For most of history, humanity has relied on earth-based energies. It was wood for early humans, and many Mainers still rely on wood for heat. An exception was water power to run mills to grind grain, cut lumber and power textile looms. The industrial revolution relied on coal, an earth-based fuel. In the 20th century, more earth-based fuels powered the unprecedented advances in transportation and other technology — refined petroleum for gasoline, diesel and heating oil, natural gas and propane for heating and to run machines and uranium for nuclear plants to generate electricity.
Given the threat to the environment from fossil fuels and nuclear power, humanity is poised to make a profound move from one source to another. It is time to look to the sky.
Wind power for electricity, which in turn can charge vehicle batteries and power home heaters, comes from the unevenly heated surface of the Earth. The sun heats up land faster than water, and wind is the result of cooler, heavier air moving toward the areas where warmer, lighter air is rising.
The potential for wind power is tremendous. Critics who suggest it is a fad that will never fill more than a niche lack the imagination to envision hundreds of sea-based wind towers, or perhaps thousands of smaller, community based turbines. Emerging technology will grow in leaps and bounds to capture the electricity produced by wind.
Solar power, directly from the sun, is another source. It can be captured in two ways. Devices are being improved dramatically to heat water which in turn heats buildings or is consumed for showers and washing dishes. The sun also is being harnessed in photovoltaic devices, which turn sunlight directly into flowing electrons. Such things as roof shingles that double as photovoltaics are being perfected. Again, the potential is tremendous.
Tidal power, driven by the moon, is another sky-based energy. So is hydro power, an old energy source which begins when the sun evaporates water, which later falls as rain and flows downhill.
As the crisis at the Fukushima nuclear power plant shows, earth-based energy has serious shortcomings.
The world is in a troubling, perhaps confusing limbo between two models of energy, the old earth-based and the emerging sky-based. Desperation seems to mark the drive to squeeze out the last earth-based fuels. Mountain-tops are leveled in the search for coal. Deep ledge rock is shattered in the search for natural gas. Oil-drilling rigs are built in dangerous, deep waters.
The developed world will face either an apocalyptic, painful end to its reliance on fossil fuels — wars, shortages, famine — or it will embrace the new paradigm willingly. But the new technology must be jump-started with investment, much of it public funds. It is time our leaders get their heads out of uranium shafts and oil wells and look to the sun and moon.