Monday, December 8, 2008

Floating Offshore Wind Power

Matthew Simmons has received quite a bit of press in the past week, after his Ocean Energy Institute floated a proposal to build a $25 billion, 5 GW wind farm in the Gulf of Maine.

Offshore wind farms have a number of advantages over their land based equivalents - they are less hazardous to wildlife, have fewer objections raised on NIMBY concerns and winds are generally stronger over the oceans than they are over land.

Ideally, offshore wind farms will be far enough away from land to avoid being seen from the shoreline, eliminating any residual objections from local residents. Current offshore projects tend to site turbines in waters less than 20 metres deep - going further offshore would mean locating them at depths of 50 meters or more, which is too deep to build supporting towers or trusses down to the sea floor at an affordable cost.

A solution to this problem is floating platforms - one of the key elements of the Ocean Energy Institute proposal. In this post I'll look at some of the work being done to develop floating offshore wind power platforms in order to enable these sorts of schemes to become a reality.

Floating Wind Turbines

According to a 2006 report by the U.S. Department of Energy, General Electric and the Massachusetts Technology Collaborative, offshore wind resources on the Atlantic and Pacific coasts of the United States exceed the current electricity generation of the entire U.S. power industry. NASA has also been investigating ocean wind strengths worldwide, using the QuikSCAT satellite.

Researchers at MIT and elsewhere have been investigating the feasibility of "tension-leg" platforms for wind turbines, a technology that oil companies have been using for deep-water rigs. The structures would be assembled at a shipyard and placed on large floating cylinders that are ballasted with high-density concrete (to keep the structure from tipping over) and then tugged out to sea. Once in location, steel cables would be attached to the platform, anchoring it to the sea floor.

The MIT researchers claim that large turbines located far offshore could eventually generate cheaper power than both land based wind farms and near-offshore ones (even taking into account the increased cost of longer underground electricity transmission cables). Part of the cost advantage is the higher capacity factor achieved due to more consistent offshore winds - potentially averaging between 40 percent and 50 percent compared with 30 percent or less with land based turbines.

Some offshore wind farms could also have advantages in terms of proximity to large coastal cities compared to wind farms in remote areas, which require grid transmission upgrades to transport the power to places where it is consumed. Floating offshore wind farms also avoid bottlenecks in the supply of marine construction equipment such as pile drivers and cranes that may hamper rapid expansion of shallow offshore wind structures (however they may instead compete for some resources with offshore oil exploration and production, which could be problematical in the short to medium term).

A number of companies are active in the area of floating offshore wind technology - primarily Blue H Technologies, StatOil Hydro and SWAY.

Blue H Technologies

Blue H Technologies is a Dutch company that launched their first test platform at Tricase off Italy's southern coast late last year. The company has also announced plans to install another test turbine off Massachusetts.

The Blue H test platform in Italy is a tension-leg platform - a conventional offshore oil and gas platform design that floats below the surface, held in place by chains running to steel or concrete anchors on the seabed. The platform is located 10 km offshore and hosts an 80-kilowatt wind turbine which is mounted with sensors to record the wave and wind forces experienced by the equipment.

Blue H is now constructing a commercial wind farm for the Tricase site, which will have an installed capacity of 92 MW.

Blue H's design is unusual in that the turbine has a two-bladed rotor rather than the conventional three-blade design used elsewhere in. Technology Review has quoted Martin Jakubowski, Blue H cofounder and chief technology officer, as saying that "the noise and jarringly high rotation speeds that made two-bladers a loser on land are either irrelevant or a plus offshore" and that the fast rotation is "less susceptible to interference from the back-and-forth swing of the platform under wave action" and means less torque, resulting in a lighter structure (Blue H's 2.5-megawatt turbine will weigh 97 tons - 53 tons lighter than the lightest machine of the same power output on the market).

Tech Review also quotes Jakubowski as estimating that Blue H's wind farms will "deliver wind energy for seven to eight cents per kilowatt-hour, roughly matching the current cost of natural gas-fired generation and conventional onshore wind energy".

StatOil Hydro

Norwegian oil and gas producer StatoilHydro and Germany's Siemens (a major wind-turbine producer) are partnering in a project to build a commercial-scale floating wind farm about 10 kilometers offshore from Karmøy on Norway's southwestern tip.

StatoilHydro initially plans to operate a 2.3 MW wind turbine atop a conventional oil and gas platform, and is hoping for this to be operational in late 2009. Unlike the Blue H design, StatOilHydro is using traditional wind turbines.

The company believes floating wind farms are the way of the future, with a company spokesman saying that there are a declining number of sites available onshore and in shallow waters and citing regions without a shallow continental shelf like California, Japan and Norway where traditional offshore wind is not possible.

StatOilHydro says that deepwater wind power will be expensive in the initial stages but that the economics could eventually rival those of conventional wind power.

If deep offshore wind power in the North Sea proves to be successful it would become a major component on the planned European Supergrid, which backers hope will link up the region's power networks and allow a much higher proportion of renewable energy in future (possibly entirely fossil-free, as it will need to become eventually).


