The view from Shanghai, ChinaA recent
New York Times article - “
China Leading Global Race to Make Clean Energy” by
Keith Bradsher - reminded me to write down some thoughts about industry progress in reducing carbon dioxide emissions—a road less traveled.
The
Times has finally discovered that the Chinese will dominate the clean energy world by using cheap labor, a huge and hungry domestic market, governmental uber-subsidies and hordes of trained technologists. By clean energy, the author means wind and solar, with hydro and new nukes thrown in for good measure though not really discussed. Ironically, a raft of other, recent articles make the same point, and although the brevity of their treatment makes them worth reading, it leaves one wondering how much of this (“The Chinese are coming, the Chinese are coming!!!”) is truth and how much hyperbole.
So what should we do as patriotic Americans? Fortunately, a young
Ms. Miley Cyrus is on the case, so we can all breath a little easier. Incidentally, her song
“…Wake up America. Tomorrow becomes a new day. And everything you do matters. Yeah, everything you do matters… Oh, it’s easy to look away, but it’s getting harder day by day…” was more popular in Europe than in the US.
We Have Already Lost the Race for Wind Turbines and Solar PanelsLet’s concede this point. It is now practically impossible for European or U.S. industry to catch up with the Chinese in building and installing equipment such as advanced wind turbines and piezoelectric solar cells. So we can expect that wind and solar equipment manufactured in China will be at least cost-competitive if not dominant. Our response should be to buy those components from China and install them wherever they make economic sense.
But even in China, these clean energy sources will not necessarily be economically competitive with other traditional energy sources. All of these innovations are necessary. But they do not preclude in any way the need to innovate in the conventional energy sector, which will still be around and important in the year 2030 and beyond.
Even if the Chinese win this race, so what?
This still leaves plenty of room for
new technological innovation in other areas. The question is:
where does it make sense for us to innovate?Here are some suggestions:
- radically better wind turbines or
solar cells-
storage of off-peak clean energy
- better long distance high voltage transmission of clean power
- new methods for CO2 capture and sequestration
- geo-engineering (see previous post on
Nathan Myhrvold’s Stratoshield and Salter Sink)
The Chinese are also beginning to lead the world at long distance, high voltage transmission as well. However, installation and maintenance is another ballgame. We could innovate in areas that are part of this ecosystem where we already have an established lead and huge expertise.
Let’s Not Ignore the Biggest Clean Energy ContributorThis brings me to the original purpose of this blog entry. We must not overlook the ways to do
Carbon Capture and Sequestration (or Storage), which we’ll abbreviate as
CCS. Conventional power generation stations, either those already in place or the newer generation of coal-and-gas-fueled thermal power stations being rapidly installed in China, India and elsewhere are between half and 80% of capacity in many places. The huge stock of
sunk costs in coal-and gas-burning thermal power units will not be replaced by the best Chinese wind and solar equipment. unless their carbon emissions cannot be economically reduced.
So
the biggest opportunity is to create clean, economical fixes to the world’s stock of existing electric stations.The owners of these coal facilities have the lowest variable power cost in many areas of the world. In areas like the Middle East, gas is provided at such low value that this is the least cost producer of power. So most big utilities would like to continue to operate these sunk costs.
Refitting existing plants with proven CCS technology, especially
ethanolamine absorption and desorption, is difficult at many existing plants; is capital intensive; uses from 15 to 30 per cent of the capacity of the power station to remove CO2 and other pollutants; and seems to add about 3 to 4 US cents per KWH ($30 to 40 per MWH) to costs of generation of power. A good, concise treatment of the technology and cost for this approach is in
Energy Procedia 1 (2009), 1289-1295.
Yet the mega-utilities seem to be
betting politically on this retrofitting plus transporting, pressurizing and injecting of relative clean CO2 streams to subsurface storage sites. Once again, many environmentalists don’t like this solution either (go figure!).
Of course, for a sizable fraction of coal/thermal power facilities, a shutdown will be preferred to refitting. Yet coal is forecasted to be so much cheaper than other primary energy sources that massive refitting is still seen by utilities as the best answer.
Enter Shale Gas—The New Kid in the BlockIn North America and soon elsewhere, new discoveries of
shale gas deposits will make natural gas competitive with coal for most new facilities equipped with CCS. This is because
gas generates about half as much CO2 and because gas-fired plants are cheaper to build than coal-fired ones. Existing wind and solar technology will not be competitive with shale gas using new CCS technologies.
China Needs Coal CCS, but Someone Must Lead in InnovatingDespite
news to the contrary, this is where the U.S. and Europe have an innovation window! There must be some way to climb off of the experience curve for this mature CCS technology and develop a better, even radical improvement which has its own, lower experience curve.
