This is one of the most straightforward of all the climate control technologies–if Earth is trapping too much heat or the Sun is getting too hot, just block a bit of it. No matter the cause of the increased average temperatures on Earth, this solution will reduce them. Moreover, even if future needs require additional solar radiation to maintain temperatures due to some cooling event, the same shades or reflectors might be quickly redesigned and used for that purpose as well–the beginning of a global climate control system.

How It Works
No, there are not black spots in the sky or shady spots on the ground…

According to the design proposed by Roger Angel a series of thousands of thin semi-transparent shades would be placed in orbit around the sun at the Earth-Sun Lagrange point (L1, see diagram below)–a stable orbit constantly balanced between the Earth and Sun. Each of these shades would diffuse a small amount of the sunlight on the way from the Sun to the Earth thus reducing the total amount of sunlight striking the Earth.

There would be no shady spots on Earth, as most light would just pass through the shades. Even the solid opaque portions of the shade would be unlikely to cause dark shadows (umbra) due to the distance between them and the Earth. Viewing of sun spots and other solar phenomena would not be significantly impaired by the constellation of shades (imagine taking pictures through a chain length fence and focusing on something far beyond it–the fence practically disappears except for a slight fuzziness or brightness reduction in the picture).

How Much It Would Cost

Roger Angel proposes the development of electromagnetic rail guns to reduce the space launch costs to $20 per pound down from the current estimate of $10,000 per pound. Several rail guns would be required to launch payloads every 5 minutes continuously for 10 years. Total costs would be in the trillions of dollars. The development of the launch system alone would require a decade or two of serious engineering.

If these costs were averaged over the expected 50-year life of the shades, the average costs for controlling climate in this way would be on the order of $100-$200 billion per year for 50 years. Climate change impacts may last for 100-150 years, however, and the process may need to be repeated if newer technologies have not fully controlled the issue by that time.

These financing numbers are feasible with sufficient political will, however the extent of investment required for this one relatively straightforward solution should force reconsideration of other possible mitigation of these problems. Surface structure modification, complete transition to fully renewable energy, and other significant changes to current ways of doing business could all be implemented with the levels of financing required for this plan, many at much lower cost.

Potential Problems

Beyond the very high costs and the effort required to be maintained over generations to implement such a solution, there are other consequences of reducing the Earth’s temperature by limiting solar heating. Chief among those concerns is that the solar shades, because they are so far from Earth, would each reduce the sunlight all over the planet by a small amount and result in significant climate shifts. Currently, because of distances and angles, more solar heating strikes the equatorial regions than the polar regions. After implementation of the solar shades, the temperature of the whole Earth would be slightly reduced, but the temperature of the equatorial regions would be reduced more, and the polar regions may experience warming–the temperatures across the whole planet would become more similar.

While this doesn’t sound too bad, especially if you put stock in predictions of catastrophe if business as usual continues, there are substantial concerns to be dealt with even after spending the resources necessary to implement the solar shade system as this report from climate modelers points out:

“We found significant cooling of the Tropics, a warming of the polar regions and related sea ice reduction,” said Lunt. “We also found important differences in the hydrological cycle, with Sunshade World being generally drier than the pre-industrial ‘natural’ world. Average precipitation decreased by five percent with the largest decreases being in the Tropics.”

Given the 25-year development and launch cycle combined with 50 years of maintenance, the persistence of society and government support required is enormous. Without catastrophic harm occurring on a regular basis, it is difficult to see how such support could be marshaled for such an endeavor. And, with catastrophic climate events occurring on a regular basis, it is difficult to imagine that adequate resources would be available.

Low Energy Desalinization

The most plentiful resource on the Earth is salty water. In addition to the oceans, many aquifers around the globe also contain salt water, not fresh, at various depths, making it nearly ubiquitous. Fresh water is needed for industrial resources as well as agriculture and personal consumption and so is widely expected to be civilization’s limiting resource of the next century.

This salt water can be made fresh by the use of desalinization techniques, but today’s methods are often very energy intensive, suitable only for energy-rich and water-poor nations in the middle east and some island communities, who have no alternatives.

Low energy desalinization techniques (also here and here) with sufficiently low capital costs could instigate an explosion of increased agricultural productivity, industrial productivity, and improved public health all around the world. Without this achievement, increased national conflicts, and persistent health and agricultural problems will likely persist throughout the next century.

