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The Limits of the Earth, Part 2: Expanding the Limits

The views expressed are those of the author and are not necessarily those of Scientific American.

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This is part two of a two-part series on the limits of human economic growth on planet Earth.  Part one details some of the environmental and natural resource challenges we’re up against. Part two, here, looks at the ultimate size of the resource pool and solutions to our problems.  Both parts are based on Ramez Naam’s new book, The Infinite Resource: The Power of Ideas on a Finite Planet

The Solution: Growing the Pie

As part one of this series showed, we are up against incredible challenges: feeding a world with a rapidly growing appetite, the continuing loss of the world’s precious forests, the ongoing collapse of fish species in the oceans, the rapid depletion of our fresh water resources, and the over-arching threat of climate change, which makes all others far worse.

Ending growth isn’t a realistic option.  Billions of people in the developing world want access to more resources, deserve those resources as much as those of us in the rich world do, and need them in order to rise out of poverty.   Growth won’t end without a struggle.  And that struggle could turn violent, as it has in the past.

There’s only one acceptable way out of our current predicament.  And that is to grow the total pie of resources available to the world’s inhabitants.  And a close look at the numbers and at the human history of innovation suggests this is possible.


No resource has driven more discussion of impending limits to growth than food.  Malthus – the original proponent of a near term limit to growth – wrote in the late 18th century that population would always grow exponentially, while food production could at best grow linearly.  Thus, humanity was doomed to remain in what we now refer to as the Malthusian Trap.

More recently, in 1968, environmentalist Paul Ehrlich opened his best seller The Population Bomb with the lines. “The battle to feed humanity is over.  In the 1970s the world will undergo famines – hundreds of millions of people are going to starve to death in spite of any crash programs embarked upon now.  At this late date, nothing can prevent a substantial increase in the world death rate.”

Both Malthus and Ehrlich were wrong.  Population did expand, but so did food production.  Since Ehrlich wrote The Population Bomb, the population has doubled and death rates have declined.  Food yields – the amount grown per acre – have nearly tripled.  That increase in food yields has been driven by new seeds, better farming methods, and increased availability of fertilizer and pesticides.

But increasing yields aren’t anything new.  The yield growth since the 1960s has been dramatic, but it’s part of a process that’s been going on for more than 10,000 years.  In pre-historic times, it took perhaps 3,000 acres of land to feed one hunter gatherer.  Today it takes about 1/3 of one acre to feed the average person on earth.  We’ve increased the amount of food grown per acre by a factor of 10,000 in 10,000 years.

Figure 1 - Since pre-history, humans have increased the food output of an acre of land by a factor of 10,000. See The Infinite Resource: Power of Ideas on a Finite Planet for full data sources involved in this graph.

Figure 1 - Since pre-history, humans have increased the food output of an acre of land by a factor of 10,000. See The Infinite Resource: Power of Ideas on a Finite Planet for full data sources involved in this graph.

Even with this tremendous surge in food yields, we know that there’s headroom.  Current farms convert less than 0.1% of the solar energy that strikes them into calories consumable by humans.    The theoretical limit of photosynthesis is around 13% conversion of sunlight into calories.  We may never reach that theoretical limit, but even if we could reach, say, 3% conversion, we would be growing thirty times as much food per acre as we are now, enough to feed a population far larger than humanity is ever projected to reach.

Closer to the present, there are more practical and specific reasons to believe that feeding the world is possible.  Today, global grain yields average around 3.5 tons per hectare. In the US, they average around 7 tons per hectare.  That difference in yield primarily reflects more access to capital and energy.  US farmers (and farmers in other rich countries) can afford fertilizer, mechanized farm equipment, irrigation systems, pesticides, and other tools that boost agricultural yields.  Bringing developing world farmers access to the same tools would boost yields as well, potentially doubling them, which is more than the 70% increase the FAO believes is required by 2050.   Indeed, the best farms in the US routinely get double the US average yield, so even this level is far from the maximum achievable.