SWAY, based in Bergen, Norway, plans to field a prototype of its floating wind turbine in 2010. SWAY's platform is basically a spar buoy that can rise and fall gently with wave action, requiring less anchoring than the tension-leg platform. The buoy, mounted on a column nearly 200 meters tall, is held in place by a 2,400-ton gravel ballast. A three-bladed turbine is used, but, unlike conventional onshore turbines, it faces downwind rather upwind to better accommodate heeling of the tower, which may make it more effective in rougher waters than alternative designs.

The Simmons Plan

The cost estimated for Simmons' plan is $5 billion per gigawatt — more than double the amount that T. Boone Pickens’ now delayed wind farm in Texas is supposed to cost.

This seems high if the cost savings expected by the companies mentioned above eventuate, with the StatOilHydro experiment probably being the best guide, with the North Sea facing similar weather challenges to those experienced off New England.

Winter winds in the Gulf of Maine carry as much as eight times more energy as summer breezes, meaning maximum power is available during periods of greatest demand. About 80 percent of Maine residents use oil to heat their homes. The average family uses about 1,000 gallons, or 3,785 liters a year - when prices are around $4 a gallon ($1 a litre) this consumes about one-tenth of the average family's annual income, leading Simmons to declare "If we don't do this, we're [eventually] going to have to evacuate most of Maine".

Seen in that light, even an expensive offshore wind farm is better than the alternative.

As an added bonus, construction and maintenance of the structures will bring valuable job opportunities to a region hard hit by the decline of the fishing industry.

Related Posts :

The Oil Drum - Alternative Wind Power Experiments - SkySails and Airborne Wind Turbines (Peak Energy)

The Oil Drum - Offshore Wind

Tuesday, November 25, 2008

Low Temperature Geothermal Power

The ABC recently had a report on plans to power north-west Queensland with low temperature geothermal power using hot water from the Great Artesian Basin.

A Brisbane-based company says it could supply geothermal power to all of north-west Queensland. Clean Energy Australasia wants to build a $50 million geothermal power station near Longreach. But it has now also revealed plans to build a pilot geothermal project near BHP's Cannington mine at McKinlay, south of Cloncurry. The company's Joe Reichman says the Mount Isa region needs about 500 megawatts of power a year and geothermal resources could easily provide that. "It'll change the region into a powerhouse," he said. Mr Reichman says the company has applied for federal and state government grants and has support from the major mining companies in the region. If the projects proceed they would be the first geothermal power plants in Australia.

Low temperature geothermal power is a relatively new (and very low profile) form of extracting energy from geothermal sources that provides yet another option for meeting our energy needs cleanly and sustainably.

Low Temperature Geothermal Power

When geothermal power is mentioned, people usually think of traditional high temperature geothermal power stations using water from volcanic areas, such as those found in Iceland, New Zealand, the US and elsewhere around the ring of fire.

More recently, interest in enhanced / engineered geothermal systems (EGS) - also known as hot dry rock (HDR) or hot fractured rock (HFR) geothermal power - has been high, with a number of experimental projects underway in Australia and Europe.

Low temperature geothermal power is also starting to attract significant interest, as lower temperature water resources are common in many countries (for example, waste hot water produced by oil and gas wells - in Texas alone, more than 12 billon barrels are produced, with oil companies usually re-injecting the waste water into the earth) and new technologies are beginning to appear that allow these resources to be developed commercially.

UTC Power has developed a low-cost Rankine cycle system that can convert temperatures as low as 195 °F (91 °C) into electricity. The technology is similar to a steam engine, with steam or hot water vaporizes a hydrofluorocarbon refrigerant that drives the turbine (it has been compared to a "refrigerator compressor running backwards").

Geothermal Power In The Great Artesian Basin

The Great Artesian Basin provides the only reliable source of water through much of inland Australia. The basin is the largest and deepest artesian basin in the world, covering a total of 1,711,000 square km. It underlies 23% of the continent, including most of Queensland, the south-east corner of the Northern Territory, the north-east part of South Australia, and northern New South Wales. The basin is 3000 metres (10,000 ft) deep in places and is estimated to contain 64,900 cubic kilometres of groundwater.

Most recharge water enters the rock formations from relatively high ground near the eastern edge of the basin (in Queensland and New South Wales) and very gradually flows towards the south and west. Because the sandstones are permeable, water gradually makes its way through the pores between the sand grains, flowing at a rate of one to five metres per year. Discharge water eventually exits through a number of springs and seeps, mostly in the southern part of the basin. It takes up to two million years for water to travel to the springs in the Lake Eyre area.

Temperatures of the artesian groundwater (which is generally of a very good quality) range from 30o to 100o C at the well heads. As the groundwater is too hot for town water supply and for stock to drink, it needs to be cooled down before consumption. That is why cooling towers can be seen throughout the region.

The ABC report's claim that the Longreach plant would be Australia's first geothermal power plant is incorrect.

