Monday, May 18, 2009

Towards a Sustainable Economy

Cycle A: Inorganic Waste

We're all familiar with the idea that we're running out of scarce resources. We just cannot continue to keep drilling and mining for more fossil fuel, metals and other resources. One way to deal with scarcity is to recycle resources, i.e. separating waste to extract metals, glass, plastic, concrete, bricks, etc. This type of recycling is possible for much of our inorganic waste. In the light of global warming and health concerns, however, a shift to organic resources and renewable energy seems a better approach(1).

Cycle B: Organic Waste

Recycling organic waste constitutes another cycle in a sustainable economy. Many people now compost kitchen and garden waste, thus returning many nutrients to the soil. However, such composting does release a lot of greenhouse gases. A cleaner alternative is to pyrolyze organic household waste, farm waste and forest waste. Pyrolysis is an oxygen-starved method of heating waste at relatively low temperatures that will result in the release of little or no greenhouse gases. With pyrolysis, organic waste can be turned into hydrogen and agrichar(2).

Estimates are that some 363 tonnes of CO2 per hectare can be locked up in the soil in the form of agrichar(3). Since the U.S. has some 475 million hectares of agricultural land(4), huge amounts of carbon could be stored in this way.

NASA-scientist Jim Hansen calculates that reforestation of degraded land and improved agricultural practices that retain soil carbon could draw down atmospheric carbon dioxide by as much as 50 ppm(5).

Cycle C: Clean Energy

We should also replace fossil fuel by clean and safe energy, in order to reduce greenhouse gas emissions. Obvious ways to do this are to install more solar and wind facilities. Pyrolysis can also produce fuel to power transport. Hansen calculates that this and using carbon-negative biofuels could bring carbon dioxide back to 350 ppm well before the end of the century(5).

Surplus energy can close this cycle, leading to a range of new and clean industries, such as water desalination(6) which could in turn result in the production of lithium for car batteries and magnesium for clean concrete(7).

Electrolyzers can now be made without a need for platinum(8)(9) and there's also interesting research into using electricity to turn seawater into hydrogen by means of electrolysis(10). When vehicles run on hydrogen, their output is clean water, rather than emissions.

Surplus Energy

As the number of wind turbines grows, there will increasingly be periods of time when turbines produce more energy than the grid needs. Especially at night, when demand on the grid is at its lowest, there can be a lot of wind. Unless this energy can somehow be stored or used otherwise, it will go to waste.

Similarly, surplus energy can be produced by solar power facilities. Especially in the early hours of the morning, just after sunrise, the sun can shine brightly, yet there's little or no need for electricity on the grid. It makes sense to store surplus energy at wind farms in molten salt facilities.

Surplus energy from wind turbines can be used for purposes such as:

  • water desalination

  • storage (i.e. for later use)

- car batteries
- pumped-up water

- flywheels(11)
- compressed air
- hydrogen

  • carbon air capture(14)(15)

  • spraying seawater into the sky, to change albedo above oceans(16)

Cycle D: Air Capture

Surplus energy can also power air capture devices. With air capture devices, carbon dioxide can be captured from ambient air. By carrying air capture devices, vehicles can contribute to removal of carbon dioxide from the air. Alternatively, a fee could be imposed on vehicles, with the proceeds used to fund air capture elsewhere(17).

Captured carbon dioxide can be used for purposes such as fueling greenhouses, fueling transport, producing agrichar and supplying carbon to industry, for manufacture of building material, plastic, carbon fiber and other products.

Towards a sustainable economy

Towards a more sustainable economy

In conclusion, there are sustainable ways to do things and to a large extent they do complement each other. Moreover, they are environmentally and economically sustainable, with good job opportunities and investment potential.

However, since they do complement each other, each of these industries is now waiting for the other industries to mature first. To break this chicken-and-egg situation, government should develop an industry policy that uses the bigger picture of these four cycles of a more sustainable economy.

Feebates(17) can achieve the shift we need most effectively, and they only need to insist that such new industries are safe and clean; market mechanisms can further sort out what works best where.


1. The Next Industrial Revolution - Bill McDonough and Michael Braungart

2. Agrichar / Biochar / Terra Preta - Wikipedia and Sam Carana

3. Burying biomass to fight climate change - NewScientist, 03 May 2008

4. An Overview of U.S. Farm Real Estate Markets

5. Target Atmospheric CO2: Where Should Humanity Aim? - J. Hansen, et al.

6. Desalination with zero sea discharge - CSIRO Australia

7. Carbon-negative building - by Sam Carana

8. ITM Power update

9. Breakthroughs open door to Hydrogen Economy - by Sam Carana

10. Team wins $4m grant for breakthrough technology in seawater desalination

11. PowerStore

12. Iceland launches energy revolution

13. Norway has long produced ammonia by electrolytic hydrogen using hydroelectricity, in:
A Great Potential: The Great Lakes as a Regional Renewable Energy Source - Bradley, David (2004)

14. Removing carbon from air - by Sam Carana

15. Can Technology Clear the Air - NewScientist

16. Combat Global Warming with Evaporative Cooling - by Sam Carana

17. Feebates

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