The terawatt challenge
Solving the world’s energy needs is going to require faith in science and technology.
From the oil crisisof the 1970s to today’s skyrocketing oil and petrol prices, the world is slowly waking up to the fact that it is living beyond its means.
The history of oil is the history of civilization during the past 100 years. Most experts agree that oil, or fossil fuels, will run out some day. Without energy, the world’s entire industrialized infrastructure would collapse like a house of cards.
By some estimates, the planet has, or had, two trillion barrels of oil. So far, mankind has gobbled up nearly half of that by consuming almost 220 million barrels of oil per day, which we still do today.
As the world’s population grows, from one billion in 1850 to more than six billion today, and as this population seeks even higher standards of living, the need for energy is predicted to grow exponentially. The United Nations projects that world population will reach
nine billion by 2075.
“To give all people on the planet the level of energy prosperity we in the developed world are used to, we would need to generate 60 terawatts around the planet, the equivalent of burning 900 million barrels of oil per day,” said Richard E Smalley, a 1996 Nobel laureate in chemistry, during a Frontiers of Materials Research symposium held at Rice University in late 2004. “And where could that amount of energy ever come from?”
Renewable energy technologies currently supply 13.3 percent of the world’s primary energy supply, and that could rise to 19 percent by 2030, according to a report published by the International Energy Agency.
Most of this is accounted for by well-established technologies (still being tweaked to yield maximum effects) such as hydropower, biomass, geothermal, wind and solar.
Progress is beingmade. Outside Leipzig, in Germany, there is a field with 33,500 photovoltaic panels aimed towards the sun. These generate enough electricity to power 1,800 homes. And, interestingly, nearby are gaping pits that used to be coal mines that were used to feed factories and power plants. Today, these environmental disasters have been turned into swan-filled lakes.
But solar power, while getting cheaper, still has a ways to go. According to a National Geographic Magazine article, less than one percent of the world’s energy comes from solar power. Its main drawback is the space required to set up solar panels. According to the article, to power the whole of the United States would require a field of solar panels the size of the state of Vermont.
Or, put another way, if solar panels covered one percent of the land that is used for agriculture worldwide, enough electricity could be produced to satisfy world consumption.
Another alternative is wind power. Europe leads the world in wind power, with electricity production from wind turbines now around 15,000 megawatts. Denmark, which produces around 3,000 megawatts from wind, satisfies about 20 percent of its electricity needs from this source of energy.
But the problem with wind turbines is that they need wind. And when there is no wind, the electricity grid still needs to fill its capacity through other means, such as coal-fired power plants, which are not easily adjustable. Because it needs to use other methods to maintain sufficient electricity supply for windless times, Denmark sometimes creates excess electricity, which it then must sell to neighbouring countries at a loss. The technology to store vast amounts of electricity in batteries is still not commercially viable and is an area of ongoing research.
At the same time, between 1981 and 1998 production costs of wind turbines were reduced by a factor of four, making it a cost-effective alternative to other forms of electricity generation.
Another form ofenergy is nuclear fission, which provides 16 percent of the world’s electrical power – 78 percent in France, 60 percent in Belgium, 20 percent in the US and 34 percent in Japan.
Yet, despite the allure of abundant power, nuclear fission has many detractors. Apart from the threat of accidents such as occurred at Chernobyl, there is the issue of waste disposal. And besides, the readily available stockpiles of uranium will not last more than another 50 years, according to some estimates.
And then there is fusion power – energy that is released when two atoms fuse into one. This is the process that powers the stars, and despite many attempts here on earth, it has yet to be harnessed in a safe and commercially viable way. But scientists around the world are certainly trying.
To solve the world’s future needs for energy will require more disruptive technologies.
Just as oil surpassed wood, coal and the horse in the past 100 years as the primary source of energy (it wasn’t that long ago that agriculture and transport were mostly muscle-powered), new technologies will someday show the way forward.
A couple of these technologies involve the ocean. One idea, still in the early phases of development, is to harness the up and down motion of waves to drive some kind of turbine. Another, which is being talked about in academic journals, is to use the temperature difference between the surface and bottom of the ocean to do the same thing.
And then of coursethere is space. According to some (maybe far-fetched) theories, space holds the key to an inexhaustible and non-polluting energy supply where space-based systems could collect the sun’s energy and beam it back to earth.
Space solar power (SSP) would employ satellites in orbit around the earth or systems on the moon’s surface equipped with solar cells, that would collect the energy and send it back to earth in the form of
SSP has been studied extensively by space agencies such as NASA, as well as universities and industry groups worldwide since the energy crisis in the 1970s. But interest amongst policymakers in building SSP faded away almost as fast as the lines at the gas pumps when the crisis subsided.
Now, with the current surge in oil prices and a shortage looming, not to mention issues surrounding global warming from the burning of fossil fuels, political interest in SSP has been revived.
Solar power from space will last as long as the sun shines and is abundant enough to provide the populations on earth with all the energy they will ever need.
According to the US Geological Survey, a part of the US government, 40 percent of the world’s energy comes from oil, 22.5 percent from natural gas, 23.3 percent from coal, 7 percent from hydroelectric, 6.5 percent from nuclear power and 0.7 percent from biomass and other methods.
There are also enormous, ongoing and global efforts towards replacing fossil fuels with biofuels such as ethanol, made from corn, to power cars.
Illinois Governor Rod Blagojevich made a recent pledge of 1.2 billion US dollars to substitute oil with home-grown energy products such as ethanol to satisfy 50 percent of Illinois’ petrol needs by 2017. And Japan has stated that all of its vehicles will be ethanol-powered by 2030.