Figure 2 - Food yields in the US and other developed nations are twice those of the world as a whole. If the world as a whole had food yields similar to those of the US, we would already have sufficient food production to meet the demand expected by 2050. Source: FAO

Figure 2 - Food yields in the US and other developed nations are twice those of the world as a whole. If the world as a whole had food yields similar to those of the US, we would already have sufficient food production to meet the demand expected by 2050. Source: FAO

There may be other, less capital-and energy intensive routes as well.  The yield gains over the last half century have come primarily from better seeds. And we know that further gains by seed improvements are possible.  On intriguing possibility is to upgrade the photosynthesis pathways in wheat, rice, and millet.  Those staple crops use C3 photosynthesis.  Corn and sugarcane, on the other hand, use a newer photosynthetic pathway called C4.  And as a result, Corn yields about 70% more grain per acre than wheat or rice.   The Gates Foundation and other non-profits are working on ways to integrate C4 genes into rice and wheat now.

What of fertilizer? Nitrogen fertilizer is made from natural gas today, in a process that gives off greenhouse gases. Multiple groups, however, have shown that fertilizer can be synthesized from wind power and nitrogen in the air (where it makes up 78% of the atmosphere).  An even more radical approach would be to borrow a trick from legumes.  Soy and other legumes fertilize themselves (with help from symbiotic bacteria) by pulling nitrogen from the atmosphere themselves.  Early stage projects funded by the Gates Foundation and elsewhere are evaluating whether wheat, corn, rice, and other cereals could be engineered to fertilize themselves from the air in the same way, reducing both the need to apply artificial fertilizer, and the nitrogen runoff that results from it.

Advances in how we produce food could also have a substantial impact on our overfishing of the seas.  Wild fish are under threat of extinction because they’re hunted to feed us.  Yet land animals that we farm are under no threat of extinction.  Shifting from hunting fish to farming fish – where the farmers have the incentive to keep their stocks healthy – could do a tremendous amount of good for wild fish.  Over the last few decades, the tonnage of fish farmed has soared, even as the tonnage of fish caught from the wild has stayed stagnant.  Advances in sustainable fish farming could take this even further, creating fish farms that are cleaner and better for the oceans around them, while able to produce protein far more efficiently than land animals, and removing the threat of extinction from wild fish.

Figure 3 - Wild fish catch has stagnated since the 1990s, as declining wild fish populations have made it harder and harder to bring fish in.  Meanwhile, aquaculture (farmed fish) has boomed to take up the slack. Source: FAO

Figure 3 - Wild fish catch has stagnated since the 1990s, as declining wild fish populations have made it harder and harder to bring fish in. Meanwhile, aquaculture (farmed fish) has boomed to take up the slack. Source: FAO

In short, the planet’s ultimate limit on food production is many times higher than our projected needs.

That, in turn, leads to an even more intriguing possibility.  If we could raise food yields faster than demand, could we shrink the amount of land we use to farm?  For instance, between now and 2100, total food demand may roughly double (driven more by increasing meat consumption than by population).  If, in that timeframe, we could triple farm yields, then we could, potentially, grow all the food necessary to meet demand only two thirds of the land area used today.  That, in turn, would free up roughly 10% of the world’s land area, which could be returned to wilderness, to managed forest, or some other use.   Whether or not we’d do this depends on an enormous number of factors.  Humanity may or may not decide to reforest the planet or return land to wilderness.  But if we innovate fast enough in lifting crop yields, we would have the option.


We live on a water world.   70% of the world’s surface is covered in water.  Yet the vast majority of that water – around 97% of it – is salt water.  Another 2% is locked up in ice caps and glaciers.  Only around 1% of the world’s water is fresh, and of that, humanity can only easily access about a tenth, or 0.1%.

Figure 4 - Humans access only a tiny fraction of the Earth's available water.  Most of the rest is salt water. Source: USGS.

Figure 4 - Humans access only a tiny fraction of the Earth's available water. Most of the rest is salt water. Source: USGS.

If we could efficiently convert salt water to fresh, we’d have access to a vast supply of water to use in growing crops and sustaining human civilization.  For decades, desalination has been considered a deeply anti-environmental process, though.  It’s energy intensive.  As a result, it releases huge amounts of greenhouse gases.  Any attempt to increase fresh water access through desalination would have environmental consequences too dire to make the process worthwhile.

