Science in Society Archive

How to be Fuel and Food Rich under Climate Change

Dr. Mae-Wan Ho rejects solutions offered by governments and tells us how to survive the climate change and energy crisis in style

Governments spinning for the next big solution

The end of cheap fossil fuels and the rapidly widening gap between supply and demand have sent our governments into a tailspin for the next big solution. Tony Blair wants to give Britain nuclear power, and you’ve heard Peter Saunders on why not (“Nuclear power: A leap into the dark energy chasm”, this series).

George W. Bush is offering the United States biofuels: ethanol from corn, sugarcane and hopefully, wood biomass; and biodiesel from soybeans, sunflower and other oil seeds (“Biofuels for oil addicts”, SiS 29).

A “billion ton vision” was unveiled [1] to make available 1.3 billion tons of dry biomass for the biofuels industry by the middle of this century, to provide 30 percent of the country’s fuel use. It comes with all kinds of optimistic assumptions, such as a fifty percent increase in crop yield.

Europe, too, has set a target of 5.75 percent of EU’s transport fuel as biofuels by 2010, increasing to 8 percent by 2015.

Biofuels Corporation plc is here in Britain. The first 250 000 Mt biodiesel processing plant is nearing completion at Seal Sands Middlebrough on the northeast coast of England, and it will be using vegetable oil crops [2].

Biofuels from energy crops are bad news

Biofuels from energy crops are bad news, as our Energy Review makes clear ( To sum up: there isn’t enough land to grow energy crops and food crops. The pressure on land will accelerate deforestation, and cause huge increases in carbon emissions, so biofuels won’t be carbon neutral as claimed. Bioenergy crops will destroy biodiversity, and accelerate global warming and species extinction. Above all, they will threaten the food security of the poorest nations, and raise food prices for all countries as food and energy compete for the same ‘feedstock’. Bioenergy crops are also unsustainable, as they deplete soil minerals and reduce soil fertility especially in the long term. They generally give small to negative energy returns when you do the life-cycle analysis properly. The processing wastes have substantial negative impacts on the environment. And although biodiesel is cleaner than diesel, ethanol is not; it generates mutagens and carcinogens and increases ozone levels in the atmosphere.

There is no spare land for bioenergy crops

Calculations based on the best-case scenario of unrealistically high crop yields and high recovery of biofuels from processing still end up requiring 121 percent of all the farmland in the United States to grow enough biomass to substitute for the fossil fuels consumed each year [3].

The EU target of 5.75 percent biofuel substitution for fossil fuels will require at least 14 to 19 percent of farmland to grow bioenergy crops [4]. There will be no set-aside left to protect natural biodiversity, as that’s only 12 percent of farmland in the EU. So, what will that do to our butterflies, birds and bees?

The latest satellite data reveal that 40 percent of the earth’s land is already used up for agriculture [5], either growing crops or for pasture. There is no spare land for growing food, let alone bioenergy crops.

Biofuels and deforestation

Greenpeace has photographed a horrific aerial view of the vast swathes of the Amazonian forest in Brazil cleared for soybean cultivation. A sample of press reports indicates things are getting worse.

Fred Pearce wrote in the New Scientist November 2005 [6]: “From the orang-utan reserves of Borneo to the Brazilian Amazon, virgin forest is being razed to grow palm oil and soybeans to fuel cars and power stations in Europe and North America. And surging prices [of fossil fuels] are likely to accelerate the destruction.”

“The expansion of palm oil production is one of the leading causes of rainforest destruction in south-east Asia,” said Simon Counsell, direction of UK-based Rainforest Foundation.

George Monbiot, writing in The Guardian December 2005, quoted from Friends of the Earth Report that between 1985 and 2000 the development of oil-palm plantations was responsible for an estimated 87 percent of deforestation in Malaysia. In Sumatra and Borneo, 4 million hectares of forests were lost to palm farms; and now a further 6 m ha are scheduled for clearance in Malaysia and 16.5 m ha in Indonesia [7]. These forests are home to the orang-utan, the Sumatran rhinos, tigers, gibbons, tapirs, proboscis monkeys and thousands of other species, all of which could become extinct. Thousands of indigenous people have been evicted and 500 tortured when they tried to resist. The entire region is being turned into a gigantic vegetable oil field.

Biofuels and food price hike

The confederation of the food and drink industries of the EU has already expressed concern over the price increases for food ingredients, especially rapeseed [8]. The rapeseed oil prices were recently up 45 percent and demand within the EU is forecast to increase by 25 percent. Cereals prices are also predicted to go up.