A small (120 kW) power station (pdf) has been in operation at Birdsville in western Queensland since the early 1990's - one of the few low-temperature geothermal power stations in the world. The plant derives its energy from the near-boiling (98 degrees C) water taken from the Great Artesian Basin (at a depth of 1230m) that provides a water supply for the town. Operation of this geothermal power station reduced the town's diesel consumption by about 160,000 litres per year.

The Victorian town of Portland (in the Otway Basin) also operated a district heating scheme using water from geothermal sources for about 20 years, though this did not generate power.

Geothermal Power In The United States

The UTC plant has been trialled at the Chena Hot Springs in Alaska, with the first plant going online in July 2006. A second unit began operating later that year. Together, the two power units are contributing to the resort owner's goal of making Chena the first totally renewably powered and fueled community in the United States. The Chena experience is motivating other cities in Alaska, including Anchorage to investigate setting up larger scale geothermal plants.

UTC installed more production systems at another location in New Mexico in August this year.

Utah company Raser Technologies is looking to build a range of geothermal power plants throughout the western United States using Rankine cycle systems, with their first plant going live in Utah earlier this month.

Some oil fields also produce hot water which can be used to drive Rankine cycle power plants, with trials being performed in Wyoming.

Geothermal Power In Germany

Germany is interested in deriving significant amounts of energy from both EGS / HFR and low temperature geothermal sources. There are already four small geothermal power plants successfully operating in Germany, albeit supplying only a tiny amount of electricity.

The first geothermal plant to start operating in Germany is situated in Neustadt-Glewe in the north-eastern part of the country. The 230-kW combined electricity and heat power plant started up in 2003 and extracts water with a temperature of 97 °C from a well 2250 meters under the ground. It supplies 1,300 households with heat and a further 500 households with electricity.

Other plants now operating are the 3.5-MW plant at Unterhaching close to Munich, in Bavaria which is the first geothermal plant in Germany to use Kalina cycle technology. At that plant water is extracted at a temperature of 122 °C from a well 3,500 meters deep. Another 2.5-MW plant in Landau taps water of 150°C that is located 3,000 meters beneath the ground. Another 550-kW plant is due to go into operation in Bruchsal shortly, extracting water at temperatures of 128°C from a well 2500 meters deep.

More plants (as big as 8-10 MW) are due to go into operation in 2009-2010 in Sauerlach, Dürrnhaar, Riedstadt, Speyer, Gross Schoenebeck and Mauerstetten. By 2015 there could be more than a hundred plants operating - around 150 geothermal power plant projects are in the pipeline according to the German government. One major constraint on expanding the program has been shortages of drilling equipment.

Geothermal Power In New Zealand

While New Zealand already generates a significant portion of its power using traditional geothermal sources, the country is also conducting a NZ$2.6 million research program into low temperature geothermal power.


Low temperature geothermal power has the advantage of being clean, continuously available energy that can be generated in a wide variety of locations.

Plants will likely to continue to be relatively small-scale, making it a classic distributed energy generation alternative (like biogas and solar PV), with growth probably remaining low profile for some time.

In the long run, I expect we'll see a useful and significant amount of our energy needs being produced using this technology.

Saturday, November 1, 2008

Making Australia A Better Place

Project Better Place founder Shai Agassi was in town last week announcing that Australia will become the third country to implement the group's vision of electric vehicles powered by renewable energy, following Denmark and Israel.

Better Place and Macquarie Capital Group will raise $1 billion to build a network of 250,000 charging stations and battery exchange stations in key locations along the east coast by 2012. The network will be powered by wind turbines owned by AGL Energy.

Agassi has been promoting the plan as a way to reduce our dependence on oil (the starting premise for the project was "how do you run an entire country without oil") while creating jobs and boosting the local economy (see this interview on the Today Show for his explanation). Operating in Australia will also help the group prove it can work in large countries as well as the much smaller geographical areas covered in the first 2 rollouts. Agassi also noted that the Federal Government's $500 million Green Car Innovation Fund played a part in encouraging them to set up in Australia.

Green Car Congress describes the Better Place network as consisting of three primary components:
  • Charge points. These are to charge batteries with power, providing 160 kilometres of driving range, according to the company. Better Place is planning a 2.5:1 ratio of charge spots to cars.

  • Battery switching stations. For trips longer than 100 miles (161 km), Better Place plans to build roadside battery switching stations. Stations are to be completely automated, and the driver’s subscription takes care of everything. The driver pulls in, and the depleted battery is replaced with a fresh one, without anyone having to leave the vehicle. The process takes less time than it does to fill a tank of liquid fuel, according to the plan.

  • Software to automates the charging and exchange process.

Better Place has a partnership with the Renault-Nissan Alliance to provide electric cars. The prototype electric eMegane sedan features a 160+ kilometre range.

Better Place says it is committed to open network access and using industry standard, with the goal being to allow customers to have a choice of make and model of car.

Automotive Energy Supply Corporation (AESC, a joint venture between Nissan Motor, NEC Corporation, and NEC TOKIN Corporation) and A123Systems have been identified as lithium-ion battery providers to the system.

