Monday, April 30, 2012

Vortex towers could vegetate deserts

Plans to bring water and vegetation to deserts through vortex towers and biochar

Vortex towers are typically seen as ways to produce electricity. They could also help to vegetate deserts, in a number of ways. 

The vortex towers that I envisage would be a cross between the and the Solar Tower by Making a spiral groove inside the surface of the tower could enhance the vortex updraft effect. This has all been discussed for years, e.g. in the Economist Sept. 29, 2005. 

Vortex towers can produce huge amounts of electricity, that can be used for purposes such as:

  • Desalination of sea water and transport of the resulting fresh water into the desert

  • Capturing CO2 from ambient atmosphere and capturing CO2 produced in the process of making biochar. The CO2 could be used for cloud seeding, carbon building material and char (see below). 

  • Surplus water could also be sprayed into the sky, using the vortex tower's updraft, to further induce cloud formation to create both albedo change and rain.

  • Split the water into hydrogen and oxygen, by means of electrolysis. The hydrogen could then be used as fuel, or to produce ammonia by drawing nitrogen from the air. The ammonia could then be used to produce fertilizer.

  • Carbon that is captured from the atmosphere could be turned into char, similar to biochar, with its benefits as a soil improver and as a safe way to store carbon. This char could be applied to the soil simultaneously with olivine dust and fertilizer as produced in the way described above. Application of such fertilizer together with char could not only reduce the need for fossil fuel-based fertilizers, it can also reduce runoffs that cause N2O emissions and dead zones in the sea, since the char will improve retention of fertilizer in the soil. The carbon could even be combined with ammonia to produce urea, and all this fertilization would benefit vegetation growth. 

Apart from producing electricity, a vortex tower could also push dry, hot air high up into the sky. Some of that heat would escape into space, while the updraft could also establish an air circulation pattern in which hot air would move, high up in the sky, towards the ocean. Simultaneously, as part of this air circulation pattern, air from above the ocean would be drawn - closer to the ground - towards the vortex tower. This air circulation could bring cold and moist wind into the desert, which would benefit vegetation growth.

The benefits of vegetating desert are many; it would take CO2 out of the atmosphere, it could produce food and vast areas could be made suitable for many plants, animals and people. By selling land for settlement, projects to vegetate the deserts could pay for themselves, as part of the Biochar Economy

Projects that involve afforestation, water desalination, biochar production, olivine grinding and building of vortex towers don't require access to high-tech equipment or scarce resources. This means they can be started at many places around the world, with many global benefits.

Forests have many benefits. Trees take carbon out of the atmosphere to grow. Trees can provide food and building material. Forest waste can be turned into biochar. Forests can have a cooling effect by shading the soil, thus preserving moisture. Furthermore, forests release volatile organic compounds that can have beneficial effects, as follows:
When you're walking through a forest you can smell a kind of piny odour and that's because of these other compounds, volatile organic compounds. And they're things like isoprene, monoterpenes.

When they're released into the atmosphere they undergo reactions with a class of compounds called oxidants and that's things like ozone. Following those reactions they're able to form tiny particles in the atmosphere.

While they're present in the atmosphere they can kind of interact with incoming solar radiation - the energy from the sun essentially and kind of perturb its path so that it doesn't make it to the earth's surface and scatters it.

Additional to this is the role that these particles play in brightening the clouds that are above the forests. And they do this because when they're in the atmosphere they grow and they get to a certain size where they're able to form cloud droplets. And the more of these droplets that there are in a cloud the whiter and brighter that it becomes. And that means that it will reflect away more of the incoming solar radiation that's falling on that particular part of the earth's surface.
[italics part edited from National Environment Research Council, May 18, 2011, podcast and transcript

Read more at:
Afforestation - bringing life into the deserts

Earlier posted at knol (meanwhile discontinued by Google) by Sam Carana, October 12, 2011. 

Tuesday, March 27, 2012

The Biochar Economy

The Biochar Economy offers a sustainable alternative to economic systems that fail to sufficiently take into account care for the environment and concerns for global warming.