Increasing Agricultural Yields of High Quality Foods

The “green revolution” of the last century ushered in by the use of petroleum-based fertilizers, and simple but effective pesticides and herbicides caused a great increase in the productivity of agricultural around the world, especially basic grains. Instead of the population boom causing millions to starve as some expected, we have arrived in today’s world where there are regular global food surpluses (even if not evenly distributed) and obesity has become one of the dominant health issues of our time.

Creating the agricultural systems that produce the right kind of nutrients human need in the right quantities at the lowest cost of labor and resources will result in a healthier society with more productivity to focus on other developments. Many of today’s problems of malnutrition and obesity both partially result from imbalances in the food supply against what is actually required by the population. To solve both those problems, the proper incentives and system designs need to be implemented in the agriculture market.

Growth of Computational Power (Science of Prediction)

The power of computers in terms of memory and performing calculations has been increasing on a rapid exponential track for some time, and is expected to do so for the next several decades, and possibly even beyond that as engineers find methods to circumvent the current limits miniaturization, or barring that, computers will simply increase in size and power consumption to keep pace. These developments are now normally expected events by the culture at large, and have incrementally had great effect in the continually increasing productivity of the West, and the increasing societal and economic integration around the world.

None of those potential developments would necessarily lead to their inclusion in this list were it not for the now possible development of a nearly new field of science and engineering: the science of prediction and the closely related science of quantitative risk assessment. Humanity has been attempting to predict weather, economic developments, wars, disease outbreaks, and other problems for a long time, with little repeatable success. The greatly increased computational power, however, has allowed the tools available for prediction to catch up with the complex mathematics required to perform prediction. It is now a possibility that we soon can develop capabilities to anticipate and predict future problems before they cause catastrophic harm. Accurately predicting earthquakes, severe weather, future environmental problems, wars, and resource depletion can be accomplished this century with properly directed effort. The effects on future society will be profound.

Increasing Efficiency and the Supply of Sustainable Energy

Contrary to some of the other points mentioned in this article, this objective does realize its proper level of importance in the media regarding the projection of the course of the next century. The growth in demand for power that can be transmitted or carried from one place to another will continue to grow at a rapid pace, as the benefits we all obtain from that power to our health, our productivity, our social relationships, and other things, is steadily growing as well.

There is no progress to be achieved from turning our back on all these developments. However, by changing from depletable to renewable forms of energy generation and from inefficient to efficient forms of energy consumption, we can increase the benefit and reduce the potential harm and disruption caused by our increasing energy appetites.

Given the amount of other information available on this topic, I don’t need to elaborate much here in this article, but suffice it to say that the next century with either see a transformation of the world’s energy system leading to continued progress for civilization, or a practical collapse of that system as some of the sources of energy currently available become depleted.

Eradication of Infectious Diseases that Kill and Disable

Every year, up to 17 million people, many of them children, die from infectious diseases. In fact, outside of chronic conditions that are the most likely causes of death in the aged, these infectious diseases account directly and indirectly for more than one third of all deaths in the world each year, and a majority of the deaths of adults and young people. Adding in the effects from disability, both temporary and permanent, would likely triple the impact of these diseases on our society.

So great a loss of those who we expect to contribute their productivity and creativity to the world is a substantial drag to potential achievements in the next century. It is within our capability to not just control, but to eradicate most of these perennial diseases in the next century. The effect on global society towards increased investment in the future and away from a culture of fatalism would be incredible. The effect of 17 million more individuals every year working towards the good of their families and their communities would quickly lead to realized gains against all kinds of problems we face on this planet.

Increasing the Effectiveness of Education

Often overlooked or taken for granted, whether or not our civilization is prepared and capable of achieving progress depends on a more skilled and knowledgeable society. The proper functioning of representative governments depends on it, as well as the beneficial functioning of all kinds of organizations. If science is to find the answers to these challenges listed above, there must be a great number of highly trained scientists and engineers to produce those solutions and a highly educated population to consent and implement them. Societies that remain closed to or fearful of new theories, ideas, or foreign cultures will find significant improvement difficult if not impossible. Education is the key to creating the kind of fertile ground for progress that is required.

While there are numerous good models of highly effective education in different places, there are very few places that function highly in all areas. Even nations, cities, or schools with high reputations in one subject area rarely excel in all areas, even though the models are visible and available for all to duplicate. As such, even the highly educated from the best schools in the best nations, have wasted time in many courses for many years over the course of their academic training. When considering that those who have been lightly trained at sub-standard schools have likely wasted more time, there is considerable room for improvement worldwide. As the methods of education begin to be subjected to more scientific scrutiny, as the facts have already been, the way education is conducted will surely change. If that change is transformative on the world level utilizing best practices from wherever they are found, multiplicative dividends to global society can result.

