like nuclear or geothermal. This is in contrast to, say, a modern natural gas plant, which can easily adjust its output minute by minute to match the demand.

Conventional batteries continue to get better and cheaper, but right now their capacity is orders of magnitude below what would be needed to store, say two or three weeks of energy.

However we do have a large amount of energy storage in the form of fossil fuels: liquid, solid, and gas. This form of storage is stable on geological time scales and extremely energy dense. Unlike many of the alternatives, including chemical batteries, capicators, pumped hydro storage, or molten sodium, the infrastructure to store and release hydrocarbon energy is simple and cheap -- in the case of petroleum, it can be as simple as a barrel or a hole in the ground.

The storage capacity of the German natural gas network is more than 200,000 GW·h which is enough for several months of energy requirement. By comparison, the capacity of all German pumped storage power plants amounts to only about 40 GW·h (Wikipedia). 

These are some of the reasons, of course, why fossil fuels have dominated our energy mix for so long (especially in the transport sector) and threaten to do so for many decades to come. But in using synthetic fossil fuels intended to store power, rather than provide power, we might be able to sidestep the disadvantages of these fuels, whilst retaining some of the crucial benefits.

Start with a conventional gas plant equipped with carbon capture technology (assuming we ever get serious about perfecting and deploying that technology.) Then, rather than put the CO2 in the ground, feed it into a synthetic natural gas plant and use a clean energy source to turn the CO2 back into gas. Burn, capture, and un-burn as needed in a closed cycle that doesn't release CO2 into the atmosphere.

Such a program assumes an abundance of clean energy [1], since carbon capture and synthesizing natural gas both require large amounts of energy relative to the energy stored in the final product. It can easily accommodate intermittancy as well as fixed or semi-fixed outputs. Since you can package and ship fossil fuels, this also means that the generation capacity can exist far from where the power is needed.

Another advantage is that this repurposes infrastructure we already have. We already use natural gas plants to adjust output to demand. We already have literally hundreds of billions of dollars of global infrastructure dedicated to the storage, transport, and burning of fossil fuels. Using hydrocarbons this way would simply mean that we stop pulling them out of the ground and recycle the emissions back into fuel. Much of the same infrastructure could be used.

I still think you would want a smart grid, dynamic pricing of electricity, HVDC networks, and some battery (or battery-like) grid-scale storage. These might function well enough that you wouldn't need this work-around on a regular basis. But it would be available to you if, say, there was a prolonged period of low solar output, or low wind output, or if a nuclear disaster led the government to shut down some or all of the nation's nuclear reactors.

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1. If we estimate that capturing the CO2 require 30% of the energy of burning the gas, and turning CO2 back into gas requires 120% of that energy, you'd need about 1.5MWh of clean energy for every MWh of emissions-free syngas.

Reforestation as carbon sequestration

Source.

In my previous post, I suggested that geoengineering might not have to persist continuously for thousands of years, if solar radiation management were used, not as a "destination therapy" but as a bridge, in combination with intensive mitigation, until a realistically slow program of carbon sequestration could take effect. How the carbon might be sequestered wasn't discussed. Chris Reynolds offered offers some options (from the relevant Wikipedia page):

Creating biochar (anaerobic charcoal) and burying it to create terra preta

Bio-energy with carbon capture and storage to remove carbon and simultaneously provide energy

Carbon air capture to remove carbon dioxide from ambient air

Ocean nourishment including iron fertilisation of the oceans

All of which have land use or energy input requirements. Clearing more land would place more pressure upon ecosystems, or food prices. Any energy used would have to be non fossil fuel, which would eat into whatever offsets could be made to fossil fuel burning reductions. Overall the whole process would have to not impact the poor (food prices), and would have to be substantial.

Obviously a tall order. But is there perhaps a way around some of these requirements, a way to sequester carbon without clearing more land, putting more pressure on ecosystems, or investing a lot of (our own) energy? It turns out there is!

Simple reforestation could sequester 3Gt/year of CO2. In fact, simply halting deforestation (18% of current emissions * 33Gt = about 6Gt of CO2 per year) would more than do the trick. But since we are eventually going to have to push our emissions near net zero anyway, the gain from halting deforestation is already "baked in" to the mitigation scenario (which was to leave us with 1,200Gt in net emissions including carbon-cycle feedbacks.) But what is not baked in is adding back forest cover.

