Showing posts with label air capture. Show all posts
Showing posts with label air capture. Show all posts

Monday, November 14, 2011

Combining Policy and Technology


Technologies to remove carbon dioxide from the atmosphere

The Virgin Earth Challenge is a prize of $25m for whoever can demonstrate to the judges' satisfaction a commercially viable design which results in the removal of anthropogenic, atmospheric greenhouse gases so as to contribute materially to the stability of Earth’s climate.

Among the 11 shortlisted organizations are:
Above three technologies (biochar, carbon air capture and enhanced weathering) have great potential to help out with carbon dioxide removal (CDR) from the atmosphere. To combat global warming, further technologies should be considered, such as in Solar Radiation Management (SRM) and Arctic Methane Management (AMM).

How effective each technology is in one area is an important consideration; importantly, each such technologies can also have effects in further areas.

Further areas

Global warming is only one out of multiple areas where action is required; an example of another area is the hole in the ozone layer over Antarctica; effective action has already been taken in this area, but the growing hole in the ozone layer over the Arctic shows that further action is necessary.

A safe operating space for humanity is a landmark 2009 study by Rockström et al. It identifies nine essential areas where sustainability is stressed to the limits, in three cases beyond its limits.


Areas and applicable technologies

The table below shows these nine areas on the left, while technologies that could be helpful in the respective area feature on the right.

As said, each of technologies may be able to help out in multiple areas. As an example, by reducing carbon dioxide levels in the atmosphere, biochar and carbon air capture can also indirectly reduce carbon dioxide in oceans and thus help out with ocean acidification. Enhanced weathering could additionally reduce carbon dioxide in the oceans directly, thus presenting itself even more prominently as a proposal to achieve sustainability in this area.

Similarly, algae bags located in the mouth of a river could help out in multiple areas. They could produce biofuel and thus help reduce aviation emissions, while in the process catching fertilizer runoff, thus reducing emissions of nitrous oxide (the largest ozone-depleting substance emitted through human activities in a 2009 NOAA study) and also reducing depletion of oxygen in oceans.

1. Climate ChangeCDR: biochar, carbon air capture, enhanced weathering, algae bags, EVs, renewable energy, clean cooking & heating, LEDs, etc.
SRM: surface and cloud brightening, release of aerosols
AMM: methane capture, oxygen release, river diversion, enhanced methane decomposition
2. Ocean acidificationenhanced weathering
3. Stratospheric ozone depletionoxygen release
4. Nitrogen & Phosphorus Cyclesalgae bags, biochar, enhanced weathering
5. Global freshwater usedesalination, biochar, enhanced weathering
6. Change in land usedesalination, biochar, enhanced weathering
7. Biodiversity lossdesalination, biochar, enhanced weathering
8. Atmospheric aerosol loadingbiochar, EVs, renewable energy, clean cooking & heating, LEDs, etc.
9. Chemical pollutionrecycling, waste management (separation)

Implementing the most effective policies

Policy support for such technologies is imperative. Just like some technologies can help out in several areas, some policies can cover multiple areas. As an example, a policy facilitating a shift to cleaner energy can both reduce greenhouse gases and aerosols such as soot and sulfur. Sulfur reflects sunlight back into space, so reducing sulfur emissions results in more global warming, but conversely global warming can be reduced by releasing sulfur over water at higher latitudes.

How many different policies would be needed to support such technologies? What are the best policy instruments to use?

Traditionally, government-funded subsidies and standards have been used to contain pollution, sometimes complemented with levies and refundable deposits; this can also work for chemical pollution. Standards have also proven to be effective in reducing the impact of CFCs on the ozone layer, while - as said - policies could at the same time also be effective in other areas, in this case reducing the impact of CFCs as greenhouse gases.

However, standards don't raise funding for support of such technologies, while taxpayer-funded subsidies make everyone pay for the pollution caused by some. Hybrid methods such as cap-and-trade and offsets are prone to corruption and fraud, which compromises their effectiveness. Local feebates are most effective in facilitating the necessary shifts in many areas.

Two sets of feebates

To facilitate the necessary shift away from fuel toward clean energy, local feebates are most effective. Fees on cargo and flights could fund carbon air capture, while fees on fuel could fund rebates on electricity produced in clean and safe ways. Fees could also be imposed on the engines, ovens, kilns, furnaces and stoves where fuel is burned, to fund rebates on clean alternatives, such as EV batteries and motors, solar cookers and electric appliances. Such feebates are pictured as yellow lines in the top half of the image below.

Support for biochar and olivine sand could be implemented through a second set of feebates, as pictured in the bottom half of the image below. Revenues from these feebates could also be used to support further technologies, as described in the paragraph below.