Conclusion

These are transformative steps to progress. Whether our civilization takes these steps and to what degree will determine how much progress is made in the next century. Without these some incremental progress is still to be expected, but why should we settle for that, when we are on the cusp of so much more? I expect one way or another civilization will continue on through the next century, but realizing these six opportunities would truly make it a century of progress.

Asteroids inhabit the space near to Earth and contain high percentages of metals and other minerals that are more rare on Earth. Mineral- and metal-rich asteroids require less energy to visit than the surfaces of moons or other planets, while the amounts of the resources they hold are readily determinable from telescope observation from Earth.

This image of the Gaspra asteroid from JPL.

As this article makes clear, the value of these minerals for different purposes are high, but not yet high enough to offset the costs to utilize them. What this interesting study makes clear, however, is that we have the means to predict economically when real space exploration, in terms of a more permanent human presence in space will begin.

Just looking at our world’s consumption of important metals, we can see from the graphs below that steel and gold are all increasing at a fairly rapid rate over time, not to mention the many other valuable metals like nickel, magnesium, platinum, etc. Increases in consumption drives increases in price as the easy to reach supplies on Earth are depleted. Unless we were to completely or drastically reduce our need for metals in buildings, vehicles, and consumer goods, it is inevitable that these commodities will reach the point that these asteroids become profitable ventures for courageous individuals.

Steel production data from here and here. Gold production data from here.

The other side of this equation is reduction in cost of access to space. Launch vehicle prices have been decreasing over time, as more competition between national government space programs and commercial corporations has developed. This data shows that as of 2000, the real price of access to Low Earth Orbit (LEO) had fallen to $22,000 per kilogram, while access to Geosychronous Orbit (GSO) has fallen to about $25,000 per kilogram. These values demonstrate a reduction of around 40% from the prior decade for GSO, and a reduction of around 15% for LEO. These costs would be directly applied to the capital costs of developing a mine in space.

While launch costs are surely one of the most significant at the moment, return costs not to mention engineering costs required to develop the necessary equipment will also be substantial at least at first.

So, the balance between the value of the minerals and the costs to retrieving them will determine when this equation becomes positive in favor of pulling or pushing us off the planet. Until then, as the world economy develops over time, demand will be increasing pushing the prices of these commodities up as more of the world approaches the lifestyle of the rich countries.

What is Hydrogen and Where Does It Come From ?

Hydrogen is a very light gas at normal temperatures and pressures on Earth and does not occur naturally in any large quantities. It breaks down in the atmosphere or rises to the very edge of space where it is blown away by solar wind. When burned in air or with pure oxygen it produces only water vapor.

But, in terms of the fuel and energy infrastructure, hydrogen is nothing more than a substance for portable energy storage. It fills exactly the same role as a battery when combined with a device that can turn the hydrogen into power. When people speak of hydrogen powered automobiles, they are really saying “electric cars”. From an overall energy system point of view there is no difference. Hydrogen has to be produced by another form of energy just like a battery has to be recharged with electricity from the grid.

Today most hydrogen comes from a chemical process involving natural gas, a fossil fuel, with some produced by the electrical breakdown of water into hydrogen and oxygen. Of course, the electrical power to breakdown the water could be supplied by anything from coal to wind.

So, Do We Need Hydrogen Cars

The benefits of hydrogen automobiles are the same as the benefits of electric cars–reduced pollution and less reliance on any single source or type of energy. Large power plants prove more cost effective for pollution control than thousands of automobiles, and power plants have already been designed to turn a wide variety of energy sources into electricity. That electricity can be used to create hydrogen or charge batteries.

The difference is that recently hydrogen fuel cell systems for cars have proven a little easier to engineer for long ranges than battery systems. In time, it is likely that the difference will even out. Both batteries and hydrogen tanks have safety risks, but they are being addressed and in the end will be no worse than the risk of carrying 12 or more gallons of gasoline around with us.

The cost effectiveness of hydrogen service stations has yet to be demonstrated, but will likely not cost much more than the equivalent amount of energy in electricity given a large enough distribution network. Unlike gasoline and diesel, hydrogen would mostly be produced on site at the service station as opposed to being trucked around cutting out a major portion of the current fuel delivery infrastructure.

The Future?

