Facts and Information on Solar Energy

April 2, 2010 · Filed Under solutions · 1 Comment 

Every fact about the Sun is hard for most of us to take in.  The numbers are so huge it makes us and our Earth seem very small and insignificant. When we feel the heat of the Sun on our face, it is hard to believe that it has come from 150 million km away. Just a tiny fraction of the Sun’s energy hits the Earth, yet every minute enough energy arrives to meet our demands for a whole year if only we could harness it properly.

Most of the energy we use is sunshine, but only a part of it is present-day sunshine. The rest is what I like to call “Pre-historic sunshine” –  sunshine that was collected by plants and marine organisms hundreds of million years ago through the process of photosynthesis and stored in a concentrated and convenient form as fossil fuels.
It has been extremely hard for anyone collecting present-day solar energy to compete with previously collected solar energy that flows out of the ground in the form of oil and gas in huge volumes at very low cost. However, one thing we can be sure about is that fossil fuels are finite and one day supply will not match demand.  When that happens there will be chaos as nations, companies and people fight over remaining reserves. We therefore need to reduce our dependence now before that happens using incentives to encourage the efficient collection of solar energy which should be with us for the next few billion years. If we do not, we will be at Peak Food time. Our oil and gas dependent food system will fail and the Earth’s population will collapse.
There is no doubt that there is more then enough current solar energy . Obviously we can’t collect it all but the question is can we collect enough to meet our needs at a price that will not ruin us?  Governments tinker with taxation of fossil fuels and subsidies for renewables, but to make a real difference to carbon emissions and at the same time slow fossil fuel depletion, international agreements will be needed.
The main methods of collecting solar energy are through exploiting the weather systems driven by the sun, using man made collecting panels or cells and most important of all, using the original solar panel, the plant leaf to collect energy in the form of both food and fuel.

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Nitrogen Fertilizer-The Downside

October 6, 2009 · Filed Under Uncategorized · Comment 

The population of the Earth has always gone up in line with our ability to provide sufficient food and it could be argued that the population explosion of the last 60 years has been possible in large part because of artificial nitrogen fertilizer.

Good crop growth depends on sufficient soil nitrogen, and in the past farmers spread manure,and used nitrogen fixing crops such as peas, beans and clover to replenish reserves. There was also imports of guano and other nitrogen rich natural deposits.

The real breakthrough came in the early twentieth century when the german chemists, Fritz Haber and Carl Bosch invented a way to use hydrogen to capture atmospheric nitrogen and form ammonia.

The application of large amounts of nitrogen fertilizer has boosted yields to such high levels that Professor Vaclav Smil of Manitoba University estimates that ‘without nitrogen fertilizers no more than 53% of today’s population could be fed at a generally inadequate per capita level of (year) 1900 diets’.

The green revolution, using high yielding new crop verieties would have been impossible without nitrogen fertilizer produced this way but has the world population expanded on the back of an unsustainable method.

The process needs vast amounts of energy which has been mainly provided by cheap natural gas and the production of nitrogen is responsible for a large part of farmings carbon emission. We know that gas supplies will eventually decline and become expensive, probably causing a switch to using coal as the feedstock, which would be much worse for carbon emissions at a time when world leaders are commiting us to huge reductios in all greenhouse gas emissions.

We could say that the availability of cheap nitrogen fertilizer has allowed the massive overpopulation of the world and that when it becomes much more expensive as demand outstrips supply, nitrogen shortages will contribute to peak food.

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