Obviously this would be a slow and difficult process. It would involve increasing housing density, abandoning uneconomic farms and ranches (a disastrous hobby of rich governments the world over; the price tag for agricultural subsidies in 2011: $252 billion)) and growing food more efficiently on the land that remains. It might mean more expensive meat, tilting our diets towards more grains and pulses. But the potential gains are substantial. In fact, they are sufficient:

"The woody biomass of forests is estimated in
this paper to contain 300 × 10^9 tons carbon. For
comparison, the cumulative emissions from the
combustion of fossil fuels in the 19th and 20th
century were about 280 × 109 tons. In 2000, the
atmosphere contained about 790 × 109 tons in
CO2 (Enting et al. 2001, Marland et al. 2002)."

-- "New, Low Estimate for Carbon Stock in Global Forest Vegetation Based on Inventory Data"

About 30% of the world's forest cover has been lost in the last two centuries, since the Industrial Revolution. Taking the conservative estimate of the forest biomass quoted above, restoring the world's forests to their extent a few centuries ago could trap at least 126Gt of carbon, which is the equivalent of about 462Gt of CO2 -- a hair more than I said we needed to get back to a reasonable atmospheric CO2 level and stop solar radiation management.

I'm not sure why reforestation didn't make Chris' list, above. It does have a prominent place on the wikipedia page for carbon sequestration, but not for carbon dioxide removal. Just speculating, I think one might overlook the obvious potential of reforestation because it so obviously is very slow, and would be completely unable to cope with the BAU emissions expected in the 21st century. Once again, there is a critical difference between looking at geoengineering as cure (hopeless and stupid) and looking at it as one element of an intensive program to keep the world under 2C, with its specific role being to buy a little time.

Does geoengineering have to continue for thousands of years?

Cloud whitening, one geoengineering strategy

Chris Reynolds at Dosbat expresses the basic pro-science critique of geoengineering:

With the seriousness of the situation regards AGW becoming more clear, talk of geo-engineering has increased. I think that rather than try to stem population increase, examine our economic system and expectations, and reduce CO2 emissions, this will be seen as a viable option in the years to come.

However geo-engineering will, I am confident, be used as an excuse to carry on emitting CO2 and avoiding dealing with the fundamental flaw in our civilisation; exponential growth in a finite world. It is dangerous and is a recipe for disaster.

He may be absolutely correct on all points; the only parts I take issue with are the bolded ones (and the finite growth thing, a bit.)

The first point, the "rather than," is one we have to confront on a regular basis with the adapt-nik ("Don't mitigate -- adapt!) subspecies of lukewarmer. To wit: we can (and must) do more than one thing at a time. The resources required to investigate and prepare for the possibility that we may need to geoengineer are miniscule relative to mitigation, adaptation, or even population control.

If we were only going to do one thing, it sure as hell wouldn't be geoengineering. But we're going to have to do more than one thing.

The second point, that geoengineering may be used as an excuse to defer action, is a serious concern. Geoengineering would only work as a temporary bridge to allow intensive mitigation to bear fruit. But would it, actually, become an excuse for inaction?

This is a different, and slightly more upbeat, counterargument compared to the related riposte: "We don't need an excuse for inaction; we're excusing it fine as it is." In that fatalistic outlook, geoengineering becomes like a clean needle program for heroin addicts: we wish we could fix the underlying issue; we can't; we're going for damage control.

I am not such a fatalist; and I do not necessarily think that the availability of geoengineering will make mitigation less attractive. Consider, for example, how the adapt-vs-mitigate debate has unfolded (or failed to unfold) after Hurricane Sandy. Experts looking at the flood surge have suggested we could have prevented a large portion of the roughly $50 billion damages using $10-$15 billion dollars in floodgates. So my question is: Where are the adaptniks screaming for these new defenses?

I was able to find a tepid endorsement from Bjorn Lomborg which radically lowballed the cost of said adaptation.

Much of the risk could be managed by erecting seawalls, building storm doors for the Subway, and simple fixes like porous pavements – all at a cost of around $100 million a year.

If you follow the link, it leads to an article from Popular Science which includes this:

If New York—part of the Northeast megaregion—suffers a direct hit, workers will spend weeks pumping a billion gallons of brackish water out of its subway and train tunnels. The salt will corrode power lines, transformers and thousands of brakes and switches that control the trains. Some subsystems could take a year or more to restore.

To avoid such a scenario, New York state recommends the city invest well over $100 million a year in storm protections. City planners are already experimenting with dozens of low-tech fixes, says Adam Freed, deputy director of the Mayor's Office of Long-Term Planning and Sustainability.

 Note "well over $100 million" not "around $100 million." And while the original source describes these "dozens of low-tech fixes" as merely able to mitigate the nightmare scenario, in Lomborg's retelling they eliminate "much of the risk."

