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History Of Solar Energy — Knowledge For The FutureThe history of solar energy is important knowledge in knowing something about the cause of global warming and what alternate energy sources to use. Understanding our past helps us live a better and sustainable future. It helps us also to understand what is solar energy and how to best use it. Ah, you’re here because you believe, with me, that if you want to move forward we need to first understand the past? The history of solar energy is important? Wonderful. Sit down with me, around the fire, and together we will delve into the fascinating history of solar energy just a little. OK?
Of course, you know that using renewable energy is nothing new. It’s what people used throughout recorded history before coal, oil and gas were found. They burned what we now call biomass. Wood, dried animal dung and peat for instance, for heat and light. All part and parcel of the history of solar energy.
Before the wide-spread use of fossil fuels, windmills and water mills have been used for centuries as power sources for small industrial purposes. For example, the small but resourceful country of The Netherlands is known for its use of windmills for land reclamation, as well as for various industrial purposes. Yes, wind, hydropower, and biomass power are all forms of solar energy. The present advantage of renewable energy sources is great. The problem with solar, wind and waterpower always was that they could be used but not easily stored. Once the sun goes down its warmth and light goes with it till the next morning. Wood and animal dung were the most common forms of stored solar energy and still are in many parts of the world. Now you can put the sun in your pocket and use it to charge your electric appliances! Amazing. The is one example among many of this latest technology.
Sun worship by ancient civilisations is evidence of recognition of the sun’s central importance in sustaining life—renewing energy. Native North- and South-American peoples worshipped the sun. So did the Babylonians, ancient Hindus, Persians and Egyptians. The Easter bonfire and the Yule log at Christmas time are remnants of European sun worship. In ancient Greece the deities of the sun were Helios and Apollo, with many temples devoted to them. Ancient Greek interest in the sun transcended religious purposes. They were the first to use passive solar design in their housing. As early as 400BC entire Greek cities were built in this way. The Romans later improved on these designs and they were the first to use glass for windows, thereby trapping solar warmth. The Romans even stipulated by law that it was an offence to obscure a neighbour’s access to sunlight. They were the first to use glasshouses to create the right growing conditions for exotic plants and seeds they brought to Rome from far-flung corners of their empire.
In the 18th century a scientist discovered that boiling temperatures could be achieved under glass covering a box. Next someone thought of putting a black water tank inside to heat water. In 1909 Californian William Bailey separated the water tank from he solar collector to keep the water warm during the night and presto, this is the prototype for many solar water heaters used today. So, the first solar hot water heaters were of course diy solar heating.
When Americans and Europeans were developing the first information highway between their continents, the telegraph, they found out something about selenium, a trace mineral first discovered in 1818. When sunlight shines on it its conductivity rises as much as a thousand fold, compared to being kept in pure darkness. This produces an electrical current and is known as the photovoltaic effect, taking place in solar cells used to build solar electrical panels.
Three Americans working on small transistors in the early 1950’s found that if you build transistors in a certain way, using silicon, you would have an effective solar cell, or PV cell. If it were not for the satellite industry the PV cell would not have taken off. They were very expensive with no use for them. Satellites had no other opportunities for fuel sources up in space but PV cells. Their use of PV cells then made the solar cell industry a sustainable one. The global solar cell industry is now growing by 25% per year. There are many advantages of solar energy with which fossil fuels just cannot compete, so the future for solar cell use appears bright.
Modern technology has given us further possibilities to store and use renewable energy. Interestingly such technological developments have emerged from necessity, the good old mother of invention. The beginnings of modern wind technology are found in Denmark when during World Wars I and II access to fossil fuels was difficult. Other alternative technologies, such as using gas to power cars originate in such challenging times. During the 1960’s the public’s consciousness of a need to use renewable energy grew and the oil crises of the 1973 and 1979-1980 further boosted its development.
Centuries-old practices of passive solar design received re-appraisal and design got smarter. Double-glazed windows facing in the predominant sunny side, skylights, insulated walls and so on, are examples of this. Hybrid cars that use electricity and petrol, and vehicles that run on natural gas, hydrogen, or biodiesel are all symptoms of a growing interest in renewable energy. Solar roof shingles, solar paint and solar nanotechnology can also make their contributions to energy efficient home design. Powerglass is a thin polymer photovoltaic layer which can be directly applied to windows and roofs. Start thinking of high-rise buildings as power plants! These further exciting tastes of a future where global warming prevention and sustainability and sustainable development are real possibilities. The cost of applying renewable energy technology is getting lower as applications are mass-produced and the price of fossil fuels increases. It can be done. Photovoltaics are certainly part of the future. Want to know how you can be part of it? Read the
An interesting example of an entire country turning to renewable energy is that of Iceland. It has abundant hydro- and Geothermal Energy sources, allowing over 99% of the country's electricity to be generated from renewable sources. Most of its urban household heating is derived from geothermal processes. Iceland is now working on using their green electricity source to produce hydrogen as fuel for its public transport, fishing fleet and private cars. Israel produces much of its domestic heating needs through solar energy. Germany, while not being ‘rich’ in natural wind resources, boasts one-third of global wind generation capacity. And Spain is the second-ranked windpower-using country in the world. Cautiously developing countries like Bhutan are seeking to implement local solar power approaches in rural areas where people now ruin their health by the use of kerosene in their small closed homes.
Be like selenium in how you live your life. But sustainable living cannot be achieved through technology alone. Making the effort to know and understand others, learning from those who successfully live within severe limits and with dependence on others, will really make the world go round—sustainably. I wish to acknowledge the work of John Perlin on the history of human solar energy applications, some of which is the source for information on this page. I've already mentioned his book From Space to Earth: The Story of Solar Electricity above. In addition there is A Forest Journey: The Story of Wood and Civilization |
Photo: Solid Tscheik