Better Place plans to own and operate the batteries and power generation (via AGL Energy, in Australia's case), and to sell kilometres travelled to drivers on a subscription basis, in similar fashion to the mobile phone industry.

Better Place in Australia plans to start by setting up charging stations in the Melbourne, Brisbane and Sydney, and then connect them with "electric highways," with stations set up every 25 miles.

Overall I'm quite excited by this project - though obviously executing the plan, in terms of setting up all the infrastructure and getting a significant volume of electric cars on the market at a competitive price, will be challenging. If the 3 countries piloting the idea can demonstrate it can work successfully, it will provide a blueprint for personal transport in a post-oil world.

Friday, September 12, 2008

Terra Preta: Biochar And The MEGO Effect

This month's edition of National Geographic has a feature article on "Soil", which looks at the steady degradation of agricultural land and the problem this poses in world where the population is heading for 9+ billion people - effectively calling attention to the "peak dirt" problem (however soil is renewable, so any "peak" should be able to be reversed if sufficient time and effort is put into doing so).

The article uses an acronym I've never come across before to describe the problem faced by those trying to draw attention to the issue: MEGO (My Eyes Glaze Over) - a phenomenon which should be familiar to anyone who has ever talked about peak oil, global warming or any of the other "limits to growth".

This year food shortages, caused in part by the diminishing quantity and quality of the world's soil, have led to riots in Asia, Africa, and Latin America. By 2030, when today's toddlers have toddlers of their own, 8.3 billion people will walk the Earth; to feed them, the UN Food and Agriculture Organization estimates, farmers will have to grow almost 30 percent more grain than they do now. Connoisseurs of human fecklessness will appreciate that even as humankind is ratchetting up its demands on soil, we are destroying it faster than ever before. "Taking the long view, we are running out of dirt," says David R. Montgomery, a geologist at the University of Washington in Seattle.

Journalists sometimes describe unsexy subjects as MEGO: My eyes glaze over. Alas, soil degradation is the essence of MEGO.

One subject that features in the article is soil restoration, including a look at "terra preta" - rich, fertile artificial soils found in the Amazon. In this post I'll have a look at modern day techniques to produce terra preta (often called biochar or agrichar) which have the potential to increase soil fertility, generate energy and sequester carbon all at the same time.

The History Of Terra Preta

Terra Preta ("dark earth") was discovered by Dutch soil scientist Wim Sombroek in the 1950's, when he discovered pockets of rich, fertile soil amidst the Amazon rainforest (otherwise known for its poor, thin soils), which he documented in a 1966 book "Amazon Soils". Similar pockets have since been found in other sites in Ecuador and Peru, and also in Western Africa (Benin and Liberia) and the Savannas of South Africa. Carbon dating has shown them to date back between 1,780 and 2,260 years.

Terra preta is found only where people lived - it is an artificial, human-made soil, which originated before the arrival of Europeans in South America. The soil is rich in minerals including phosphorus, calcium, zinc, and manganese - however its most important ingredient is charcoal, the source of terra preta's color.

It isn't entirely clear if the Amazon Indians whose old settlements terra preta is found at deliberately created the soils or if they were an accidental by-product of "slash and smoulder" farming techniques, though the emerging consensus seems to be that the Indians deliberately created the material, with some early European accounts in the area noting the practice still being performed.

The key ingredient is apparently the activated carbon in the charocal. Activated carbon has a complex, spongelike molecular structure - a single gram can have a surface area of 500 to 1,500 square meters (or about the equivalent of one to three basketball courts). Having this material in the soil has several beneficial effects, including a 20% increase in water retention, increased mineral retention, increased mineral availability to plant roots, and increased microbial activity.

It has also been shown to be particularly beneficial to arbuscular mycorrhizal fungi, which form a symbiotic relationship with plant root fibers, allowing for greater nutrient uptake by plants. There is speculation that the mycorrhizal fungi may play a part in terra preta’s ability to seemingly regenerate itself.

Pyrolysis and Eprida

Modern day producers of biochar (agrichar) take dry biomass and bake it in a kiln to produce charcoal. Biochar is the term not for what is left over after the energy is removed: a charcoal-based soil amendment - this process is called pyrolysis. Various gases and oils are driven off the material during the process and then used to generate energy. The charcoal is buried in the ground, sequestering the carbon that the growing plants had pulled out of the atmosphere. The end result is increased soil fertility and an energy source with negative carbon emissions.

Eprida is a company founded by Danny Day, which is attempting to commercialise the idea by building systems that turn farm waste into hydrogen, biofuel, and biochar (see here for a short movie explaining their process).
The Eprida technology uses agricultural waste biomass to produce hydrogen-rich bio-fuels and a new restorative high-carbon fertilizer (ECOSS) ...In tropical or depleted soils ECOSS fertilizer sustainably improves soil fertility, water holding and plant yield far beyond what is possible with nitrogen fertilizers alone. The hydrogen produced from biomass can be used to make ethanol, or a Fischer-Troupsch gas-to-liquids diesel (BTL diesel), as well as the ammonia used to enrich the carbon to make ECOSS fertilizer.