Lomborg also repeats the fallacy that the risks of a damage storm surge have nothing to do with climate change -- even though sea level rise, by definition, makes storm surges more destructive.

And that tepid, dishonest, weasel-worthy endorsement was really about all we heard from the "adapt, don't mitigate" crowd after Sandy. Judith Curry had a guest poster make the pitch for more weather satellites. Lucia Liljegren, not a word. So why not pitch adaptation in this brave new world?

My theory is, actual real-world adaptation makes the problem of global warming too real. It's one thing when "adaption" is an abstract concept describing something we may do in the future. But when it actually comes down to spending tens of billions of dollars on flood defenses, planned retreat from parts of the coastline, restoring wetlands, lowering levees, hardening the power grid, and beefing up the first responder network -- well, if you start spending that kind of money (hundreds of billions for starters, talking about the US alone), people might get to wondering why this global warming stuff is so gosh darned expensive and getting more so. And that might lead them to ask when we are going to stop adding to the bill by spewing billions of tons of CO2 into the air.

Geoengineering might similarly offer the public some clarity on this issue. I assume it will be far more expensive that it currently seems, it will be highly controversial on the world stage, it will have unwanted side effects and limited efficacy. Researching and preparing such a system might have the opposite of the effect Chris expects; it might focus the public's mind on what a god-awful problem this is and how we need to get busy fixing it.

If we research and prepare this tool (not deploying it until/unless we win an international consensus and after warming has crossed a specific threshold or we see evidence of rapid catastrophic feedbacks) the debate which ensues may, as Sandy has, stimulate the public and international debate on mitigation, so as to prevent or minimize the use of such desperate measures.

Another major concern with geoengineering schemes is the impracticality of keeping them running for a long, long time:

Why do I say we would need to keep up SRM for millennia?

Archer & Brovkin's 2006 paper "The Millennial Atmospheric Lifetime of Anthropogenic CO2", PDF, shows that the emissions of CO2 will remain in the atmosphere/ocean system for thousands of years. Their abstract sums up their findings perfectly:

The notion is pervasive in the climate science community and in the public at large that the climate impacts of fossil fuel CO2 release will only persist for a few centuries. This conclusion has no basis in theory or models of the atmosphere/ocean carbon cycle, which we review here. The largest fraction of the CO2 recovery will take place on time scales of centuries, as CO2 invades the ocean, but a significant fraction of the fossil fuel CO2, ranging in published models in the literature from 20–60%, remains airborne for a thousand years or longer. Ultimate recovery takes place on time scales of hundreds of thousands of years, a geologic longevity typically associated in public perceptions with nuclear waste.

So if we take any geo-engineering scheme that doesn't involve massive emissions reductions or active draw-down of CO2, we need to keep it up for at least 1000 years, the more CO2 we emit the longer the recovery of CO2 back to pre-industrial will take.

And if we falter...

That's obviously a legitimate concern. There isn't a single government on the face of the Earth that has maintained its present form of government for even a single millennium. If we are expecting them to maintain a stable geoengineering scheme for thousands of years, that's obviously impractical. And since solar radiation management strategies mostly poop out within a few years of stopping, you confront the possibility of decades or centuries of global warming hammering the world in the space of a few years.

Brrrrrrrrrr. I've scared myself. But perhaps the picture is not so dire. What if we look at geoengineering not as a mono-strategy, but, as I suggest, as one component of a threefold strategy of adaptation, mitigation, and geoengineering?

Let's say we get serious about mitigation and end up with 1,200Gt of CO2 equivalent added to the atmosphere (either it took too long to forge agreement, or the cuts could not be made fast enough, or the carbon feedbacks hit us too hard; we missed the 1,000Gt goal for 2C, but only just.) About 60% of that shows up in the atmosphere; the rest is immediately taken up by the carbon cycle. 720Gt. That's us, permafrost melting, forest dieback, what have you.

Let's say 50% of that remains in the atmosphere 300 years later. That's 360Gt. Meanwhile we are practicing some solar radiation management with cloud whitening and contrails and aerosols injected into the stratosphere. But we also have been doing some carbon sequestration.

Carbon sequestration is hard: suppose we don't get it off the ground for 20 years and it then takes us 30 years to ramp up sequestration to a grand total of 3Gt/year (that's about 9% of current emissions). We then practice that for about 150 years. That would take out 450Gt, but some of that would have been sequestered anyway -- we will only count 2/3 of the 450Gt as actual sequestration -- 300Gt. 

That leaves us with 60Gt above preindustrial -- about 330ppm of CO2 -- and we can probably stop spewing stuff into the sky at that point, the 200-year mark. Two hundred years is a very long time, but it is a lot less than thousands of years. Many governments have been more or less stable for 200 years, including the United States.

