Biomass

Traditionally, biomass has been used in four ways:

 1. For industrial purposes (shelter, building materials, furniture, utensils, etc)

 2. Burning (for domestic energy use such as heating, lighting and cooking, and for land clearance) 

 3. Conservation (left on land or added to soil as compost, to enrich soil and biodiversity, avoid erosion, etc.) 

 4. For food (including livestock feed, while using fertilizers and with waste dumped in landfills or sea)

In the light of rising costs of fossil fuel and climate change concerns, other uses are considered, specifically: 

 5. Low-footprint food (reduced meat and reduced use of chemical fertilizers, with waste processed)

 6. Commercial combustion in power plants, furnaces, kilns, ovens and internal combustion engines

 7. Burial 

 8. BECCS (Bio-Energy with Carbon Capture & Storage)

 9. Biochar (Pyrolysis resulting in biochar, syngas and bio-oils)

10. Biochar + BECCS (Biochar + Bio-Energy with Carbon Capture & Storage)

Table 1. Comparison of methods to process biomass (Energy and Carbon)

	Combustion	Burial	BECCS	Biochar	Biochar + BECCS
Energy - year 0	1.0	-0.1	0.8	0.5	0.5
Carbon - year 0	-0.1	1.0	0.8	0.5	0.9
Energy - out years				0.4	0.4
Carbon - out years				0.5	0.5
Total	0.9	0.9	1.6	1.9	2.3

Above table by Ron Larsen, from this message, shows five methods to process biomass, rated (with 1.0 being the highest score) for their ability to supply energy and for their ability to remove carbon from the atmosphere.  

Above table shows that each way to process biomass waste has advantages and disadvantages:

 6. Combustion may seem attractive for its supply of energy, while having negative impact due to emissions 

 7. Burial can minimize emissions, but it doesn't provide energy, in fact it costs energy

 8. BECCS can score high on immediate energy supply as well as on avoiding carbon emissions

 9. Biochar scores well regarding immediate energy supply and emissions, with additional future benefits

10. Biochar + BECCS has all the benefits of biochar, while also capturing and storing pyrolysis emissions

The table below also incorporates above-mentioned traditional use of biomass, while using a wider footprint, i.e. with scores not only reflecting the ability of the method to remove carbon from the atmosphere, but also looking at emissions other than carbon.

Table 2. Comparison of ten uses of biomass (Energy and Footprint)

	Energy - year 0	Footprint - year 0	Energy - out years	Footprint - out years	Total
Industrial	-0.1	0.1			0.0
Burning	1.0	-1.0			0.0
Conservation		-0.2			-0.2
Food		-0.3			-0.3
Low-footprint food					0.0
Combustion	1.0	-0.1			0.9
Burial	-0.1	1.0			0.9
BECCS	0.8	0.8			1.6
Biochar	0.5	0.5	0.4	0.5	1.9
Biochar +BECCS	0.5	0.9	0.4	0.5	2.3

Biochar gets its positive "out years" scores for increasing vegetation growth over time, as it improves soil's water and nutrients retention, while also reducing the need for chemical fertilizers. 

These qualities of biochar are also helpful in efforts to bring vegetation into the desert by means of desalinated water, as proposed by a number of scientists. A study by Leonard Ornstein, a cell biologist at the Mount Sinai School of Medicine, and climate modelers David Rind and Igor Aleinov of NASA's Goddard Institute for Space Studies, all based in New York City, concludes that it's worth while to do so.

They envision building desalination plants to pump seawater from oceans to inland desert areas using pumps, pipes, canals and aqueducts. The idea is that this would result in vegetation, with the tree cover also bringing more rain -- about 700 to 1200 millimeters per year -- and clouds, which would also help reflect sunlight back into space.

This would not only make these deserts more livable and productive, it would also cool areas, in some cases by up to 8°C .

Importantly, vegetation in the deserts could draw some 8 billion tons of carbon a year from the atmosphere -- nearly as much as people now emit by burning fossil fuels and forests. As forests matured, they could continue taking up this much carbon for decades.

The researchers estimate that building, running, and maintaining reverse-osmosis plants for desalination and the irrigation equipment will cost some $2 trillion per year.

Links
Forest a Desert, Cool the World - ScienceNow Daily News
Ornstein et al. 2009 in press - Goddard Institute for Space Studies
Animations of 10-year average precipitation anomalies - Goddard Institute for Space Studies
Irrigated afforestation of the Sahara and Australian Outback to end global warming - Springerlink
Sahara Forest Project
Green machine takes root in Jordan
Afforestation - bringing life into the desert - Sam Carana
Vortex Towers could vegetate deserts - Sam Carana
Biochar - Sam Carana

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. Additionally, 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. The 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. The 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.

Agrichar

Most households only use one or at most two different rubbish bins, one for recyclables (paper & packaging) and one for general waste. It makes a lot of sense to add a third type of rubbish bin, for biowaste, i.e. kitchen waste, soil and garden waste.

Many people already compost such biowaste in the garden, but all too often such biowaste disappears along with the general waste in the rubbish bin. As displayed on the picture below, analysis in Waikato, New Zealand, shows that about half of household waste can consist of kitchen waste, soil and garden waste. Such waste ends up on rubbish tips, where the decomposing process leads to greenhouse gases, such as methane. And all too often, farmers burn crop residues on the land, resulting in huge emissions of greenhouse gases.