In the United States, huge amounts of corn go to produce ethanol, and corn and ethanol are heavily subsidized at both the state and federal levels. The total cost to the consumer is estimated at $8.4 billion a year because producing the required corn feedstock increases corn prices. One estimate is that ethanol production adds more than $1 billion to the cost of beef production [3]. Last year, a $1 per gallon government rebate on biodiesel went into effect. The US livestock producers are likely to see even higher prices for smaller available supplies of grain for feed [9]. Currently 11 percent of the US corn crop goes to produce ethanol, and 15 percent is exported to livestock producers as far away as Japan and South Korea. The grain operator ADM will construct its first wholly owned US biodiesel facility in North Dakota to take full advantage of the multiple subsidies, which will make things worse for farmers, consumers and the environment without providing a real solution to climate change and the energy crisis.

So what’s the real solution?

Plenty of solutions

There are many solutions in renewable energies that are truly sustainable, as described in our ISIS Energy Report.

Solar power, for example, is getting cheaper, more versatile and more efficient everyday. The world’s energy needs can be satisfied with solar panels at even a low 10 percent efficiency covering just 0.1 percent of the earth’s surface. They can be incorporated into existing building structures and are ideal for local micro-generation [10].

I want to concentrate on energy from biological wastes, which has enormous potentials not only in terms of energy that can be harvested, but also in reducing carbon emissions. But not I hasten to add, not incineration, which is also what the Blair government is supporting [11].

First and foremost is anaerobic digestion to harvest biogas, which is 60 percent or more methane that can be used the same way as natural gas.

Anaerobic digestion of biological wastes for a renewable and carbon mitigating fuel

There are numerous advantages of anaerobic digestion, which has the potential to provide 11.7 percent of all energy needs, or 50.2 percent of transport fuels in the UK. Methane can be used both as fuel for mobile vehicles or for stationary combined heat and power generation.

Methane-driven vehicles are already in the market, and they are the cleanest vehicles on the road by far, ranking top green cars of the year in 2005 [12]. Sweden has thousands of them, supported by hundreds of filling stations; many operated from locally produced biogas.

Biogas methane is a renewable and carbon mitigating fuel; it is more than carbon neutral. It saves on carbon emission twice over, by preventing the escape of greenhouse gases methane and nitrous oxide into the atmosphere and by substituting for fossil fuel.

Anaerobic digestion conserves plant nutrients such as nitrogen and phosphorous for soil productivity. In fact, many third world countries started to use anaerobic digestion for making good fertilisers before they began to use the methane for energy.

Anaerobic digestion prevents pollution of ground water, soil and air with nitrates, methane, nitrous oxides, and other contaminants. It improves food and farm hygiene, and has been shown to destroy disease bacteria. It can be adapted to produce hydrogen either directly or from methane. And if and when research and development in hydrogen storage and fuel cells become further advanced, anaerobic digestion can link up quite easily.

There’s a company, Organic Power Ltd, run by Chris Maltin in Somerset here in Britain, which produces its own biogas methane to run methane-powered Mercedes people carriers (“Organic waste-powered cars”, SiS 30).

Anaerobic digestion of biological wastes can provide 11.7 percent of UK’s energy needs and saves at least 15.8 percent of carbon emissions

Here are the calculations showing how UK’s biological wastes can potentially provide more than half (50.3 percent) of transport fuel and 11.7 percent of all energy consumed in the country.

UK produces 434 Mt of solid wastes a year, of which 25.5 Mt of municipal solid wastes and 62.143 Mt of commercial and industrial wastes are organic and suitable for anaerobic digestion. These numbers are extracted from a report written for the Office of National Statistics published in January 2005 [13]. From FAO statistics [14], I gathered that UK’s total agricultural production in 2005 was 41.6915 Mt, counting cereals, fruits, pulses, vegetables, oilseed rape, sugar beet, potatoes, and mushrooms. Assuming that waste constitutes fifty percent of the harvest, i.e., 41.6915 Mt, the total amount of biological waste that can be treated in anaerobic digesters is 129.3345 Mt. This includes high-yielding feedstock such as fats and grease, bakery wastes, food scraps, grass silage, green clippings and brewery wastes, producing 961 to 120 cubic metres of methane per tonne [15].

In addition, there were 11.887 million cows, 43.851 million sheep, 7.719 million pigs and 128.261 million poultry in the UK in 2005 [16], producing 208.685 Mt of livestock manure, according to estimates of per capita livestock manure production given by the report from the Office of National Statistics [13]. The different manures yield 25 to 80 cubic metres methane per tonne [15].

Taking a conservative average of 200 cubic metres for the organic wastes and 30 for the livestock manure, we get enough to produce 1 285 PJ (1015J) of methane energy per year. The total energy consumed in the UK in 2005 was 10670 PJ, or which 3643 PJ were transport fuels [17]. Thus, methane from wastes can potentially supply 11.7 percent of UK’s total energy requirement, or 50.3 percent of transport fuels. This is quite remarkable.