The exact figures are subject to debate, but the basic thrust is clear: two ideas that seem impractical on their own (solar resource management and carbon sequestration) get much more reasonable if you intelligently combine them with each other and intensive mitigation. Without mitigation, none of this works: you're continuing to shoot holes in the bottom of the boat as you're bailing it out.

Let me count the ways

How can we as a society slow climate change?

Right now the discourse about solutions is limited by the problem that many of the stakeholders have refused to come to the table, instead denying the problem exists, or prioritizing other concerns.

Someone like me, designing a program more or less in a vacuum, is free to come up with what they view as a simple and an optimal approach. But when the action really starts, the program will likely not be optimal, and not be simple. That's OK: slowing climate change is a matter of survival, and like fighting a war, we do not need to find the optimal solution, just a solution that works.

It's easy to lose sight of that, I think. Creating a low-emissions society is likely to be an expensive and difficult undertaking, and when arguing for our own favorite approach, it is easy to slip into the mentality that says if this is not done in the best way (my way) that failure is assured.

+80m sea level -- not soon, but soon to be inevitable

If we embark on a messy, complicated, in some measures unrealistic approach; an approach that pampers some stakeholders and imposes an unfair burden on others, that will be inefficient, and in some measure unjust, but nowhere near as bad as doing nothing.


Progressives, environmentalists, conservatives, and libertarians are likely to have different opinions as to the best approach. We should celebrate the day when everyone is arguing about how to fight climate change, rather than arguing about whether it is happening. The wider the array of options, the more likely any given faction can find an approach they like. So what are some of the options?

From Nordhaus et al (2010)

Carbon taxes (higher or lower), cap and trade (fixed allowances versus falling quotas vs buy-back), regulation (industries must cut emissions by 5% per year, figuring out how themselves; energy efficient technologies mandated; high mileage standards for cars), direct intervention (by, for example, mass producing the new AP1000 reactor like Liberty ships, by the thousands. Or, for the more ambitious, we could quickly finalize and mass produce something such as a thorium-based molten salt reactor.) There is carbon sequestration, via tree planting or no-till agriculture or subterranean injection or transferring the carbon to the deep sea.

There are various methods of geoengineering: aerosol injection, painting roofs white, shooting a saltwater spray upwards to generate more reflective clouds.

We can subsidize research and development into low-carbon energy sources; we can undertake a variety of methods to improve energy efficiency (upgrading to a national HVDC grid, for example, or changing building regulations, or reducing traffic congestion with smart highways, or improving our rail networks.)

In terms of reaching an international accord, we can proceed with multilateral negotiations, like the ones that produced the Kyoto Protocol, or we could pursue a more muscular approach, like the recent EU ruling on commercial airline emissions; identify large countries ready to move forward and pressure others to cooperate with trade carrots and sticks.

I could go on. Some of these methods are better than the others; most would not work singly, meaning we need some combination of approaches. Geoengineering, for example, is not (in my opinion) practical by itself, chiefly because you would have to continue it for hundreds or thousands of years, and any interruption, such as an international conflict, could lead to extremely rapid warming. We might, however, decide to gradually reduce our emissions over the next century, using geoengineering for a couple of centuries to avoid tipping points, and ramping up carbon sequestration to have CO2 back at a reasonable level by then.

We have to do something, and soon. The harmful effects of global warming continue to arrive ahead of schedule (h/t Steve Bloom.)

Real green jobs: 4 more key projects

 I've written here about why conventional "green jobs" are a problematic concept. When the government tries to cultivate a given industry to create jobs, there are many potential stumbling blocks. The industries may not be labor-intensive. The government may back the wrong industries or the wrong technologies. The parts that are labor intensive may move overseas. They may require extensive training, and when the work is completed, that training may be useless.

Over here, I suggested a few nontraditional paths to green jobs:

1. We could upgrade the nation's rail infrastructure with electrified rail replacing diesel engines and with the addition of double-track lines to minimize traffic congestion that can slow trains to an average of 2mph on some routes.
2. We could weatherize every home in America.
3. We could fully fund fuels management on all federal lands:
4. We could construct a backbone of HVDC lines.
 
These measures address the problems with traditional "green jobs" plans by striving for the following:


1. They focus on national infrastructure, a traditional "public good," rather than seeking to identify and promote particular companies or industries.
2. In themselves (without assuming a cascading effect of private-sector adoption) they significantly mitigate our national contribution to global warming.
3. They involve significant amounts of unskilled or semi-skilled labor (cutting brush, laying rail, weatherizing homes).
4. Much of the work generated necessarily comes from workers in the United States.
5. They are large, nationwide projects (large enough to stimulate employment, large enough to make a real difference to the climate.)