We don't maximize for hydrogen; we don't maximize for biodisel; we don't maximize for char...By being a little bit inefficient in each, we approximate nature and get a completely efficient cycle.

The potential power of biochar lies in this closed loop production process , where agricultural practices involving biochar production see increasing returns of crop yields, energy and soil fertility over time.

Biochar also has potential to address problems such as waste disposal and rural development. A significant proportion of the world's population relies on charcoal as a cooking fuel, the production of which drives deforestation in Africa and other places.

Replacing traditional charcoal kilns with modern pyrolysis units could reduce the demand for wood from forests by increasing the efficiency of energy production and adding the ability to use any source of biomass, including agricultural waste products. This would also help to reduce respiratory diseases in the developing world, particularly amongst children.

There has also been speculation that pyrolysis could be a useful technique for dealing with the huge swathes of Canadian forests that have been killed by pine beetles recently.

Some industry participants believe that energy, rather than agriculture, will be the key driver for adopting biomass pyrolysis. Desmond Radlein of Dynamotive Energy Systems has been quoted as saying "It is wishful thinking that people will switch to renewable fuels unless it is cheaper. All of this is tied to the price of oil; as it goes up, many more things are possible."

Another company active in the pyrolysis sector is Best Energies. Technical Manager Adriana Downey recently had an interview with Beyond Zero Emissions, talking about some of the pilot programs they have been running and plans to build the first fully commercial scale pyrolysis plant in Australia.
Lukas's program with the NSW DPI (Department of Primary Industries) in Northern NSW have basically taken some of the agrichar material that we've made here at Best Energies and they've been trialling that material in different agronomic applications to see how the agrichar, when its applied, can help crop-productivity and improve the sustainability of agriculture as well as, and what you guys are more interested in, sequester carbon long-term in soils and also decrease the potent greenhouse gas nitrous oxide emissions from soil. ...

The agrichar when it's applied to the soil has a good effect on the general physical structure of the soil. Because the agrichar has a really high surface area, it means that there's lots of pores in the soil which can then retain moisture and act as little reservoirs for the water to be retained in the soil. As well as this, all of the surface area helps to bind nutrients in the soil and also provides a microhabitat for micro organisms in the soil which are essential for the natural processes in the soil which allow micro organisms to flourish.

Carbon Capture Potential

There is a large difference between terra preta and ordinary soils - a hectare of meter-deep terra preta can contain 250 tonnes of carbon, as opposed to 100 tonnes in unimproved soils from similar parent material, according to Bruno Glaser, of the University of Bayreuth, Germany. The difference in the carbon between these soils matches all of the carbon contained in the vegetation on top of them.

The ABC's "Catalyst" program last year had a feature on "Agrichar – A solution to global warming ?" (shown below) in the lead up to an international biochar conference in Terrigal, NSW, which included Tim Flannery talking about the potential for sequestering gigatonnes of carbon in the soil.

This year's International Biochar Initiative conference has just been held in Newcastle-upon-Tyne in the UK.

It is not yet clear what the limits are to how much biochar can be added to the soils using these techniques, however some fairly extravagant claims about biochar's capacity to capture carbon have been made. Soil scientist and author of "Amazonian Dark Earths: Origin, Properties, Management" Johannes Lehmann believes that a strategy combining biochar with biofuels could ultimately offset 9.5 billion tons of carbon per year - an amount equal to the total current fossil fuel emissions. Lehmann also notes that unlike biodiesel and corn ethanol, biochar doesn’t take land away from food production.

If true, this would be an interesting form of geoengineering to try and reverse the effects of global warming (and one far less risky than some of the alternatives proposed) but I would still question our ability to turn all the world's oil, coal and gas reserves back into rich soil via burn - atmosphere - pyrolysis loop.


A number of criticisms have been made about biochar. These include:

* The technology to implement the process is still immature.
* Scientists don’t know how much charcoal farmers should use, how they should apply it, or which feedstocks work best.
* Farmers are reluctant to spread unproven products on their fields, so the few companies manufacturing biochar have struggled to find buyers.
* Charcoal production can generate toxic waste if performed incorrectly.
* The energy needed to produce, transport, and bury biochar could outweigh the carbon savings.
* Some analysts say the economics of the process will not be acceptable until carbon markets are established, allowing farmers to earn carbon credits for applying biochar to their fields.
* Some environmental activists claim that applying the process on a large scale would result in further rainforest clearing which would actually degrade soil quality and increase global warming.

Rhizome In The Amazon

Jeff Vail recently had a post on a "Rhizome Template in the Amazon ?", which looked at a paper by Mark Heckenberger suggesting that a dense civilization of networked villages once existed in the Amazon, which Jeff noted was interesting because it "appears to show a form of organization that permits density without significant hierarchy".

