Category Archives: Food & Farming

Greenhouses

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Seawater Greenhouse's Somaliland Project

Seawater Greenhouse’s Somaliland Project: super productive fruit and vegetable production, where it is needed most

In blogs over the last couple of weeks I’ve looked briefly at the unsustainability of current systems of farming. As the global population continues to rise there are many predictions of further food shortages and yet more ecological damage. I remain convinced that we could feed 9 billion or more people and simultaneously restore biodiversity. To do so will require changes to systems of grants, subsidies and economic justice, which I’ll cover in a future blog. Greenhouses, and other systems of protected cropping, seem to me to be the most important technological change.

I grow a huge range of fruit and vegetables in my two small unheated greenhouses and little polytunnel, all in an urban back garden. We have plenty of organic fresh green salad crops to feed family, friends and neighbours every day of the year. For six months of the year we have an abundance of tomatoes. However it is at the bigger scale that the real possibilities open out.

Thanet Earth is the largest greenhouse complex in the UK. Inside each of their five huge greenhouses is a gas combined heat and power plant, utilizing the heat and Co2 within the greenhouses and selling electricity to the grid at times of peak demand. In Australia Nectar Farms have recently built a 40 hectare greenhouse project, linked to a local wind farm and battery storage system, to provide heat and light for greater year round cropping. Sundrop Farms Port Augusta project uses concentrating solar power to provide desalinated water as well as heat and electricity for their innovative desert based farming system. They, like Thanet Earth, Nectar Farms and many modern greenhouses can control temperatures very precisely, so ideal growing conditions can be maintained year round. They grow hydroponically, and use light, as well as heating and cooling, to maintain year round cropping. Yields per acre are huge.

Plenty Farms in California are expanding rapidly as Silicon Valley billionaires are pouring money into this new start up, which is organically growing leafy green vegetables under a system of vertical hydroponics and relying just on LEDs for light. Around the world others too are growing crops in old shipping containers, factories and warehouses, often in inner city areas, close to where the people are.

I’ve blogged before about solar desalination and mentioned pioneering projects in Australia, Jordan and Qatar. The team at Seawater Greenhouse have just completed construction of their project in Somaliland, which uses cheap shade netting and evaporative walls to create cool moist conditions in the hot dry desert. This is a tiny project yet it shows one possible way to rapidly and sustainably increase food production. It could be hugely significant in the future. Christopher Rothera’s blog and photos really give a good sense of this project.

Another system that I’m passionate about is aquaponics; I blogged about this in 2011 (here and here). Kate Humble and her team, together with Aquaponics UK have built a great system near Monmouth. Again it is a tiny project that could well be a prototype for much larger systems. They’ve some great videos on their website.

In this blog I’ve mentioned some very diverse types of greenhouses and related technologies. The one thing they all have in common is that they produce a lot of food in a limited area and do it in ways that are energy efficient and, to varying degrees, ecologically sustainable: just what we need to feed nine billion people.

Arable Farming & Ethical Eating

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Maize, like other grain crops, is usually grown in unsustainable ways

Maize, like other grain crops, is usually grown in unsustainable ways

Last week I wrote about meat and whether it can be part of a diet that is ecologically sustainable. Today I want to look at the alternatives. The ethical complexities are many, and are one reason why I’ve never been a vegetarian, let alone a vegan. Take the choice between whether it is more ethical to eat Welsh lamb or Egyptian new potatoes. I decided many years ago that on purely ethical grounds the spuds had the greater negative impacts. When poor countries such as Egypt export relatively low value food items like potatoes, which require a lot of water and land, it pushes up the price, and Egypt’s urban poor are forced into ever greater food insecurity. Growing for export favours the bigger produces and pushes small farmers growing for the local market out of business, and thus land ownership becomes more concentrated. There are also of course the environmental impacts of growing the crop in a water stressed country like Egypt, and the pollution and carbon emissions of such long distance trade.

