This is a modified version of an essay originally submitted to crossroadsforsociety.org by Ken Whitehead on Jan 12 2013
In part one of this essay I looked at how the industrial agriculture system is unlikely to be able to supply the food needs of the Earth’s population for many more years. I believe that the future of agriculture will evolve based on three potential future energy scenarios. The first is business as usual, where we continue burning fossil fuels indiscriminately and follow the vision of endless economic growth to its inevitable end. This is the path which is likely to lead to the scenario of a global food crisis described in part one. With the current focus of agribusiness and governments around the world, this policy is unlikely to change until its negative effects really start to bite. By then it will most likely be too late to prevent serious food shortages from occurring. The hope must be that these will be short term, as society changes its focus to more sustainable forms of agriculture and sources of food.
The second option is that we move to a more energy-efficient model for agriculture, based mainly on renewable sources of energy. This option will require top-down changes to the way agriculture is organised, which will necessitate a transition to lower-energy technologies, and a reduction in net energy consumption from present-day levels. While this option will be difficult to implement and is likely to encounter considerable resistance, I believe that with our current available technologies we have no choice but to move in this direction. The main implication of the low energy scenario is that the industrial model of farming would no longer be practical for many areas. We could no longer keep vast fleets of tractors, combine-harvesters, and energy-intensive farm machinery running in an environment without fossil fuels. So what are the alternatives?
One option is organic farming, which has seen considerable growth over the last few years. In term of food grown per unit area it is considerably more efficient than industrial farming. However organic farming is very labour intensive, and to carry it out on a large scale would require considerably more human involvement in the food-production cycle than there is at present. This may be no bad thing for society, as people once again establish a connection with the land which has largely been lost in our current society. Organic food is often viewed as an expensive luxury in today’s world. If we were to adopt these techniques on a large scale organic farms would need to start growing staple crops aimed at providing the greater part of people’s diet, rather than simply producing exotic boutique-style foods, as happens all too often at present.
Hydroponics and Aquaponics
Another option is hydroponics. Currently this technique is used for high value crops, but it can be applied to almost any plant, other than root vegetables. Instead of being planted in soil, plants are immersed in a special growth medium and water containing dissolved nutrients is circulated around the roots. This is a very efficient way of growing vegetables and can increase crop yields considerably. Since it is continuously recycled, only a twentieth of the water is required, compared to conventional farming. Also since the crops are grown indoors, it is possible to avoid the use of pesticides entirely, and grow what are in effect organic vegetables. To further increase yields, artificial lighting may be used. However this uses a considerable amount of electricity and is unlikely to be a viable option in a future low-energy society, even with new highly-efficient LED lights. Hydroponics is currently expensive, since there is a large investment required to build the glasshouses required. For that reason, the focus to date has been on high-value crops, such as vegetables. However there is no reason in principle why this technique could not be used to grow staples such as rice or grains if the economic conditions were favourable.
A variation on hydroponics is a technique known as aquaponics. In an aquaponic system vegetables are grown hydroponically, but with the addition of a pond or tank in which fish are raised. These fish are typically non-carnivorous species such as tilapia, which can live on a diet of pond weed, or another readily-available source of food. The waste produced from the fish can then be used to provide nutrients for the vegetable crop, and a part of the vegetable crop can provide additional food for the fish. Aquaponics is therefore a very efficient way of providing both vegetable products and fish for human consumption. Aquaponic systems are also scalable, and a small system can provide almost all the nutritional needs for a family. Such systems therefore have tremendous potential in the third world, in areas where conventional food and water resources are scarce.
Algae as Food
In order to be able to feed a population of nine or ten billion with less energy than we currently consume, we will also need to look at developing new sources of food. Algae have been the focus of much research of late, mainly because of their potential to use as a stock for producing biofuels. However it may be more productive to use algae as a source of food, either directly for human consumption, or indirectly as a source of animal feed.
The most familiar form of algae to many people is seaweed. Species such as kelp, which grow in coastal waters, are some of the fastest-growing organisms on the planet, and can grow at rates exceeding half a meter per day. Seaweed is nutritious, and could potentially form a significant part of the human diet. In Japan for example, seaweed provided ten percent of the total food consumed prior to the 1970s. Kelp is abundant, easily harvested, and could easily be adapted for farming. It is also ideal as a stock food for aquaculture, and for land-based farming operations. Seaweed is currently sold as a speciality product for seasoning foods, as well as for many non-food applications. Once again, the challenge is to move beyond the perception of seaweed as a boutique-type product, and start thinking in terms of making it a significant part of our future diet.