That view is out of date. From the time of the ancient Greeks through the late 1960s, desalination technology barely changed at all: boil water, capture steam, let the steam condense into fresh water.  That process is incredibly energy intensive.

In the late 60s, however, two scientists at UCLA set out to see if they could mimic a feature of the biological membranes around cells. Cell membranes are selectively permeable.  They can allow water and some molecules to pass through them while blocking out others.  The resulting discoveries by Stanley Loeb and Srinivasa Sourirajan set off a long sequence of innovations in desalination using semi-permeable membranes.  As a result, the energy needed to desalinate a gallon of water has fallen by a nearly factor of 10 since 1970.

Figure 5 - The amount of energy required to desalinate water has dropped by nearly a factor of 10 since 1970.  Source: Menachem and Elimelech, “The Future of Seawater Desalination”, Science (2011)

Figure 5 - The amount of energy required to desalinate water has dropped by nearly a factor of 10 since 1970. Source: Menachem and Elimelech, “The Future of Seawater Desalination”, Science (2011)

The process is sufficiently cheap now that modern plants sell desalinated water at around 5 gallons per penny, or 500 gallons per US dollar.  That is still too expensive for bulk use in agriculture, but it’s approaching the price where large scale desalination becomes truly feasible.

Of course, many dry areas are also inland, but the same technologies that can desalinate water cheaply can also help filter and recycle dirty water cheaply, allowing communities to re-use wastewater.

Ultimately, with sufficient energy and with continued improvement in desalination technology, we can have access to water supplies many times larger than any projected human need.  Those are two big ifs, but they’re far from inconceivable.


Finally, let’s come to energy, and with it, climate change. Most human energy use today is from fossil fuels, and this directly leads to the CO2 emissions that are warming the planet.  Over the coming years we need to reduce our greenhouse gas emissions by at least 80% (and possibly more).  At the same time, the demands of the rising poor are going to push us to consume nearly twice as much energy as we do now by 2050.

Fortunately, the physical resources of the planet are more than up to the task.  As I’ve written before in Scientific American, the sun strikes the Earth with roughly 5,000 times as much energy as we consume from all sources combined.  Some of that energy differentially heats the atmosphere, driving wind.  Some of it evaporates water, which later comes down as rain or snow, creating hydro power.  And the largest share of it directly strikes the surface of the Earth as photons.

That energy is so vast that solar panels on less than 0.3% of the Earth’s land area would supply many times more energy than humanity needs for the next few decades.

Figure 6 - Only 0.3% of the Earth's land area would be required to meet human energy needs with current efficiency solar panels. Image courtesy of

Figure 6 - Only 0.3% of the Earth's land area would be required to meet human energy needs with current efficiency solar panels. Image courtesy of

0.3% of the Earth’s land area is nothing to sneeze at. At the same time, it’s roughly 1/100th of the area that we use to grow crops and graze livestock.  And it’s 1/60th of the area covered by the world’s deserts.  With a small fraction of the planet’s deserts we could capture abundant energy to power the world.

The problems with renewable energy today have primarily been twofold: Cost and storage. Renewables have been far more expensive than fossil fuels.  And they are intermittent, not always available when you need them (at night, for instance, or when the wind isn’t blowing).   But both problems are solvable.

On the cost front, solar power is now approaching the price of grid electricity in the sunny parts of the world.  It’s done this by plunging in cost over the last 30 years.  A watt of solar power today costs just 1/20th of what it did in 1980, a staggering decline.

Figure 7 - The cost of solar power has dropped by a factor of 20 over the last 33 years. Within the next 15 years, on current path, it will be cheaper than both coal and natural gas across most of the planet. Source: NREL  Background Image: Ramez Naam

Figure 7 - The cost of solar power has dropped by a factor of 20 over the last 33 years. Within the next 15 years, on current path, it will be cheaper than both coal and natural gas across most of the planet. Source: NREL Background Image: Ramez Naam

On current pace, by 2020 to 2025, solar power will be cheaper than electricity from coal or natural gas across the large majority of the planet, including China, India, and most of the developing world, where energy use is rising fastest.