Most of the world’s arable farming is now dependent on a range of fertilizers, herbicides, pesticides, fungicides and systems of ploughing that are destroying the soil and its complex microfauna. Bees, butterflies and the broad range of insect species seem to be in global decline. As the smaller and simpler life forms die off so to do the birds and mammals that feed upon them, all the way up to the iconic apex predators. These systems of farming have been responsible for a decline in organic carbon content of soil, typically from say 5% to 0.5%, which is very serious from both climate change and food security points of view. In most cases the use of genetically modified crops is only exacerbating the damage for a very small increase in global food production.

Traditionally environmentalists have argued the case for small scale, mixed, organic farming, or systems of permaculture. Such farming practices are certainly very much more ecologically sustainable, but either tend to produce less food per acre, or to require more labour. They also have not had the political support, and therefore grant subsidies, that more ecologically damaging systems of farming have had. I would certainly like to see more support for these sectors.

One area of food production that is expanding, and where huge increases in productivity per acre can be achieved in ways that are potentially very ecologically sustainable is greenhouses, polytunnels and other forms of protected cultivation. This is not to say that all such systems are ecologically sustainable, but some are. On the very small scale I have two small greenhouses and a little polytunnel in our back garden from which I harvest a huge diversity of fruit and vegetables all year round. The productivity per acre is extraordinary. However it is time consuming and the old green idea of the self provisioning economy has singularly failed to take off in this world of busy, time-poor, modern urban living.

In the next week or so I’ll write about a few of my favourite farms that are developing highly productive systems of greenhouse cultivation that show we could feed a very much larger global population with a predominantly vegan diet on a relatively small area. This could leave a considerable area of land for rewilding and for some pasture fed meat and dairy farming.

Meat

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Can eating meat be ecologically sustainable?

Can eating meat be ecologically sustainable?

Meat is a complex and controversial issue. Can it be part of a diet that is ecologically sustainable and socially just? Arguments rage about this issue. One of the complexities is that meat is produced in very variable ways. The very best systems of pasture management can, it is argued, sequester more carbon into the soil than is necessary to offset the methane the cattle produce. They can also be part of restoring biodiverse habitats. In a blog in June I sang the praises of Will Harris of White Oak Pastures. However this represents the very apex of good meat production. The vast majority of meat production is very much less sustainable. Most animals raised for human consumption are fed on grain and soya that would be much more beneficially eaten directly by people. Even the best systems of meat production use a lot of space per unit of food produced. It would certainly be a good thing if humanity could massively reduce its meat consumption, say by 80 or 90%.

One of the common assumptions people writing about population and diets was that as people get richer they would eat more meat. Throughout the Twentieth Century this held true: not any more. Veganism is growing rapidly in many countries, and it seems especially so among the young and better educated. Also for many of us who are omnivores we are eating a lot more meals that are plant based, with a very much reduced intake of meat and dairy.

Globally levels of meat consumption vary a lot. Argentina and Uruguay top the table of per capita meat eating. India and China traditionally ate very much less but as people are getting wealthier they are eating more. Total global meat consumption is still rising but this may not go on much longer if veganism, vegetarianism and low meat lifestyles become more common, as I think they probably will.

If humanity could reduce its meat consumption dramatically, (say by 80%) that would free up an enormous area of land for other purposes. Some of this could be used for agroforestry or renewable energy projects, but the vast majority could be used for rewilding. Increasing the area of forests in the world could help restore habitats thus allowing biodiversity to flourish again, and it would be a very effective way of sequestering carbon, so vital in helping combat climate change.

Some people think that cultured meat, grown in laboratories, will replace traditional meat eating. Others see vegetable based meat substitutes, like textured soya protein as having a major role. Some argue we should switch from traditional meats to insects. Maybe meat eating will simply decline without the need for ersatz meats. Any of these perspectives may prove to be true. It is too early to say.