Biochar is one of the products of pyrolysis, an oxygen-starved method of heating up biomass to (also) produce renewable energy.  

The Australian Government plans to award carbon credits for the application of biochar to soil, for biochar's ability to abate greenhouse gases. As part of the Carbon Farming Initiative $AU2 million will be provided for a Biochar Capacity Building Program. This in addition to $AU1.4 million that is already being invested in the National Biochar Initiative as part of the Climate Change Research Program.

Carbon credits constitute just one way to support biochar. Ultimately, carbon credits are typically paid from profits on fossil fuel, which are scheduled to decrease over time. To develop more lasting support for biochar, alternatively policies should be considered.
The Biochar Economy

The idea behind the "Biochar Economy" is to try to embed biochar production into as many processes as possible, as pictured on above image, from open source ecology.

In carbon-negative 'Biochar Economies', biochar is proposed to also act as a kind of local 'gold standard' for local currency supply. Biochar-based currency could strengthen local economies and shield them not only from the volatility of global currency fluctuations, but also from the danger of global warming causing the entire global financial system to collapse, as discussed back in 2007.

Biochar-based local currencies go well together with three types of local feebates: 
  • Energy fees, imposed on polluting fuel and the equipment and appliances used to burn the fuel, to fund rebates on local clean energy programs.
  • Fees on polluting cement, livestock products and nitrogen fertilizers, made payable in local currency, funding rebates on locally-produced biochar and olivine added to local soils.
  • Local rates that incorporate feebates, i.e. higher fees the lower the soil's carbon content, with rebates for soils with the highest carbon content.
Since pyrolysis of surplus biomass can produce renewable energy, it can benefit from local energy feebates as pictured below. 

In addition, soil supplements that include biochar can benefit from feebates as pictured below. 

These policies will avoid emissions and effectively take greenhouse gases from the atmosphere. 

These policies will also create local employment and investment opportunities without having to borrow money elsewhere, and will increase local standards of living and health, as well as increase the quality and value of the land. 

All this can be achieved though mechanisms that work in parallel and are often complementary, e.g. pyrolysis of forest waste can stimulate forest growth, avoid termite infections and reduce the risk of wildfires; furthermore, when pyrolysis provides power that replaces the practice of burning firewood and fossil fuel to power lighting and cooking, this will also reduce the risk of lung infections.

To increase demand for the local currency, rebates on local clean energy programs and soil supplements could be paid out in local currency. Furthermore, a community can call for local rates and fees on products such as fuel, polluting cement, livestock products and nitrogen fertilizers to be paid in local currency.

Much crop is now used to grow feed for livestock ― less livestock could free up land that could be used to produce food & wood, and the associated organic waste. Furthermore, such feebates can avoid soil erosion and deforestation, and instead result in more vegetation, thus further increasing the amount of biomass available for pyrolysis.

Below are some further ways pyrolysis can be integrated in the local economy:

  • Pyrolysis of biomass is an excellent way of handling organic waste, while producing useful products such as biochar, biooils and gases such as hydrogen. Biooil and hydrogen can be used to power aviation and shipping.  
  • Bioasphalt® is a type of asphalt made from bio-oil. According to its manufacturer, it can save energy and money, since it can be mixed and paved at lower temperatures than conventional asphalt. 
  • Apart from burial of biochar to enhance soil fertility, biochar can also be used to manufacture a range of products, including vehicle bodies made of carbon fiber and capacitors. 

    A team at Stevens Institute of Technology has designed, fabricated, and tested a prototype supercapacitor electrode made from biochar. The team demonstrated biochar's feasibility as an alternative to activated carbon for supercapacitor electrodes. Currently, supercapacitors use activated carbon. The team estimates that biochar costs almost half as much as activated carbon, apart from being more sustainable. 

    Supercapacitors can be used to power electric buses. Ultracapacitor buses by Sinautecus have been operational in the Greater Shanghai area since August 2006, as mentioned under this post on electric bus systems.