Of course, past trends aren’t guarantees of future performance.  To continue the cost plunge, we’ll need to innovate in the design and construction of solar modules, in new ways to deploy large solar arrays that cut deployment costs, in the cost of invertors (which convert DC solar electricity to AC grid electricity) and other equipment that must come with the core solar modules.  Those advances are neither trivial nor guaranteed.  They require a continued investment in R&D to achieve.

Nevertheless, there seem to be good odds that, within the next few decades, if not the next one decade, solar power will be capable of providing cheap, abundant, carbon-free electricity in a way that can be scaled around the world.

The second problem with renewables is storage.  We use energy when the sun isn’t shining and when the wind isn’t blowing.  Germany has demonstrated that renewables can provide up to about 40% of the electricity used in a power grid on their own.  Beyond that, we need a large scale way to store the energy, and to keep the overall cost of renewables down, we need to store it cheaply.   We also use energy in our vehicles, for which we need a way to store it densely – more stored energy in less mass.  There’s a case to be made that today, storage is a bigger challenge than energy collection itself.

Fortunately, human ingenuity is dropping the price of batteries, as well, and increasing the amount of power that can be stored.   Between 1991 and 2005, the price of storing a watt-hour of electricity in a lithium ion battery dropped by a factor of around 10, from $3.20 per watt hour to just over $0.30 per watt hour.   In the same timeframe, the amount of energy that could be stored in lithium ion batteries of a given weight (their energy density) more than doubled, from under 90 watt hours per kilogram to more than 200 watt hours per kilogram.

That pace of improvement of both price and density is faster than the corresponding pace of improvement of solar and wind.  In a typical 15- year period, the price of solar cells falls by around a factor of three, while the prices of batteries have fallen by around a factor of 10.   If the learning curve of battery technologies can be maintained, the ability to store energy will advance faster than the ability to collect it, and overall prices will keep falling.

Figure 8 - Between 1991 and 2005, the price of laptop batteries dropped by nearly 10x, and the amount of energy stored per weight more than doubled.  Source: David Anderson and Dalia Patino-Echeverri, "An Evaluation of Current and Future Costs for Lithium-Ion Batteries for Use in Electrified Vehicle Powertrains."

Figure 8 - Between 1991 and 2005, the price of laptop batteries dropped by nearly 10x, and the amount of energy stored per weight more than doubled. Source: David Anderson and Dalia Patino-Echeverri, "An Evaluation of Current and Future Costs for Lithium-Ion Batteries for Use in Electrified Vehicle Powertrains."

On the horizon are new battery technologies:  solid state batteries (made like transistors) and metal-air batteries.  At the upper end, metal-air batteries could store more than ten times the amount of energy that lithium-ion batteries do, and correspondingly drop the cost.  That would give batteries an energy density similar to that of fossil fuels, meaning that electric vehicles (or even electric aircraft) with ranges similar to – or perhaps greater than – fossil fueled vehicles would be possible.

To be clear, there are substantial technical hurdles here too – metal-air batteries aren’t yet to the point that they can be charged and discharged the many thousands of times that a grid-scale or electric vehicle battery needs to be.  But the basic physics and chemistry tell us that much higher energy densities than we see today are possible, and the long history of driving down the price of energy storage gives us reason to believe that it’s possible to keep doing so.

Energy, in short, is abundant.  Carbon-free energy, the sort that would allow us to keep growing energy use while freeing ourselves from fossil fuels, is abundant.  The problem isn’t solved, to be clear.  Far from it.  Huge challenges remain in innovating to bring the cost of renewables and storage down.  Even then, deployment will be a gigantic undertaking.  But the limiting factor on our use of clean energy – for the next few centuries, at least – isn’t the available resource. It’s our cleverness and ingenuity in learning to harness it cheaply and efficiently.

Growth Without Growth

I’ve focused the last few sections how large our ultimate physical resource base is.  The ultimate supplies of energy, of potential food, and of potentially drinkable water for the planet are all hundreds of times greater than we can see humanity needing for the next century.