Further technologies should be considered for their effectiveness in specific areas, including:
  • release of oxygen to help combat methane in the Arctic and to help combat loss of stratospheric ozone
  • use of plastic sheets to capture methane
  • use of radio waves to enhance methane decomposition
  • diversion of water from rivers to avoid warm water flowing into the Arctic Ocean
  • release of aerosols over water at higher latitudes
  • surface & cloud brightening to reflect more sunlight back into space



Professor Schuiling proposes olivine rock grinding


Dutch Professor Olaf Schuiling has been working on rock grinding for many years. Remember the Virgin Earth Challenge, launched early 2007 with the promise to award $35 million to the best method to remove greenhouse gases? Schuiling said: Let's grind more rocks! Last thing Schuiling heard was that he was among the final ten contenders.
Schuiling's method is simple. Crush olivine rock to small pieces and it will bind with carbon dioxide. This process - called weathering - happens in nature but takes a long time. Crushing and grinding olivine rock will speed up the process and is therefore often called enhanced weathering. It works best in wet tropical countries, but can be done everywhere around the world.
Schuiling proposes to cover beaches, levees and railway tracks with the material, and proposes olivine to be added to building materials like pavement and concrete. It can also be added to soil and water. Adding olivine can fertilize the soil and improve its ability to retain water, and can work well in combination with biochar and other ways to increase organic carbon in the soil. When added to the sea, it can reduce acidification, and stimulate growth of diatoms and other forms of biomass in the sea.
This is a win-win solution, Schuiling says, as it helps grow more food, while combating global warming. To add another win, it can also produce drinking water that is healthier than rain water. Schuiling recommends cities to build olivine hills, to remove carbon dioxide from the air while filtering water.
There's is a video with more background, in Dutch with English subtitles. Also have a look at this poster.

Comments


What works best is implementation of feebates that put in place combinations of local financial incentives and disincentives, as illustrated by the image on the right.

Energy feebates, working in a parallel yet complimentary way, can clean up energy supply within a decade, while feebates as pictured above can continue to bring carbon dioxide levels in the atmosphere back to 280 ppm, as well as bring down carbon dioxide levels in the oceans.

Rock grinding should be part of a comprehensive policy that also includes replacing fuel with renewable energy and support for biochar. The latter is also discussed in the posts Biochar and The Biochar Economy.

As the above diagrams try to show, biochar and olivine sand can be combined in soil supplements, to help bring carbon dioxide levels in the atmosphere back to 280ppm. Rebates could be financed from fees on nitrogen fertilizers, livestock products and Portland cement.

Enhanced weathering is possible with other types of rock, but more easily done with olivine. The paper Olivine against climate change and ocean acidification includes the map below with the global distribution of dunite massifs. By removing their lateritic overburden, the underlying dunites (rocks that consists of > 90% olivine) can be mined. 

As the image on the right shows, there's no need for long distance transport. One dot often represents several dunites and olivine is available in abundance at many places across the globe.

The benefits are great and this looks like one of the most economic ways to bring down carbon dioxide levels. 

The energy can come from wind energy, which is clean, price-competitive and available in abundance in many places. Rock grinding, the transport and distribution can be largely automated, and take place predominantly at off-peak hours, while wind energy can be supplied very economically at off-peak hours.

Olivine sand can also be combined well with biochar, as soil supplement. Have a look at the post the Biochar Economy.




Further reading:
Feebates
Biomass
Carbon Air Capture and Algae Bags
Enhanced weathering
Oxygenating the Arctic
Ozone hole recovery
Enhanced methane decomposition
Desalination
Vortex towers could vegetate deserts
Carbon-negative building
LEDs: When will we see the light?
Thermal expansion of the Earth's crust necessitates geo-engineering
Towards a Sustainable Economy
The way back to 280 ppm