The paper shows that the Xingu region of the Amazon was once populated by a grid-like pattern or villages, each connected by a precisely aligned network of roadways (the Xingu river is the Amazon's second longest tributary, with the region currently experiencing tension over plans to dam the river).
Here's an alternate mode of organization--a networked "grid," "lattice," or "peer-to-peer" structure of small, minimally self-sufficient villages, or "rhizome" as proposed in my article The Hamlet Economy. The Xingu settlement structure seems to consicously model itself in the latter pattern. Heckenberger even notes that each village was surrounded by a buffer zone of "managed parkland," exactly the kind of fall-back, resiliency-enhancing production zone that I recommended for rhizome. Here's a link to a satellite image of one section fo Xingu settlement.

Did this Xingu civilization really develop a dense, ecologically sustainable civilization without hierarchal structure? Or did they simply find a new way to impose hierarchy without developing the signatures of "central places"? Was this a conscious reaction to prior abuses of hierarchy, or simply an expedient to survival in the dense forrests and poor agricultural soils of the Amazon? We don't know the answers to these questions at this time, but the research of Heckenberger and his colleagues suggests that there is still a great deal for us to learn from the past about how we can best live in the future

Heckenberger also examined the terra preta pockets in the region, which is described briefly in an interesting article by Charles Mann in The Atlantic Monthly called "1491". Scientific American also notes the correlation between the lost cities of the Amazon and terra preta in "Ancient Amazon Actually Highly Urbanized, as does The Vermont Quarterly in "Pay Dirt".
Terra preta, Woods guesses, covers at least 10 percent of Amazonia, an area the size of France. It has amazing properties, he says. Tropical rain doesn't leach nutrients from terra preta fields; instead the soil, so to speak, fights back. Not far from Painted Rock Cave is a 300-acre area with a two-foot layer of terra preta quarried by locals for potting soil. The bottom third of the layer is never removed, workers there explain, because over time it will re-create the original soil layer in its initial thickness. The reason, scientists suspect, is that terra preta is generated by a special suite of microorganisms that resists depletion. "Apparently," Woods and the Wisconsin geographer Joseph M. McCann argued in a presentation last summer, "at some threshold level ... dark earth attains the capacity to perpetuate—even regenerate itself—thus behaving more like a living 'super'-organism than an inert material."

In as yet unpublished research the archaeologists Eduardo Neves, of the University of São Paulo; Michael Heckenberger, of the University of Florida; and their colleagues examined terra preta in the upper Xingu, a huge southern tributary of the Amazon. Not all Xingu cultures left behind this living earth, they discovered. But the ones that did generated it rapidly—suggesting to Woods that terra preta was created deliberately. In a process reminiscent of dropping microorganism-rich starter into plain dough to create sourdough bread, Amazonian peoples, he believes, inoculated bad soil with a transforming bacterial charge. Not every group of Indians there did this, but quite a few did, and over an extended period of time.

When Woods told me this, I was so amazed that I almost dropped the phone. I ceased to be articulate for a moment and said things like "wow" and "gosh." Woods chuckled at my reaction, probably because he understood what was passing through my mind. Faced with an ecological problem, I was thinking, the Indians fixed it. They were in the process of terraforming the Amazon when Columbus showed up and ruined everything.

Scientists should study the microorganisms in terra preta, Woods told me, to find out how they work. If that could be learned, maybe some version of Amazonian dark earth could be used to improve the vast expanses of bad soil that cripple agriculture in Africa—a final gift from the people who brought us tomatoes, corn, and the immense grasslands of the Great Plains.

All in all I think biochar is worth exploring further in some depth.

Further Reading:

Nature: Putting the carbon back "Black is the new green":

Biochar overview from Cornell University:

Terra Preta web site from the University of Bayreuth

The Earth Science Forum:

Biochar summary from Georgia Tech:

Terra preta mailing list:

FAO: Organic Agriculture And The Environment

WorldChanging: A Carbon-Negative Fuel

Hen and Harvest: Black Magic

Peak Energy: On population growth and the green revolution - "The Fat Man, The Population Bomb And The Green Revolution"

Peak Energy: On worms and soil - "The Turning Of The Worm"

Peak Energy: On Mycelium - "Nature's Internet: The Vast, Intelligent Network Beneath Our Feet"

(Hat tip to Erich J Knight and Aaron Newton for providing some of the links used in the post)

Wednesday, August 27, 2008

Bioplastic - Better Living Through Green Chemistry ?

The New York Times recently had an editorial on Samsung's "Corn Phone", which is being heavily promoted as environmentally friendly as the casing is made from bioplastic. Somewhat to my surprise, they point out that it is neither - firstly because the bioplastic is made from corn (and is thus contributing to the problems that corn based ethanol is causing) and secondly because phones have become nearly throw away items that are rarely recycled.

The electronics industry has been a major polluter, from the manufacturing end to the landfill. The dizzying pace at which consumer electronics become obsolete (What, you're still using that old phone?) compounds the problem. And increasingly rich countries are offloading the disposing, and often the incinerating, of phones and computers to poorer countries.