Sources of Protein
Another option which has been little exploited to date is the use of insects as a food, otherwise known as entomophagy. Indigenous populations have made use of this resource for many years in Australia and in parts of Southern Africa. However in many first-world societies there is a cultural taboo against eating of insects. As food from conventional sources becomes scarcer however, this option is becoming increasingly attractive. Insects are nutritious, fast growing, and ten times more efficient at converting input food to edible body mass than beef cattle. They also offer considerable advantages over conventional farming in terms of the space requirements and turn-around time, with daily weight increases of between four and twenty percent. The most suitable species, such as locusts and cockroaches have a meat-like texture when cooked and apparently “taste like chicken”. Entomophagy could potentially meet nearly all of the human population’s protein needs, if cultural taboos could be overcome. It also has the considerable advantage that spoiled or wasted food can be used as a feedstock, thus helping to reduce overall food wastage.
There is also a need to provide more efficient sources of conventional protein to meet the demands of the human population. Currently the most efficient common protein source is poultry, which uses a fraction of the input resources required to produce an equivalent weight of beef. When egg production is factored in, poultry production looks like a good bet for the future. However there are a number of ethical concerns surrounding battery farming of chickens, and it is likely that in the future, poultry would be required to be farmed in a more humane manner.
A new possibility is the use of iguana as a source of protein. A number of trial projects are currently underway across central America, with villagers raising iguanas for human consumption on a small forest plots. Since iguanas are cold blooded, the amount of body mass produced relative to the food they require is very high. Also since they are indigenous to the area, less food is required, and much of the required food can be provided from the forest. This kind of project also has the positive side effect that it encourages forest restoration, rather than deforestation.
One other potential source of protein is that derived from aquaculture. This term is fairly wide ranging and can be used to refer to anything grown in an aquatic environment, from algae to fish. We have already discussed farming of seaweed, so I will confine this discussion to other marine organisms. Shellfish such as muscles and oysters have been farmed for many years around the world. They are generally raised in specialised facilities, often located in coastal inlets. These operations are generally sustainable, and do not require the input of large amounts of additional resources. There is scope to increase production well above current levels, but it is unlikely that shellfish could provide a large proportion of the future protein requirements for humanity.
Fish farming has the capability to provide large amounts of available protein if it is properly organised. The current boom in open-net salmon farming is environmentally unsustainable, since it requires three to four times as much wild fish to produce an equivalent weight of farmed salmon. Open-net fish farms also can cause contamination of the wild salmon stocks through transmission of pathogens such as sea lice. Much more promising are closed-containment fish-farming systems, using non-carnivorous species such as perch and tilapia. These fish, while small, breed prolifically and grow quickly. They are very resilient and can survive in a variety of different environments. In many parts of Asia, perch are farmed in flooded rice paddies, in effect forming a closed system where the waste from the fish feeds the rice plants and the rice plants provide food for the fish.
Genetically Modified Crops
One development which could have a profound effect on the food supply in the future is the development of Genetically-Modified (GM) crop strains. This practice is already widespread across North America, where most of the food consumed is genetically modified. In Europe there has been considerable resistance to GM crops, and as a result the majority of food is still derived from non-GM strains. While GM crops may have considerable potential, most of the modifications created so far appear designed to increase corporate profits, rather than to boost crop yields. Examples include crop strains which are modified to increase resistance to herbicides. It is obvious that the objective of this is to increase sales of herbicides, thus adding yet more chemicals to the foods we are forced to buy.
This is the exact opposite of the type of sustainable-farming practices we need to adopt if we are to feed the world’s population. That being said, if GM crops can be shown to be safe and to improve yields, then they may be a necessary part of our future food strategy. However there is also the danger of cross-pollination, which could render healthy wild strains vulnerable to new pathogens, ultimately threatening the genetic diversity of many crop staples. We have already let the genie out of the bottle with GM crops, so whether they are a good thing or not, we will likely have to deal with them in any future food scenarios.