The carbon emissions saved is even more astonishing. The total volume of methane potentially available from biological wastes each year is 32 070 million cubic metres. Assuming a global warming potential of 22, this is equivalent to 508.0 Mt of carbon dioxide, which comes to a whopping 90.6 percent of the national emissions of 561 Mt [16]! The same amount of methane substituting for fossil fuels save 88.8 Mt, a more realistic 15.8 percent of the national carbon dioxide emissions. These figures suggest to me that we have seriously underestimated the greenhouse gases emitted by the mountains of biological wastes in this country, indeed in any country that go into landfills; and that methane mitigation will contribute an extraordinary amount to reducing actual greenhouse gases in the atmosphere.

Green algae for carbon capture and sustainable biodiesel 

A league table compiled by the Guardian newspaper showed that the five biggest polluters in the UK are all power stations, and together produced more carbon dioxide than all the country’s motorists [18]. EON UK, the electricity generator that owns Powergen, UK’s top, emitted 26.4 Mt carbon dioxide in 2005, slightly more than Croatia.

 The five (EON UK, RWE Npower, Drax, Corus and EDF) together produced over 100 Mt, while the country’s 26 million motorcars produce 91 Mt.

Another big solution considered by the UK government is CCS, carbon capture and storage. It is a process literally to capture the carbon dioxide from the exhaust of big power stations and store it deep underground. This method is clumsy and uneconomical, and even the US Department of Energy appears not to favour it [19]. So what is the real alternative?

Green algae actually don’t mind growing in the exhaust gas from power generation (“Green algae for carbon capture & biodisel”, SiS 30).

A suitable species can mop up 40 percent of the carbon dioxide, and 86 percent of nitrous oxide when bolted to the exhaust, where it grows prolifically. Some species can yield up to 50 percent oil by weight, and you can get up to 15 000 gallons of biodiesel an acre a year, as opposed to 60 gallons from an acre of soybean.

Putting all the appropriate technologies together

How can we put all these technologies together to be food and fuel secure or even food and fuel rich? Just as we cannot depend on imported energy, we may not be able to depend on imported food. All the predictions are that global warming will impact negatively on food production, particularly as water is also depleted as well as oil, and conventional industrial agriculture is addicted to both of them [20] (“Sustainable food system for sustainable developmentSiS 27).

To make things worse, our globalised food trade uses up a lot of energy and spews extra mega tonnes of carbon emissions into the atmosphere.

The social, environmental, and economic costs of food transport in the United Kingdom estimated in a report commissioned by DEFRA amounted to £9 billion a year, or 34 percent of the total value of the food sector [21] ("Food miles and sustainability"). There is every reason to be self-sufficient in food and to consume food produced locally. It is healthier, more nutritious and saves on energy and carbon emissions.

The same goes for energy. Energy use at the point of production saves 69 percent on efficiency alone, as the ‘waste’ heat can be used in combined heat and power generation, and also avoids the average 7.4 percent loss incurred in long distance transfer of electricity through the grid [22].

Dream Farm I for energy and food self-sufficiency

Things all come together in Prof. George Chan’s idea of integrated food and waste management system, which I have described as [23] (“Dream farms”, SiS 27), “abundantly productive farms with zero input and zero emission powered by waste-gobbling bugs and human ingenuity.” We are very fortunate to have Prof. George here to say a few words to us ( “Complete recycling of all resources for sustainability”, this series).

In George’s farm, which I call Dream Farm I, the anaerobic digester is the key technology. You can have two, three or more in series or in parallel. The anaerobic takes in livestock manure plus wastewater, and the naturally occurring bacteria in the manure ferment the wastes and generate biogas, which provides all the energy needs for heating, cooking and electricity. The partially cleansed wastewater goes into the aerobic digester, shallow basins where green algae produce by photosynthesis all the oxygen needed to detoxify the water, making it safe before it goes into fishponds. The algae are harvested to feed chickens, ducks, geese and other livestock. The fishponds support a compatible mixture of 5-6 fish species. Water from the fishponds is used to ‘fertigate’ crops growing in the fields or on the raised dykes. Aquaculture of rice, fruits, vegetables and flowers can be done in floats on the surface of the fishpond, saving backbreaking work involved in weeding and watering. Water from the fishponds can also be pumped into greenhouses to support aquaculture of fruits and vegetables, where the remaining nutrients are removed, and the water polished clean to return to the aquifers. The anaerobic digester yields a residue rich in nutrients that is an excellent fertiliser for crops. It could also be mixed with algae and crop residues for culturing mushrooms after steam sterilisation. The residue from mushroom culture can be fed to livestock or composted. Crop residues are fed back to livestock. Crop and food residues are used to grow earthworms to feed fish and fowl. Compost and worm castings go to condition the soil. Livestock manure goes back into the anaerobic digester, thus closing the grand cycle. The result is a highly productive farm that’s more than self-sufficient in food and energy, and saves substantially on carbon emissions.