So here’s my nomination: instead of pure CCS, as currently envisioned, we need to develop
Crud-O2 (explained below) as our CCS.
Let me explain: in the conventional coal power scheme, the flue gases are sequentially treated to remove nitrogen oxides (NOx), fly ash and particulates (including some heavy metals), sulfur oxides (SOx) and then subjected to CO2 capture. The emitted flue gas contains nitrogen, water and tails of each pollutant. Each processing stage adds costs for chemical and energy and subtracts net, available energy from the plant. Each pollutant needs separate handling and disposal and creates additional environmental exposure. NIMBY (Not In My Backyard) always rears its ugly head. So instead of doing this sequentially in a multi-stage, muti-handled operation, we need to develop means of recovering these streams as essentially one liquid stream, rich in CO2 but containing solids, metals, SOx, NOx, and perhaps some water: let’s call it
Crud-O2.
This recovery is similar to proposed schemes, where relatively clean CO2 having been
absorped and
desorped in an amine plant, must be compressed to a liquid for transportation. We propose that the entire flue gas stream, probably with solids filtered out, be compressed in multiple stages with intercooling, probably taking 4 or 5 stages. All components heavier than CO2 will condense, some in the intercooling step, some at the end of the train.
As an alternative design, refrigeration loops can lower the temperature of the
Crud-O2 until it forms a liquid at lower system pressure. Optimizing the use of compression or refrigeration, including the draining of liquids from the intercooling steps, is a design process very familiar to chemical and power plant engineers. As an end result, our
Crud-O2 storage vessel will contain all (or most) of our bad actors. Energy still contained in the flue gas, resembling the existing flue gases from a coal-fired plant with amine-CCS added, can be recovered back into the system, reducing net energy consumption.
With Oxygen Combustion, Crud-O2 May Be Even BetterThere is much R&D being done on replacing combustion air with oxygen, either partially (let’s call it enrichment) or completely. Current materials of construction will not withstand the temperatures generated with pure oxygen combustion, so designs use a recycle of cooled flue gases into the combustion chamber to limit the maximum temperatures. This approach makes a flue gas with progressive reduction of nitrogen content, hence more easily captured by compression/refrigeration into
Crud-O2. At the limit, it approaches zero flue discharge. Obviously, the energy for producing oxygen from air must be netted out of the net energy production, and the capital for an air separation plant must be added to the capital costs of such a scheme. Optimization is required, but the net result is the same, with all of the bad actors in our
Crud-O2 and ready for transport.
Crud-O2 Spends Eternity Under the SeaBut where in blazes do we take this
Crud-O2? Here, we enter Wonderland. As proposed for pure CO2 over several years by many creative types, we propose putting the
Crude-O2 in some appropriate place on the bottom of the ocean.
Depending on the properties of the
Crud-O2 and the temperature at the bottom of the ocean, it requires over 1000 meters of ocean depth, and some sources (
here and
here) suggest 3,500 meters of ocean depth. It’s easy to find out and scout unlimited places which fit, all over the world. The ocean has many square miles of such places.
Shades of Captain Nemo At this depth, there is virtually no solar radiation, the population is mostly primitive worms, the bottom is covered with debris and plant/animal material which drifted down over the millennia, currents are rare or slow, and (importantly) CO2 or
Crud-O2 are denser than the water overhead. A quiescent layer of CO2 on that bottom would slowly diffuse into the water above at the interface, which environmentalists do not like. We don’t see why they don’t like it, since the oceans of the world already contain gajillions of tons of CO2. Better the deep oceans than our lungs? But there is an easy answer to how to keep the
Crud-O2 components from leaving this dark, underwater tomb.
We suggest that a membrane made of fibers, coated with polymeric material to be relatively impermeable and permanent, be installed at the bottom of said ocean before
Crud-O2 is injected beneath the membrane. Hydrodynamics virtually guarantees that the membrane, as it slowly rises atop the lake of
Crud-O2, is under very minor net forces. The membrane prevents diffusion of
Crud-O2 components up into the water (and the obverse, of course). but since they are acting on both top and bottom of the membrane, they cancel each other out. We envision rolls of coated fabric, with Velcro or other connectors at all margins, dispensed and connected by remote vehicles. A trench would be an ideal location, so that as the reservoir is filled, the membrane rises at the virtually flat water/
Crud-O2 interface.