Whether this is the start of anything new is anyone’s guess at this point. Competition between diesel-electric plug-in hybrids, all-electric cars, and hydrogen fuel cell vehicles will sort out the winners in the marketplace. They all offer similar benefits and increases in efficiency today. How well those technologies can be matured will determine which technology wins, or perhaps several will find their particular niches. Time will tell on that score. For now, we can be certain some kind of change is coming, and that we will see the equivalent of a slow motion format war among automobiles along the lines of Betamax/VHS or HD-DVD/BluRay.

While “green” or renewable energy technologies are often seen as the rival against traditional fossil fuel technologies in some kind of epic battle, they can actually sometimes enhance and support each other. Recent news from wind power companies suggests that they may be able to move their turbines offshore to deep water out of sight of land and away from wind-blocking obstructions by employing technology developed for deep water oil and gas exploration and production operations.

This recent article in The Economist, reviews recent advances and planning for off shore wind energy production. While near-shore wind farms have been proposed (near coastal Massachusetts and Texas) in the United States, none have actually begun construction. Delays caused by opposition to the aesthetics or potential environmental problems of the wind turbines sites have plagued these plans. Near the United Kingdom and Denmark, offshore wind farms are already in operation, but they include turbines that are mounted to fixed foundations on the floor of the sea.

Offshore, with no obstructions to the flow of the wind, the average wind speed is double that over the land. Since, the energy contained in a flowing gas follows an exponential law, the same turbine could generate significantly more energy when placed offshore than it could on land. For example, wind blowing at 10 meters per second contains five times the energy of wind blowing half that fast.

In addition to greatly increased energy output and decreased worry about public opposition, comes the knowledge that these floating wind turbines are based on proven technology (floating oil and gas platforms). The Gulf of Mexico alone currently contains thousands of these platforms operating in deep water. At the very least, these floating turbines provide a means for these sites in the gulf to continue producing energy long after the oil and gas has been consumed.

There are a few potential challenges to fully implementing this technology that we should be aware of, however. One is that due to the harsh environment such as severe storms, the turbines may prove to be maintenance nightmares. The other is that an electric infrastructure will have to be built between whatever body of water the turbines are floating in and the mainland. While this is also proven technology, it does limit the distance from land at which these turbines can be placed. Don’t expect to see turbines floating in the middle of the Pacific Ocean anytime soon. That said, these challenges are relatively minor compared to other potential clean energy improvements.

In the near future, expect to see the traditional oil and gas producers get involved in this technology. As they already have working relationships with the floating platform builders and they already perform regular maintenance in the areas where these wind turbines might be placed. As a method of diversification into non-fossil fuel energy sources with a guaranteed near term payback, this is an ideal technology from most energy companies’ perspective.

As the article states, this idea of constructing large solar power collection facilities in space and beaming the energy back to Earth via microwaves or lasers or other means has been floating around since the 1960s. While from the beginning we have had the technology to do this kind of thing, the costs were just too high for this kind of system to compete with ground-based electric utilities. The question we have now is has that equation changed sufficiently to make these power stations a reality.

Benefits

The reason for constructing solar power in space versus on the ground is that you turn what would be a periodic power source with a roughly 12 hour on/off cycle into a nearly constant power source that also never has to worry about clouds or other weather or even air decreasing the amount of sunlight. So, you get more than 200% of the power out of the same hardware than you would on the ground. Also, the normal benefits of solar power apply as well: it is pollution free during operation, and it is not dependent on the provision of fuel through international trade and the economic and political volatility that sometimes creates.

Costs

The costs of this approach have been reducing steadily since the 1960s. Solar power technology has become much more efficient (meaning less mass would have to be launched into space) and much less expensive. Even greater increases in efficiency and cost effectiveness are likely in the next decade. The most significant cost, however, is access to space, specifically geosynchronous orbit. These costs have not changed much in the past 20 years, although that, too, could be changing with the increase in private competition occurring in this industry. Given the challenges, however, I would not expect a significant private capability to access high orbits for the next 20 years. That area will remain primarily government funded and relatively expensive. But, given the improvements in solar technology, launch costs for a given amount of power capacity are decreasing.

Leapfrog

Leapfrogging refers to the tendency of developing economies to take the next best available technology off the shelf as they add infrastructure, which many times causes those economies to end up with higher technology infrastructure than established developed economies have. So, could space solar power be one of those technologies, shunned by the developed West and taken up by developing India and China. The CNN article brings up that possibility. With enormous costs to electrify their nations from a minimal starting point, India and China can consider this technology from a clean slate perspective. Given soaring fuel costs for all energy types around the world, this strategy may prove to be an excellent long term move. With a steady source of energy totally independent from most Earthly politics, and any pressures on the supply side, they may have a real recipe for sustainable long term energy development.