George’s farms make happy animals. They are organically fed and toilet-trained to deposit their manure into a sump that goes to the digester, so the animals and their housing are spotlessly clean.

Another aspect worth stressing, especially in times of water shortage and floods is that the fishponds in Dream Farm I are great for water management, it provides water conservation, purification and flood control. As the dykes are raised above the surrounding levels from the mud dug up, they can accommodate much more water without overflowing in times of heavy rain, and provide an effective reservoir in times of scarcity. Aquaculture on the surface of the pond also helps reduce evaporation losses.

Dream Farm II

Based on Dream Farm I, we have proposed to set up a Dream Farm II  [24] for education/demonstration and research purposes (“Dream Farm II, how to beat climate change and post-fossil fuel economy”, SiS29), to act as incubator for new technologies, new designs and ideas, and as information exchange to support real farms like this springing up all over our countryside and all over the world. Such farms can supply nearby schools, old peoples’ homes, towns and cities with fresh healthy foods all year round, reducing their enormous ecological footprints immeasurably, and also contribute to revitalising the rural economy.

The additional elements are all forms of renewable energies suitable for local energy generation at the medium, small to micro-scale. Solar panels, wind turbines, suitably scaled down and improved for aesthetic design. The farmed livestock, fish and crops will be based on indigenous species and local varieties as much as possible, providing an opportunity for Britain to recover its rich heritage of natural and agricultural biodiversity that has been decimated by decades of industrial agriculture. It would enhance the local cuisine and restore healthy diets to the nation. Jimmie Oliver would be ecstatic about this farm, which could support an on-site gourmet restaurant as well as an analytical laboratory.

Our approach is to get the farm up and running on core technologies while newer technologies are integrated or substituted at the periphery as time goes on, including hydrogen technologies, and carbon capture using algae by passing the exhaust from the combined heat and power generator through the algae culture, and turning the algae into biodiesel.

The possibilities are endless. Giving up fossil fuel not only gives us a greener and healthier planet, it will unleash all the bottled up creativity and energies that work for people and planet.

Dream Farm and the new paradigm

Dream Farm is also a concrete demonstration of a new paradigm at work.

The important features of zero-emission, zero-waste systems are the same as the ‘zero-entropy’ model of organisms and sustainable systems I first proposed in 1998 in my book, The Rainbow and the Worm, the Physics of Organisms.

The zero-entropy model predicts balanced development and growth as opposed to the dominant economic model of infinite, unsustainable growth. The alternative to the dominant model is definitely not an end to growth, as too many critics are advocating.

Instead, the key to how organisms survive and thrive is the same as what makes a system sustainable. It involves maximising reciprocal, cooperative and synergetic relationships rather than the competitive; it is to use the output of each cycle to feed another, and closing the big cycle in a balanced way. In the context of the farm, it is to turn ‘wastes’ into resources.

In the dominant model, the system grows relentlessly, swallowing up the earth’s resources without end, laying waste to everything in its path, like a hurricane. There is no closed cycle to hold resources within, to build up stable organised social or ecological structures.

By contrast, the archetype of a sustainable system is a closed lifecycle, it is ready to grow and develop, to build up structures and perpetuate them, and that’s what sustainability is all about. Closing the cycle creates a stable, autonomous structure that maintains itself and renews itself. In other words, it is self-sufficient.

The cycle contains more cycles within that help one another thrive and flourish, as in the minimum integrated farm, with farmer, livestock and crops. It can perpetuate itself as such, or it can grow by incorporating more life-cycles, more crops, more productivity, more farm workers, more jobs. The carrying capacity of a piece of land is by no means a constant. It can be ten times more productive, depending on how it is organised.

That is why productivity and biodiversity always go together. Industrial monoculture, by contrast, is the least energy efficient in terms of output per unit of input, and less productive in absolute terms despite high external inputs, as documented in recent academic research. Biodiversity is nature’s way of maximising the reciprocal, symbiotic relationship that sustain all and make the whole ecosystem thrive. That is the lesson we need to embrace for a paradigm shift to the wonderful life without fossil fuels.

This article is based on her presentation in the Which Energy? Launch Conference, House of Commons, 25 May 2006, London, UK

Article first published 27/06/06


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