With those principles in mind, here are four other key projects with the potential to create real green jobs:


1. Rapid transit for the hundred largest cities in America. Subways and elevated rails work. Annual ridership of the New York subway is 1.6 billion. Most of the ten largest cities in America have them. Radically expanding electrified mass transit not only gets people out of their cars, it gets people too poor to afford cars mobility to get out to work (or their doctor's appointments, or to care care, or to do their shopping).

2. Paint all roofs white. Part of the problem with traditional approaches to creating "green jobs" is that jobs like working in a solar factory or erecting offshore windmills are highly skilled. Not very many people are qualified to perform them, and those that are are likely already employed. Meanwhile, while every sector of our economy has an unemployment problem, the worst problem is among those with a high school education or less:

So a green jobs plan with teeth should provide jobs to people at the bottom of the educational ladder -- which will also provide a greater dollar-for-dollar stimulus. So how about painting roofs white?

AGWObserver highlighted exciting recent research on "negative radiative forcing":

The radiative forcing benefits of “cool roof” construction in California: quantifying the climate impacts of building albedo modification – VanCuren (2011) “Exploiting surface albedo change has been proposed as a form of geoengineering to reduce the heating effect of anthropogenic increases in greenhouse gases (GHGs). Recent modeling experiments have projected significant negative radiative forcing from large-scale implementation of albedo reduction technologies (“cool” roofs and pavements). This paper complements such model studies with measurement-based calculations of the direct radiation balance impacts of replacement of conventional roofing with “cool” roof materials in California. This analysis uses, as a case study, the required changes to commercial buildings embodied in California’s building energy efficiency regulations, representing a total of 4300 ha of roof area distributed over 16 climate zones. The estimated statewide mean radiative forcing per 0.01 increase in albedo (here labeled RF01) is −1.38 W/m². The resulting unit-roof-area mean annual radiative forcing impact of this regulation is −44.2 W/m². This forcing is computed to counteract the positive radiative forcing of ambient atmospheric CO₂ at a rate of about 41 kg for each square meter of roof. Aggregated over the 4300 ha of cool roof estimated built in the first decade after adoption of the State regulation, this is comparable to removing about 1.76 million metric tons (MMT) of CO₂ from the atmosphere. The point radiation data used in this study also provide perspective on the spatial variability of cool roof radiative forcing in California, with individual climate zone effectiveness ranging from −37 to −59 W/m² of roof. These “bottom-up” calculations validate the estimates reported for published “top down” modeling, highlight the large spatial diversity of the effects of albedo change within even a limited geographical area, and offer a potential methodology for regulatory agencies to account for the climate effects of “cool” roofing in addition to its well-known energy efficiency benefits.” Richard VanCuren, Climatic Change, DOI: 10.1007/s10584-011-0250-2.

 If a single square meter of roof counteracts 41kg of CO2, then painting 50 square meters of roof is the equivalent (in warming terms) of removing one ton of CO2 from the atmosphere. Depending on what kind of a carbon price you favor, this could be worth $50-$300. And you don't need a lot of education to slap on white paint.

3. Upgrade interstate highways with an automated highway system. There are roughly 50,000 miles of interstate highway (accounting for a third of all road travel) -- upgrading them would be a massive project that would be undertaken in stages. It would be expensive, but the payoff would be huge (not unlikely building the roads in the first place). Intelligent highways would move people faster, with greater fuel efficiency and fewer accidents.

The systems that have been road-tested (so to speak) rely on sensors planted meter-by-meter in the highway. This would be labor-intensive, but doubly rewarding; trips on intelligent highways would burn far less gas, and would be far less likely to get bogged down in traffic, where 4.8 billion hours a year are wasted. For knowledge workers, self-driving cars would also make driving time more productive -- makeup will be applied more evenly; kids can be yelled at more effectively! -- without the risk that the distractions will lead to lethal accidents.

4. Implement no-till agriculture in American fields. No-till agriculture in appropriate soils and with appropriate crops has been found to sequester carbon, reduce NO2 emissions, reduce soil erosion, and conserve water, all at a reasonable cost. To encourage this, we can provide carbon sequestration credits, free training in no-till methods.

This promotes employment in custom weeding, herbicide application, as well as sequestering carbon. Less fuel is burned when tilling is omitted.

Substituting employment costs (jobs) for diesel fuel costs -- and sequester carbon in the process. Sounds like a green job to me.