Yet if physical resource growth continues unabated, it will eventually consume any resource base, no matter how large.  Could it be, though, that we can grow our economy and our well-being without growing our consumption of physical resources?  There are reasons to think so.


Let’s start with population.  Malthus thought of population growth as an exponential process, doomed to consume all available resources.  And for quite some time, human population did grow exponentially.  But those days appear to be over.

In Brazil, two generations ago, the average woman had 6 children over the course of her lifetime.  Now, the average woman in Brazil has just 1.8 children over her lifetime.  That number isn’t enough to even maintain the population.  If fertility doesn’t rise, Brazil’s population will shrink over time.

Brazil is just one example.   Everywhere that incomes rise, that education rises, and that women gain more opportunity outside of the home, fertility rates drop.   European women now have around 1.5 children on average over the course of their lifetimes.  Russian women are similar.  South Korean women have only 1.3 children, on average, over the course of their lives.

Around the world as a whole, the average number of children a woman will have in her lifetime has dropped in half over the last 50-odd years, from 4.9 children per woman in 1960 to 2.5 children per woman around the world in 2011.  When fertility drops below 2.1, population stops growing.

Figure 9 - Around the world, the number of children born per woman over her lifetime has dropped from 5 in 1950 to less than 2.5 today.  When the number drops near 2 in the coming decades, population will plateau. Source: World Bank.  Background Image: Alejandra Quintero Sinisterra

Figure 9 - Around the world, the number of children born per woman over her lifetime has dropped from 5 in 1950 to less than 2.5 today. When the number drops near 2 in the coming decades, population will plateau. Source: World Bank. Background Image: Alejandra Quintero Sinisterra

As a result, between 2050 and 2100, something almost unprecedented in the history of the world is likely to occur.   The world’s population is likely to plateau between 9 and 10 billion people.  And after that, so long as wealth and education continue to rise, the world’s population is likely to drop.

The Great Decoupling:

So population will reach a maximum.  What of resource consumption per person?   There, too, we see signs of a slowdown of growth, or in some cases, a complete halt to growth, or even a reduction in consumption.

Consider US oil consumption.  While the average American consumed more than 30 barrels of oil a year in 1972, today he or she consumes only around 19 barrels of oil a year, and still dropping.

Figure 10 - The average American uses a third less oil than in 1972. The International Energy Agency forecasts even further declines to come. Source: IEA.

Figure 10 - The average American uses a third less oil than in 1972. The International Energy Agency forecasts even further declines to come. Source: IEA.

Some of this is a shift away from oil and to other sources of energy.  But summing up all energy sources combined, the average American uses slightly less energy than in the 1970s, even as per capita GDP has doubled, living area per person has nearly doubled, and life expectancy has risen by more than 8 years.

In fact, if we plot US GDP per person vs. US energy per person and US CO2 emissions per person, we see GDP (economic activity) pulling away from our use of energy and our CO2 emissions.

Figure 11 - US GDP Per Capita has roughly doubled since 1970, while energy use and CO2 emissions per capita have dropped slightly.  More wealth does not have to mean more consumption or more pollution. Source: World Bank.

Figure 11 - US GDP Per Capita has roughly doubled since 1970, while energy use and CO2 emissions per capita have dropped slightly. More wealth does not have to mean more consumption or more pollution. Source: World Bank.

Some will argue that this is a result of the US having outsourced energy US and CO2 emissions to other parts of the world (e.g., China).  And that is partially true.  Yet a look at the same numbers globally shows a similar pattern.  CO2 emissions and energy use per capita are rising, but not nearly as quickly as GDP per capita.

Figure 12 - On a global scale, GDP is decoupling from energy use and CO2 emissions as well.  Since 1970, GDP has grown at twice the rate of CO2 emissions, and 1.5x the rate of energy use. Source: World Bank.

Figure 12 - On a global scale, GDP is decoupling from energy use and CO2 emissions as well. Since 1970, GDP has grown at twice the rate of CO2 emissions, and 1.5x the rate of energy use. Source: World Bank.

