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Waiting for the energy review

by mel starrs on July 8, 2006

in Uncategorized


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©copyright 2004 UKAgriculture.com

The government’s energy review will be published next week. The Independent has the following comment on the proposed proportions of renewable energy sources:

They (Adas, analysts from Wolverhampton) have calculated that 3 per cent of all land in Britain, almost
7,000 sq km, will have to be filled with wind farms, and about 15,200
sq km given over to “biomass” crops. This implies that thousands of
acres of what are now corn fields, orchards or unused wetlands could be
transformed in the next few years into tightly packed fields of willow
trees or elephant grass. The acreage of bright yellow rape seed, used
to produce biodiesel, may also have to triple, from around 300,000
hectares to a million hectares.

However, a large field packed with coarse, woody grass over 12 feet
high may be a good way to fuel a power station but it is not everyone’s
idea of a beautiful sight. Elephant grass and coppice willow also need
a great deal of water.

The point about water required is worth remembering. Even if we do manage to get the world’s carbon dependence under control, we have to remember that there are finite resources available to us, and water is the one of the most important. Some scary irrigation facts from around the world:

More than 60 percent of the water used in the world each year is diverted
for irrigating crops. Egypt, which must irrigate all its crops, uses more
than five times as much water per capita as Switzerland. In Asia, which
has two thirds of the world’s irrigated land, 85 percent of water
goes for irrigation. A worldwide doubling in the area under irrigation
to more than 260 million hectares underpinned the “green revolution”
that kept the world fed in the late 20th century. Almost 40 percent of
the global food harvest now comes from the 17 percent of the world’s
croplands that are made productive in this way.

In some countries there is an increasing reliance on pumping underground water,often at rates that rainfall cannot replenish. Libya, for instance, by pumping”fossil” water from deep beneath the Sahara desert, uses seven times more water annually for irrigation than it receives in rainfall. India is pumping water at twice the recharge rate, causing some water tables to fall by between 1 and 3 meters a year. The country’s grain production could fall by 25 percent if it gave up groundwater “mining”.

via:: American Association for the Advancement of Science Atlas of Population & Environment
Another example of the importance of ‘joined-up thinking’ in addressing sustainability issues.

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