Using a protective membrane at such depths suggest several advantages to a good design engineer. Polymer science knows how to design the membrane for a lifetime of centuries, given the cold, dark, quiescence in ocean trenches. Resisting any corrosive effects of the
Crud-O2 components is relatively easy for a polymer chemist, but the lack of light, temperature or cathodic currents makes this an ideal environment for long life. Also, the
Crud-O2 can be delivered down to the bottom with minimal pumping pressure, enough to overcome flow pressure drop, as the head in a standpipe will be approximately the same as or slightly larger than the head in the surrounding water. The same consideration means that a standpipe from the surface down to the membrane can be light gauge pipe, as internal pressures and external pressures are virtually identical. Hydraulics also makes a “blowout” very unlikely and of minimal impact. A “blowdown” would be much more likely.
In each of these cases, contrast the situation with high pressure pumping into depleted oil or gas formations, where high pump costs and high energy usage are the norm. Blowouts are possible. Safety is problematical. With
Crud-O2, you need only liquefy the stream and more energy use is not major. This is an elegant solution.
And in the worst case, someone in the year 2050 or 2150 or 3010 can easily fix any unforeseen developments.
Transporting Crud-O2We envision towable, multiwall pressure vessels coated on the inside to resist
Crud-O2 components. Think giant kielbasa with double casing, having buoyancy and stiffness between the two walls.
Crud-O2 can be shipped either at high pressure at ambient temperatures; insulated/refrigerated to low temperature and modest pressure; or somewhere in between. Unloading would not require any change of conditions to all injection to the bottom. These tanks can be rolled into a stream or river near the source; towed by virtually any tow boat to join more tanks; be towed as a “train” out to sea; stationed by a platform above the storage site; unloaded by low head pumps in good weather only; sent back with a “heel” of
Crud-O2 or else inflated with nitrogen (say); and eventually show up at some other
Crud-O2 source for refilling. Repeat over and over.
Of course, we could design to deliver the
Crud-O2 by pipeline in those cases where this is preferable. A subsea pipeline could be made of flexible material and would be almost neutrally buoyant, since liquid CO2 and water are close in density.
Bonus Clean-up Opportunity: Bunker FuelOnce the elements of the
Crud-O2 system are in place, we would find other uses beyond stationary power stations and industrial plant furnaces. The
International Maritime Organization (IMO) of the UN is trying to reach final rules governing the quality of
bunker fuel used by the great majority of the world’s largest ships. Closer to home, the
Environmental Protection Agency is
targeting an 80% cut in nitrogen oxide, or NOx, emissions by 2016.
Beach Beautification with Bunker Fuel Bunker fuel is literally the bottom of the barrel in the world’s refineries, blessed with several percent sulfur and scads of heavy metals. Only petroleum coke is somewhat heavier (a solid) and bunker fuel has roughly the same consistency as road asphalt. The proposed IMO rules will limit the allowable sulfur in bunker fuel from the current levels of 3.5% to 0.5% by 2025. Oil refiners are skeptical about whether they can meet this new spec at any reasonable cost, which begs the question, since bunker is used only because it is cheap. Really cheap, compared to any alternative liquid fuel.
We envision multistage compression on the ships, with seawater heat exchangers, to create
Crud-O2 from the stack gases. Multi-wall, cylindrical tanks would be ideal repositories, as these could be stowed with freedom anywhere on these large ships. When near a port or a
Crud-O2 repository, the ship could let the tank overboard … it could even be towed … for pickup by a sea train of CO2. Thus equipped, the ship would be able to burn whatever bunker was available with pollution of the air as is occurring today.
There are approximately 50,000 ships over 5,000 DWTons which rely on bunker fuel. The largest bunker burners - the largest container ships - burn 75 to 125 tons/day of bunker fuel when under way. Even larger tankers and bulk carriers actually burn less as they move at slower speeds. But at 2.5 T/day of CO2/Bunker, and assuming only 50 T/day for 50,000 ships sailing 250 days per year each, the
annual CO2 load is over 1.5 billion tons. And this CO2 recovery would happen all over the world. In the case of bunker fuel, the recovery of the sulfur is the driving force, not CO2 reduction.
Even under IMO’s proposed regulations, these ships would still be allowed to emit CO2 without limit, and be carbon taxed. There are probably 400 significant oil refineries in the world which produce bunker. These will be required to invest to improve their bunker fuel and produce less of it, given the proposed IMO regulations.
The scope of this is enormous.
What we need to compete with the Chinese, is not so much incentive, but
imagination. Our existing industrial solutions won’t cut it. We can and must innovate our way out, or learn to live with the smog, the pollution, the global warming, and the
global insecurity it produces.
NEXT: More fun clean-up applications for Crud-O2! You betcha.