Let’s be clear.  This decoupling isn’t enough yet.  Any rise in CO2 emissions per capita is problematic.  We need a steep decrease in CO2 emissions.  The above isn’t intended as a case that we’re on the right track yet – we’re not.  It’s meant to illustrate something different: In principle, it’s possible to grow wealth and well-being without using more of a physical resource.  The two can be decoupled.  Now we need to accelerate the pace of that decoupling.

Turning the Corner:

In some cases, we’ve actually gone beyond leaving consumption or pollution at a flatline, and have turned a corner.  While growing an economy, we’ve shrunk the use of some resources, and the amounts of many types of pollution released.

Consider water use.   In the United States, per capita water withdrawals rose from 1900 until the 1970s.  But since then, they’ve dropped by more than a third:

Figure 13 - Water use per person in the United States peaked in the late 1970s and has declined ever since, largely due to more efficient agriculture. Source: Pacific Institute.  Background Image: José Manuel Suárez

Figure 13 - Water use per person in the United States peaked in the late 1970s and has declined ever since, largely due to more efficient agriculture. Source: Pacific Institute. Background Image: José Manuel Suárez

That drop in water use has happened even as the US economy has roughly doubled in size and as US food production (the primary use of water) has also doubled.  How?  More efficient technology.  We’ve increased crop yields by designing seeds that make better use of water and nutrients.  We’ve shifted farm irrigation towards more and more efficient drip irrigation.  We’ve increased the use of no-till farming, that dries out the soil less, conserving more of the water that’s there.

Again, this change isn’t yet enough.  But it’s an indicator that we can grow wealth and grow output while shrinking consumption.

The same is even more true in pollution.

Emissions of sulfur dioxide, the chemical that causes acid rain, are less than half of what they were in 1970, and are down to levels not seen in the United States since 1910.  Carbon monoxide emissions are down to half of what they were in 1970.  Mercury emissions have dropped by half since 1990.  Lead concentrations in the atmosphere are just one tenth of what they were in 1980, and new emissions of lead have dropped to near zero.  Emissions of particulates, PCBs, and nitrogen oxide are all down by roughly half.   Worldwide emissions of ozone-destroying CFCs, once used as refrigerants, have plummeted to nearly zero.  The Antarctic ozone hole is now recovering, ahead of schedule.

Figure 14 – The world has driven the production of ozone-destroying CFCs down nearly to zero. Source: World Bank. Background Image: NASA.

Figure 14 – The world has driven the production of ozone-destroying CFCs down nearly to zero. Source: World Bank. Background Image: NASA.

The Limits to Growth model predicted that pollution would keep increasing so long as the world economy grew.  The only way to reduce pollution was to reduce economic activity.  But that isn’t what happened.  Our cars and trucks haven’t stopped running.  Their engines haven’t seized up.  Our power plants have kept producing valuable electricity.  And our refrigerators haven’t stopped working.  In every case we’ve found a way to reduce the amount of a pollutant we emit, or to replace the substance with something more benign, without stopping industry or growth.  Innovation has driven down pollution while our economy has grown.

That hasn’t happened on its own.  The market has played a key role in each of those reductions of pollution, but it hasn’t been the driver. The driver has been our decision, collectively, to put restrictions on pollution levels.  The US created laws to phase our lead and benzene, to reduce the emissions of acid-rain producing sulfur dioxide, and to control other pollutants.  The world as a whole signed the Montreal Protocol to phase out CFCs and other compounds that were destroying the planet’s ozone layer.

Environmental concern is a phenomena that tends to rise in a nation after a certain level of wealth. Still developing nations like China haven’t reached that point yet.  Until recently, the environment has been a low priority.  But with pollution there approaching levels nearly as bad as the US saw in the 70s, we can see the beginnings of a Chinese environmental movement that will likewise press for reduced pollution.

We still have miles to go in driving pollution lower, but the successes of the last decades demonstrate that pollution isn’t an inevitable side effect of economic growth. We can have more, while polluting less, and while consuming less.

Winning the Race

So we’re at a crucial point in human history –  a race between destruction and creation.  On the one side, we have the pace at which we’re consuming finite resources and warming and polluting the planet – a trend with disastrous consequences should it continue unchecked.  On the other side, we have our vigorous progress in innovating to tap more efficiently and cleanly into a truly enormous supply of fundamental natural resources the planet provides.