Unfortunately Samsung's new cellphone relies on a flawed equation: corn equals green. It is really time to throw out this formula for good. Bioplastic derived from corn requires special handling in recycling, and the difficulty of those processes makes them energy inefficient. Bioplastic also creates another market for corn, a much smaller market than the ethanol market, but growing nonetheless. New industrial demands for corn are driving up world food prices and are increasing the pressure to convert more nonagricultural land to corn production.

The truly green solution for electronics makers is to close the loop between manufacturing and recycling: reusing the plastics we so quickly and happily toss away to make new cellphones.

While Samsung's phone doesn't seem to have passed the "greenwash" test, peak oil poses a problem for plastic production for which bioplastic could be one potential solution, so in this post I'll have a look at what is happening in the industry and how our desire for plastics could perhaps be satisfied in a post oil world.

Plastic and peak oil

Chemicals and plastics are an integral part of peak oil concerns, as oil is the primary raw material used in their production, leading to the conclusion that as we pass the peak the shrinking availability and rising price of oil will cause a reduction in supply of these products.

There are 3 basic approaches to dealing with this scenario in a positive way:

1. Substitution: Use other materials - cardboard or paper packaging for example, or going back to using metal eating utensils instead of disposable plastic ones. Many other items currently made with plastic can also be made with wood, glass or metal (or even popcorn).

2. Recycling: Some plastics can be recycled - or converted back to oil for that matter, though the net energy benefit of this is debatable. Plastic recycling is already widely practiced though we have a long way to go before all recyclable plastics reach the correct destination. Recycling plastic not only reduces the amount of feedstock required to make the material, it also reduces the energy required in manufacturing by around 70%.

3. Bioplastics: Use carbohydrates to create plastics instead of hydrocarbons, an endeavour which was historically known as "chemurgy".

By and large, subsititution would often seem to be a good thing in terms of reducing the amount of waste that ends up in our landfills (and the number of nurdles floating around in the oceans), though there are drawbacks like the extra effort and cost required to make objects out of materials that can't simply be injection moulded the way plastics can.

As a result, while substitution and recycling will often be the best way of dealing with the decline in availability of oil as a feedstock for plastic manufacture, we will likely still want to make new quantities of plastic each year - which leads us to bioplastics.

Bioplastic in Context

At this point bioplastics still comprise just a tiny fraction of the overall market, though one growing at an impressive rate of over 20% per year. The European Bioplastics Association says 1.5 million tonnes of bioplastics will be manufactured annually by 2011.

In comparison, according to the NZ plastic industry, 150 million tonnes each year of petroleum based plastics are produced (estimates for total production vary wildly unfortunately - BusinessWeek recently quoted a number of 500 million tons, while Biopact quotes a number of 200 million tonnes).

Plastic production is estimated to consume around 5% of global oil production each year (again, estimates vary quite a lot, and depend on if just feedstock is counted or if the energy to produce the plastic is also included) which represents the largest use outside the transport and energy sectors.

Developments in Bioplastic

Bioplastic developments have been appearing in the news with great regularity in recent years - The Economist recently noted that the number of patents granted for industrial biotechnology now exceeds 20,000 per year - with the rising price of oil increasing interest in them.

While bioplastic is often considered "green", this isn't necessarily true. Even if we ignore the problems associated turning food into packaging (in the case of corn based bioplastics), there are still many forms of bioplastic which aren't biodegradable. There is also the energy required to power farm machinery used in growing biomass feedstock, to produce fertilisers and pesticides, to transport biomass to processing plants, to process the biomass and ultimately to produce the bioplastic - most of which currently comes from non-renewable sources (though this could eventually be remedied, in time).

The best approach for dealing with the limits on bioplastic production (besides the substitution and recycling options) is similar to the approaches Amory Lovins talks about for dealing with the biofuels problem - redesign products so they need less bioplastic, and produce the bioplastic by harvesting from polyculture, perennial crops like switchgrass grown on non-agricultural land.

Designer Phillippe Starck, a recent high profile convert to green thinking (dubbing all his previous work "unnecessary") recently explained his choice of environmentally unfriendly polycarbonate as the material for a new chair design, which should give you an idea of some of the trade-offs currently facing designers considering alternatives to plastics:
Wired: Recently, you have begun to look at the environmental impact of your designs. How does a plastic chair fit in?

Starck: The stupidity of the ecological movement is that people kill trees for wood. It's ridiculous. The best ecological strategy is to make products of a very high creative quality, so you can keep them for three generations. I prefer to make a very good chair in the best polycarbonate than make any shit in wood that will be in the trash one year later.

Wired: Why not use recycled plastic?

Starck: It's a little joke of a material. You can do almost nothing with it. And I also refuse bioplastic, which comes from something that people can eat. Scientists agree that we have a real food problem, a famine approaching. It's a crime against humanity to take something you can eat and make a chair — or use it as gas for your SUV.

There are also some concerns about greenhouse gas emissions, though these seem questionable.

