One of my friends wrote this on solar:
The fast pace of technological development is one of the most significant characteristics of our time. Today it takes only a few months to achieve the same number of important inventions and discoveries that took decades, if not centuries, in the past. Technological development helps raise standards of living around the world. Diseases that afflicted humanity for centuries have been nearly eradicated, and life expectancy
has lengthened in most countries. But many problems have not been solved yet, and others are in the offing.The two common factors that underlie many of the problems threatening our future are the fast growing population and the ever increasing consumption of resources driven by the diffusion of life-styles that have developed in industrialized societies
and are emulated in much of the world. Until the discovery of fossil fuels
and the beginning of the industrial revolution
, the sun’s energy – in its different forms, direct and indirect (such as wind and biomass) – was the sole energy source that inspired and enabled the development of human societies. Since then, and especially in the past one hundred years – a relatively short span of time – a powerful energy infrastructure that now covers practically the entire planet and is based on fossil fuels and nuclear energy
has been built. Today the world consumes 9 billion toe per year, compared with around 500 million toe in 1860. While these energy uses and infrastructure do not yet benefit billions of poor people who still try to make do with firewood, they give humanity a power over nature that earlier generations never knew; they had to survive with the renewable energy of the sun.
This power helps us live more comfortably than past generations, but while it meets new needs, it also carries the risk of irreversibly altering natural balances, both local and global. The world’s population has been growing rapidly over the last century and continues to grow. We were 1.6 billion in 1900; we have now passed the 6 billion mark. If this trend continues, the human population will rise to about 9 billion by 2050. The increasingly crowded world has also become a world of cities. Fifty percent of the population already lives in cities and the figure is expected to rise to 75 percent by the year 2050. Dozens of cities already number more than 10 million people. The invention and development of modern solar technologies began forty or fifty years ago. Tremendous progress has been made, especially in the last decade. A great number of solar, wind and biomass technologies for the production of fuel, heat and electricity are now available
or close to commercialization. They have been installed on a significant scale in both developed and developing countries. They are used in many different ways, stand-alone or incorporated in conventional energy networks and grids. They are already providing energy services to individual homes, villages and cities.