Mention artificial meat to most people and you will probably get blank stares. Yet this is potentially one of the most exciting areas of research in the food industry. Researchers in both the US and Holland are on the verge of producing synthetic meat substitutes, which could revolutionise the food industry over the next few years. There are two different approaches, with the development of plant-based meat substitutes being pioneered by researchers from Stanford University. This approach starts with plant materials and passes them through a proprietary process to produce a final product with a meat-like texture. While this sounds little different from past attempts at producing meat substitutes, which have resulted in such gastronomic delights as the vegi-burger, the final product is apparently almost indistinguishable from real meat. While such a process could theoretically revolutionise the food industry, the main priority needs to be to feed the world’s population, and there have to be concerns over “proprietary” processes which could potentially limit the potential of this such products in poorer countries.
The Dutch approach is to create genuine synthetic muscle tissue artificially from stem cells. By using this approach, small clusters of synthetic muscle fibre can be grown, which can then be amalgamated to produce edible synthetic meat. Although this technique is not yet able to produce synthetic meat in large quantities, there is no reason in principle why this would not be possible. The vision is to have incubators spread around the world, which could produce sufficient artificial meat to make it available to all the world’s population at a very low price. Producing artificial steaks is still a long way off at this stage, since the researchers need to work out ways of stressing muscle tissue and providing scaffolds around which it can grow. However it should be possible to produce the equivalent of ground beef within a few years, with very little environmental impact, since artificial meat requires a small fraction of the nutrients it takes to produce real beef or pork. There is no reason why this process should be limited to beef. All kinds of meat and fish tissues can be created using this process, making it theoretically possible to produce a diverse range of synthetic animal protein sufficient to meet all human needs.
So far I have discussed possible future trends for agriculture under a business as usual scenario, and also under a scenario where energy is produced mainly from renewable sources and is therefore in limited supply. The third possibility is that of a future where energy is available in abundance. This could potentially come about through the development of nuclear fusion as a power source. In particular, I believe that small-scale plasma-focus fusion is one largely overlooked technology which has considerable potential to move us into a world of cheap abundant energy. While the concept has yet to demonstrate net energy output, there is considerable evidence that such a process is both theoretically possible and physically achievable. This is in marked contrast to the unsubstantiated claims made for LENR or cold fusion, which have given all forms of alternative nuclear fusion a bad name.
With plentiful supplies of cheap energy available, large-scale desalination of ocean water would become a realistic option. Anywhere close to the coast could therefore have access to abundant supplies of fresh water. The costs of pumping water long distances would also be low, making it possible to irrigate large tracts of barren land, and potentially develop new croplands in desert areas.
Moving Agriculture Indoors
More exciting still is that cheap and abundant energy may make large-scale vertical farming a practical option. Instead of requiring thousands of hectares of land to grow staple crops, the same amount of food could be produced from a multi-story urban farm, with crops being grown hydroponically under artificial lighting. Such a farm, covering an area of a square kilometre, could provide sufficient food to meet most of the needs of a medium-sized city. The vertical farm concept is completely scalable, and it is possible to imagine a scenario where each town and village would have its own vertical farm, which would be able to grow most of the food its inhabitants needed.
Because the growing of food would occur in an indoor environment, no herbicides or pesticides would be required, and growing conditions would be totally controlled, thus freeing crop production from the vagaries of the weather and any of the negative impacts we can expect from climate change. The concept of vertical farming also lends itself to the idea of co-operatives, which would make it possible for communities worldwide to be able to feed themselves, without having to worry about the costs incurred. Vertical farms could easily form the basis of local food production centres, with crop cultivation, artificial meat production, and aquaculture all occurring under the same roof.
This last option may represent the long-term future of food production. If this model were to take hold worldwide it would theoretically be possible feed every person on this planet a varied and nutritious diet. Most current agricultural land could be taken out of production, permitting much of the Earth to be rewilded, and allowing it to recover from centuries of human-inflicted damage. Freed from worries about food availability people could potentially live longer, healthier, and more productive lives.
Whatever happens, business as usual is not a sustainable option for the future. At present we need to focus on developing low energy options for growing food, as it is by no means certain that a future based on energy abundance is even possible. However it is encouraging that solutions do exist which, on paper at least, would allow all people on the planet to receive sufficient food, as long as human populations have ceased growing by the end of the century. In a world of energy abundance there will be a greater range of choices for food production, but even in a world of energy scarcity it should be possible to avoid a Malthusian collapse of the food supply.