The Centre for Alternative Technology has produced a major new report setting out how Britain can respond to the challenges of climate change, resource depletion and global inequity.
It examines how the UK can meet its electricity and heating requirements through efficient service provision, while still decreasing emissions. It argues that making the necessary transition to a low-carbon future would not only stimulate the economy and create employment, but would also provide greater security, freedom and an enriched quality of life. The report is divided into five sections: Context; PowerDown; Land Use and Agriculture; PowerUp; and Framework.
Here's a summary for the agriculture and land use sector.
Scene setting facts: Great Britain is made up of about 11.2 million hectares of grassland, mainly used for grazing livestock; about 4.87 million hectares of arable crops, of which 2.1 million are used for growing livestock feed; 3.24 million hectares of woodland; and 3.28 million hectares of urban land. Greenhouse gas emissions from the land use and agriculture sector are made up of nitrous oxide, methane and carbon dioxide.
Trade context underlying scenario construction: the authors assume that 15% of our food needs will be imported from the EU, and about 7.5% from the tropics, but apart from this our food needs must be met domestically. Agricultural energy use: this is assumed to be decarbonised - this is dealt with in other chapters. The effect is to reduce the greenhouse gas intensities of land use products by approximately 20% for livestock and about 45% for crops.
Basic strategy: the main approach taken is to reduce consumption of high GHG/land take foods and to use the land released for biomass in order to sequester carbon and provide a source of energy.
Outputs from scenario
Food for consumption: The report stresses that there will be plenty of food but that the type of food consumed will be different. Livestock products are substantially reduced. The main reduction will be in cow and sheep products – beef will be 10% of today’s levels, and dairy cows and sheep both 20%. The levels of egg, poultry and pig-meat production are only a little lower than today because they use little land and will be fed on high-yielding crop products and food wastes. Eggs are 100% of today, pig meat 80% of today and poultry 50%. On welfare it says: “We do not specify how these would be reared, but for animal welfare reasons it is supposed that a larger proportion than today would be low input, “free-range” and/or organic, many in small operations serving local markets. There might well be novel and productive ways of combining livestock with woodlands and the “new” perennial crops.” There is also a five fold increase in farmed fish fed on grains. The feed industry will be smaller than today and there will be no soy imports – indigenous production of oilcrops and legumes will be increased. Consumption of plant protein is greatly increased; at the moment the ratio of meat to plant protein is about 55:45, and in the scenario it is to 34:66. The report says that this proportion of livestock products matches recommendations for optimum dietary health as set out by the Harvard School of Public Health (referenced in the report).
Non food outputs: After food needs have been met, 43% of the remaining “productive non-food” land is dedicated to growing biomass for carbon sequestration. Carbon is also sequestered in soils through best practice management, encouraged though financial incentives. Over 70 million tonnes of biomass for energy is produced. This is used in the following ways: 16 million tonnes for biogas (bio-synthetic gas), mainly used to back up the electricity grid; 18 million tonnes of woody biomass for CHP; and 27 million tonnes to create kerosene, petrol and diesel using the Fischer-Tropsch process to power those parts of the transport sector for which there is currently no alternative to liquid fuels. The report points out that soils cannot sequester carbon indefinitely and say that after equilibrium is reached (in about 20-30 years) other methods of sequestering carbon may be possible including deeper soil sequestration or new technologies.
In terms of making this scenario work, the report does have a separate chapter on behaviour change and in a sense the report assumes that circumstances will become so severe that change will have to happen. It also assumes that carbon pricing will shape purchasing and production emissions. It says this: “If carbon prices in the 2020s are above £200 a tonne and rising, this will strongly favour low-intensity products and penalise high-intensity ones. To give a crude example, a price of £400/tonne would amount to a penalty of around £4800 per tonne of beef, negating all but the highest added value.Meanwhile the three hectares that produced this tonne of beef could be producing, say, 50 tonnes of sequestration crops, worth up to £20,000 in carbon credits. It is unlikely to be so brutally simple in practice, but the example shows how carbon pricing could invert the present order of things and drive completely different choices for farmers. At the same time, consumers too would be reorienting their food choices in response to unmistakable price signals.”
The report concludes as follows: “A healthy diet is provided for the population on only 29% of the land currently used for food production, supplemented by low-carbon imports. It provides a much higher degree of food security than at present. Total greenhouse gas emissions from agriculture are reduced to a fifth of their current quantity, leaving a total of 17 million tonnes of CO2e. Meanwhile the sector provides enough biomass to fulfill the fuel needs of the other sectors and to sequester carbon at a rate of 67 million tonnes of CO2e year. These “negative emissions” match the residual emissions from other sectors to meet the scenario’s ultimate goal, of a zero carbon Britain.”
Some features are similar to the recent Wales report that came out (see below) in terms of the emphasis it gives to biomass production but it has a very different take on the amount of livestock products we eat and how those animals are reared.
For more about the Centre for Alternative Technology see here.
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