All such biowaste could deliver affordable energy by using the slow burning process of pyrolysis to produce agrichar or bio-char, a form of charcoal that is totally black. Organic material, when burnt with air, will normally turn into white ash, while the carbon contained in the biowaste goes up into the air as carbon dioxide (CO2). In case of pyrolysis, by contrast, biowaste is heated up while starved of oxygen, resulting in this black form of charcoal.

This agrichar was at first glance regarded as a useless byproduct when producing hydrogen from biowaste, but it is increasingly recognized for its qualities as a soil supplement. Agrichar makes the soil better retain water and nutrients for plants, thus reducing losses of nutrients and reducing the CO2 that goes out of the soil, while enhancing soil productivity and making it store more carbon.

When biowaste is normally added to soil, the carbon contained in crop residue, mulch and compost is likely to stay there for only two or three years. By contrast, the more stable carbon in agrichar can stay in the soil for hundreds of years. Adding agrichar just once could be equivalent to composting the same weight every year for decades.

Agrichar appears to be the best way to bury carbon in topsoil, resulting in soil restoration and improved agriculture. Agrichar has the potential to remove substantial amounts of CO2 from the atmosphere, as it both buries carbon in the soil and gets more CO2 out of the atmosphere through better growth of vegetation. Agrichar restores soils and increases fertility. It results in plants taking more CO2 out of the atmosphere, which ends up in the soil and in the vegetation. Agrichar feeds new life in the soil and increases respiration, leading to improvements in soil structure, specifically its capacity to retain water and nutrients. Agrichar makes the soil structure more porous, with lots of surface area for water and nutrients to hold onto, so that both water and nutrients are better retained in the soil.

In conclusion, recycling biowaste in the above way is an excellent method to produce hydrogen (e.g. for cars) and to bury carbon in the soil and improve production of food. Agrichar is now produced for soil enrichment at a growing number of places. The top photo shows agrichar in pellet form from Eprida. Australian-based BEST Energies has built a demonstration pyrolysis plant with a capacity to process 300 kilograms of biowaste per hour. It accepts biowaste such as dry green waste, wood waste, rice hulls, cow and poultry manure or paper mill waste. The plant cooks the biomass without oxygen, producing syngas, a flammable mixture of carbon monoxide and hydrogen. The agrichar thus produced retains about half the carbon of the original biowaste (the other half was burned in the process of producing the syngas).

Also important is to compare different farming practices. Carbon is important for holding the soil together. Farmers now typically plough the soil to plant the seeds and add fertilizers. This ploughing causes oxygen to mix with the carbon in the soil, resulting in oxidation, which releases CO2 into the atmosphere. Ploughing leads to a looser soil structure, prone to erosion under the destructive impact of heavy rains, flooding, thunderstorms, wind and animal traffic. Given the more extreme weather that can be expected due to global warming, we should reconsider practices such as ploughing.

Furthermore, the huge monocultures of modern farming have become dependent on fertilizers and pesticides. The separation of farming and urban areas has in part become necessary due to the practice of spraying chemicals and pesticides. Instead, we should consider growing more food on smaller-scale farms, in gardens and greenhouses within areas currently designated for urban usage. Vegan-organic farming can increase bio-diversity; by carefully selecting complementary vegetation to grow close together, diseases and pests can be minimized while the nutritional value, taste and other qualities of the food can be increased.

An issue of growing concern is nitrous oxide (N2O), which is 310 times more potent than CO2 as a greenhouse gas when released in the atmosphere. Much release of N2O is related to the practices of ploughing and adding fertilizers to the soil. Microbes subsequently convert the nitrogen in these fertilisers into N2O. A recent study led by Nobel prize-winning chemist Paul Crutzen indicates that the current ways of growing and burning biofuel actually raise rather than lower greenhouse gas emissions. The study concludes that growing some of the most commonly used biofuel crops (rapeseed biodiesel and corn bioethanol) releases twice the amount of N2O, compared to what the International Panel on Climate Change (IPCC) estimates for farming. The findings follow a recent OECD report that concluded that growing biofuel crops threatens to cause food shortages and damage biodiversity, with only limted benefits in terms of global warming.

All this is no trivial matter. Soils contain more carbon than all vegetation and the atmosphere combined. Therefore, soil is the obvious place to look at when trying to solve problems associated with global warming. By changing agricultural practices, we can add carbon to the soil and can minimize release of greenhouse gases.

References:

- Soils offer new hope as carbon sink
http://www.dpi.nsw.gov.au/research/updates/issues/may-2007/soils-offer-new-hope/

- Surprise: less oxygen could be just the trick
http://tinyurl.com/ywalt4

- What we throw away
http://www.waikato.govt.nz/enviroinfo/waste/whatwethrowaway.htm

- The Carbon Farmers
http://www.abc.net.au/science/features/soilcarbon/

- Living Soil
http://www.championtrees.org/topsoil/

- BEST Pyrolysis, Inc.
http://www.bestenergies.com/companies/bestpyrolysis.html

- Eprida, Inc.
http://eprida.com/hydro/

- Biofuels could boost global warming, finds studyhttp://www.rsc.org/chemistryworld/News/2007/September/21090701.asp

- Biofuels: is the cure worse than the disease?
http://tinyurl.com/yq9t8o

Companies producing agrichar:
- terra preta at bioenergylists.org
http://terrapreta.bioenergylists.org/company