Monday, May 4, 2009

Funding of Carbon Air Capture

Air capture of carbon dioxide is an essential part of the blueprint to reduce carbon dioxide to acceptable levels. Fees on conventional jet fuel seem the most appropriate way to raise funding to help with the development of air capture technology. Why target jet fuel? In most other industries, there are ready alternatives to the use of fossil fuel. Electricity can be produced by wind turbines or by solar or geothermal facilities with little or no emissions of greenhouse gases. In the case of aviation, though, the best we can aim for, in the near future at least, is biofuel. Technically, there seem to be no problems in powering aircraft with biofuel. Back in Jan 7, 2009, a Continental Airlines commercial aircraft (a Boeing 737-800) was powered in part by algae oil, supplied by Sapphire Energy. The main hurdle appears to be that algae oil is not perceived as price-competitive with fossil fuel-based jet fuel. Air Capture FundingAdditionally, the aviation industry can offset emissions, e.g. by funding air capture of carbon dioxide. The carbon dioxide thus captured could be partly used to produce fuel, which could in turn be used by the aviation industry, as pictured on the left. The carbon dioxide could also be used to assist growth of biofuel, e.g. in greenhouses. Algae can grow 20 to 30 times faster than food crops. A CNN report, more than a year ago, mentions Vertigro's claim to be able to grow 100,000 gallons of algae oil per acre per year by growing algae in clear plastic bags suspended vertically in a greenhouse. Given the right temperature and sufficient supply of light, water and nutrients, algae seem able to supply an almost limitless amount of biofuel. The potential of algae has been known for decades. As another CNN report describes, the U.S. Department of Energy (DoE) had a program for nearly two decades, to study the potential of algae as a renewable fuel. The program was run by the DoE's National Renewable Energy Laboratory (NREL) and was terminated by 1996. At that time, a NREL report concluded that an area around the size of the U.S. state of Maryland could cultivate algae to produce enough biofuel to satisfy the entire transportation needs of the U.S. In conclusion, it would make sense to impose fees on conventional jet fuel and use the proceeds of those fees to fund air capture of carbon dioxide. Apart from growing algae in greenhouses, we should also consider growing them in bags. NASA scientists are proposing algae bags as a way to produce renewable energy that does not compete with agriculture for land or fresh water. It uses algae to produce biofuel from sewage, using nutrients from waste water that would otherwise be dumped and contribute to pollution and dead zones in the sea. algae yieldThe NASA article conservatively mentions that some types of algae can produce over 2,000 gallons of oil per acre per year. In fact, most of the oil we are now getting out of the ground comes from algae that lived millions of years ago. Algae still are the best source of oil we know. In the NASA proposal, there's no need for land, water, fertilizers and other nutrients. As the NASA article describes, the bags are made of inexpensive plastic. The infrastructure to pump sewage to the sea is already in place. Economically, the proposal looks sound, even before taking into account environmental benefits. Jonathan Trent, lead research scientist on the Spaceship Earth project at NASA Ames Research Center, Moffett Field, California, envisages large plastic bags floating on the ocean. The bags are filled with sewage on which the algae feed. The transparent bags collect sunlight that is used by the algae to produce oxygen by means of photosynthesis. The ocean water helps maintain the temperature inside the bags at acceptable levels, while the ocean's waves also keep the system mixed and active. algaeThe bags will be made of “forward-osmosis membranes”, i.e. semi-permeable membranes that allow fresh water to flow out into the ocean, while preventing salt from entering and diluting the fresh water inside the bag. Making the water run one way will retain the algae and nutrients inside the bags. Through osmosis, the bags will also absorb carbon dioxide from the air, while releasing oxygen. NASA is testing these membranes for recycling dirty water on future long-duration space missions. As the sewage is processed, the algae grow rich, fatty cells that are loaded with oil. The oil can be harvested and used, e.g., to power airplanes. In case a bag breaks, it won’t contaminate the local environment, i.e. leakage won't cause any worse pollution than when sewage is directly dumped into the ocean, as happens now. Exposed to salt, the fresh water algae will quickly die in the ocean. The bags are expected to last two years, and will be recycled afterwards. The plastic material may be used as plastic mulch, or possibly as a solid amendment in fields to retain moisture. A 2007 Bloomberg report estimated that the Gulf of Mexico's Dead Zone would reach more than half the size of Maryland that year and stretch into waters off Texas. The Dead Zone endangers a $2.6 billion-a-year fishing industry. The number of shrimp fishermen licensed in Louisiana has declined 40% since 2001. Meanwhile, U.S. farmers in the 2007 spring planted the most acreage with corn since 1944, due to demand for ethanol. As the report further describes, the Dead Zone is fueled by nitrogen and other nutrients pouring into the Gulf of Mexico, and corn in particular contributes to this as it uses more nitrogen-based fertilizer than crops such as soybeans. The Louisiana coast seems like a good place to start growing algae in bags floating in the sea, filled with sewage that would otherwise be dumped there. It does seem a much better way to produce biofuel than by subsidizing corn ethanol. According to zFacts.com, corn ethanol subsidies totaled $7.0 billion in 2006 for 4.9 billion gallons of ethanol. That's $1.45 per gallon of ethanol (or $2.21 per gallon of gas replaced). As zFacts.com explains, besides failing to help with greenhouse gases and having serious environmental problems, corn ethanol subsidies are very expensive, and the political backlash in the next few years, as production and subsidies double, will damage the effort to curb global warming. At UN climate talks in Bonn, the world's poorest nations proposed a levy of about $6 on every flight to help them adapt to climate change. Benito Müller, environment director of the Oxford Institute for Energy Studies and author of the proposal, said that air freight was deliberately not included. The levy could raise up to $10 billion per year and would increase the average price of an international long-haul fare by less than 1% for standard class passengers, but up to $62 for people traveling first class. In the light of those amounts, it doesn't seems unreasonable to expect that fees imposed on conventional jet fuel could raise billions per year. Proceeds could then be used to fund rebates on air capture of carbon dioxide, which could be pumped into the bags on location to enhance algae growth. Air capture devices could be powered by surplus energy from offshore wind turbines. With the help of such funding, the entire infrastructure could be set up quickly, helping the environment, creating job opportunities, making the US less dependent on oil imports, while leaving us with more land and water to grow food, resulting in lower food prices.

Blueprint of a Sustainable Economy