Posts Tagged ‘energy’

Energy in agriculture.

December 16, 2008

 

The background is a Swedish book (Svart jord (Black Earth) by Gunnar Lindstedt.

 

It is interesting and almost thrilling. The development of agroprojects in Russia, the development in USA, organic farming in Sweden is followed. Focus is on people involved. Is large scale Agrobusiness the way forward for the planet? What happens to the countryside, the soils. the environment, the entire society? Important questions are put forward.

 

There is an undertitle: Can agriculture deliver our daily bread when the oil is scarce? In the text some odd figures are given on energy use in the food chain, fertilizers in agriculture etc. But the result is misinformation. Most reviewers in the press have learnt that agriculture uses 10 times more energy than it produces, and a major culprit is fertilizers.

 

The energy relations (excluding the sunlight) in the Swedish food chain are as follows (relation output of energy/input):

Crop production: 4-9  (output 4-9 times the input as fertilizers, fuel, machinery etc)

Crop + animal production (=agriculture): about 1.5

Agriculture+food industry+logistics and trade+consumers purchase and cooking: 0.2

Considering waste and losses in the latter activities a final figure might be 0.1

 

There is ground for critizising the efficiency of the food chain, but why see the only efficient activity, the crop production, as the culprit?

 

Misinformation like this disturbs serious work on the problems ahead of us: increased population, ongoing urbanization, increasing environmental pressure, Agrobusiness given advantage compared to local production.

 

 

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Our energy future.

November 4, 2008

 

Do we take the energy issue seriously? At least, I have much more background and really a kick from a report: Energy (r)evolution. A report från  EREC (European Renewable Energy Council) and Greenpeace in cooperation. (http://www.erec.org/fileadmin/erec_docs/Documents/Publications/energy__r_evolution_-_a_sustainable_energy_outlook_2009-lr.pdf ).  It is an extensive detailed report of world wide possibilities to achieve a sustainable energy situation within a few decades. The means are a combination of  using energy more efficiently and development of sustainable sources.

 

The agriculture is not significant enough to be mentioned in these connections, except as concerns bioenergy.

 

But – there is more than energy. In a Swedish motor journal there was a report on a life cycle comparison of the environmental forerunner Toyota Prius and a representative for the “energy dinosaurs” , the SUV Hummer.  And Hummer won! Higher fuel use, but much higher mileage. The metals in the batteries of Prius had a high environmental cost.

Is this a special case?

What about the raw materials for low energy lamps and solar panels for instance?

 

Development figures.

September 30, 2008

On Monday morning I happened to see part of The Tällberg Conference on Climate and the Future on TV. Prominent persons from all over the world testified about the need for change. I felt good having started this blog.

 

I checked some world statistics. The World Bank is a good source.

 

Some figures for year              2000             2005:

 

Population, millions                 6076             6461

Cultivated land, %                     37.5              37.5

Energy use, kg oil eq/cap          1672             1786

Electricity use, kWh/cap            2389             2678

 

The population increases. Cultivated area is constant. But the energy use increases, also per capita. As such this is positive, it shows an development. But it seems evident that these trends cannot continue for long. The energy use has increased 14% in 5 years. And we talk about saving energy resources.

It is necessary to use resources more efficiently. It can be called “decoupling”, or increased ecological efficiency.