Some examples of bioplastic producers and uses include:

* US company Metabolix, manufacturer of a biodegradable bioplastic called Mirel, has announced that they have genetically engineered a way to generate "significant amounts" of bioplastic by growing it in directly in the fast growing perennial plant switchgrass. Metabolix is also looking to use a technology developed in Queensland to produce plastic from sugarcane (without affecting sucrose production) at a cost of $1 to $2 per kilogram.

* Mazda is looking to use cellulose based bioplastic in cars from 2013.

* Australian firm Plantic produces a biodegradable bioplastic from corn starch which is used in packaging, using a technology developed by the CSIRO.

* US firm NatureWorks (a subsidiary of agribusiness giant Cargill) has opened a factory in Nebraska, producing 140,000 tonnes of a biodegradable plastic known as PLA, using corn starch. Wal*mart is a major customer, using the material for food containers.

* Dow (the world's largest producer of conventional plastics), is building a factory in Brazil that will produce polyethylene using ethanol made from sugarcane. It is due to open in 2011 and will produce 350,000 tonnes of the material a year. The Times quotes a Dow spokesman as saying that using sugarcane to make polyethylene (rather than the usual naptha-based crude oil or natural gas) is economic with oil prices even when they are at $45 per barrel.

* Brazilian company Braskem is also aiming to produce 200,000 tonnes of polyethylene a year from ethanol.

* NEC has developed a recyclable bioplastic which remembers its shape

* Researchers at New York's Polytechnic University have genetically engineered a bioplastic that can be converted into biodiesel after it has been used, resulting in funding from DARPA and interest from the US military.

* A process developed at the University of Waikato in New Zealand will allow animal waste like blood meal and feathers to be turned into a biodegradable plastic.

* Researchers at Iowa State University and Cornell are looking at using nanoclay particles and nanotechnology techniques to make bioplastics that biodegrade faster and have improved mechanical properties (such as strength).

* Novomer is trying to commercialise a process developed at Cornell for producing bioplastic from carbon dioxide and orange peels (a rare useful example of carbon sequestration).

* Canada's National Research Council is researching the use of bacteria that produce bioplastic from maple syrup and sap, harnessing the large surplus of syrup.

* Fabric manufacturer Interface is looking to make plastic from potatoes in Maine.

* Japanese firm NTA is looking to produce bioplastic from Kenaf grown in Queensland.

* The rising price of polyurethane is causing some surfboard manufacturers to turn to plant based biofoam.


The 5% of oil consumption that is related to plastic production seems to be a form of low hanging fruit that we could dispense with fairly easily, with a combination of mandating the use of recyclable plastics and/or bioplastics and making sure that materials are recycled wherever possible, while also looking to be more efficient in our usage of the stuff in the first place.

Bioplastics aren't a silver bullet in this respect but they are a useful tool for helping to eliminate one form of oil usage, so I think they should be encouraged and promoted - particularly biodegradable versions manufactured from non-food crops or waste.

Thursday, August 21, 2008


This blog is intended as a companion to my regular haunts at Peak Energy and The Oil Drum (ANZ).

Its purpose is to collate my longer posts on clean energy and related subjects, which I intend (and have been for some time) to eventually condense into a single post called "Our Clean Energy Future" which outlines my view of how to solve peak oil, global warming and related problems.

The posts will still appear at PE and TOD ANZ, but the idea is that they won't be drowned out by the clutter of day to day posts at those 2 blogs.

Relevant posts that have appeared previously include articles on:

* Concentrating Solar Thermal Power - Concentrating on the important things: Solar Thermal Power (TOD ANZ)

* Thin Film Solar Power - Thin Film Solar Power - Cheaper than Coal ? (TOD ANZ)

* Alternative Wind Power - SkySails And Airborne Wind Turbines (TOD ANZ)

* Tidal, Wave and OTEC Power - Tapping The Source - The Power Of The Oceans (TOD ANZ)

* Geothermal Power - Geothermia (TOD ANZ)

* Biogas - Banana Methane Powered Cars, Pig Poo Power And Other Uses For Biogas (TOD ANZ)

* Gas in Africa's great lakes - Turning Danger Into Power (TOD ANZ)

* Smart Grids (a much longer version will follow soon) - Smart Grids

* Green Buildings - Bright Green Buildings and Dark Green Buildings

* Electric Cars - Electric cars companies ready to take over the road

* Cogeneration / CHP - Cogeneration At Home: Ceramic Fuel Cells (TOD ANZ)

* Biochar / Pyrolysis - Black Earth

* Bioplastics (a revised version will follow soon) - Better Living Through Green Chemistry

* The Limits To Growth - The Limits To Scenario Planning (TOD ANZ)

* Hydrogen - The Hydrogen Economy And Peak Platinum (TOD ANZ)

* Storing Energy Using Graphite - Storing Energy Using Graphite (TOD ANZ)

* Storing Energy Using Ammonia - We're Off To See The Wizard - Storing Energy Using Ammonia (TOD ANZ)

* Solar Powered Desalination - Solving Our Water Problems - Desalination Using Solar Thermal Power (TOD ANZ)

* Salt Water Power - The Power Of Osmosis

* Artificial Meat - A Post Peak Protein Possibility: The Meat Beast