Are we on track to win this race?

That’s not at all clear. Consider, for a moment, climate and energy.  Multiple groups have proposed plans by which the world could be powered almost entirely by renewable energy by 2050, or, in the most ambitions plans, by 2030.

Yet even as those plans are articulated, worldwide CO2 emissions are rising, not falling.  In 2012, the planet as a whole emitted a record-breaking 35.6 billion tons of CO2 into the atmosphere.  And the concentration of greenhouse gases in the atmosphere is surging along with our annual emissions. In 2012, atmospheric CO2 concentrations rose by the largest amount in 15 years to a new level of 395 ppm, most of the way to the 450ppm that climate scientists have articulated as the threshold for dangerous warming.

The fundamental driver here is economics.  Consumers, businesses, and industry want energy. They need energy.  That’s true everywhere in the world. And they will buy whatever sort of energy is cheapest. Indeed, if a new source of energy is sufficiently cheaper than the old, consumers will switch their energy consumption from the old to the new.

If we want to win the race against climate change, one thing matters more than all others:  make renewable energy (including storage) cheap.  Dirt cheap.  And do it fast.

How do we do that?  Fundamentally, we need to increase the pace of innovation.  And there are two clear strategies to do so.

The first is to invest more in clean energy R&D.  In 2012, the US suffered $100 billion in damage from the climate-linked disasters of Hurricane Sandy and the still-ongoing drought.  Yet we spent only $5 billion on clean energy R&D, an amount that’s roughly half of what we spent in the 1980s.  It’s also a small fraction of the $30 billion the US spends each year on medical research and the $80 billion the US spends each year on defense R&D.  Yet in a very real sense, clean energy R&D is an investment in both future health and in national security.  Bill Gates proposed last year that this amount should be roughly tripled to $16 billion.  That’s a fine start.

The second is to be more inclusive in our cost accounting.  The market is a brilliant algorithm that does a masterful job of allocating resources and driving incentives – so long as costs are fully transparent to it.  But sometimes, a cost is completely missing from the books – missing in such a way that the market can’t see it.

Fossil fuels have substantial side effects that those who burn them aren’t charged for.  The damage done to the environment – and thus, to others – is a cost that society pays, which isn’t passed on to the polluter.  That cost is high.  Peer-reviewed research suggests that every ton of CO2 emitted inflicts somewhere between $55 and $250 of damage on the environment and others.

Because that cost isn’t passed on as part of the price of fossil fuel use, the market misbehaves.  The overall cost of coal, natural gas, and oil is higher than the price paid at the pump or on the power bill.  But the part that’s missing is being inflicted on others, spread out over billions of people on the planet, and smeared out over years to come.

Those sorts of costs that handed off to third parties are called externalities.  They’re external to the transaction happening between between buyer and seller.  Because the market doesn’t see those costs, it can’t work to minimize them on its own.  The whole history of environmental regulation is one of controlling such externalities.  We’ve done that by imposing hard limits on the amount of pollution that can be produced.   We’ve also done it by charging a price for pollution – attempting to insert that externality cost back into the transaction.  That technique – a price for polluting – was a key part of both the reduction in acid-rain producing sulfur dioxide in the United States, and also in the efforts that drove down CFC emissions around the world and prevented further damage to the ozone layer.

A price on greenhouse emissions – a carbon price, if you will – would spur both conservation and innovation.  Because fossil fuel use would be higher, consumers and businesses would be incented to use less fossil fuels, to opt for higher efficiency, and to switch to lower carbon sources of energy.

But even more importantly, a carbon price would accelerate innovation in renewable energy and energy storage.  How?  More customers purchasing wind or solar power and the batteries that will go with them means more dollars going into the industry.  That allows renewable energy manufacturers to build larger factories, which get better economies of scale in producing solar panels and wind turbines.  It also provides those companies with more dollars to invest into research and development of their own.  And it makes the industry more attractive for early stage investors looking to back revolutionary new ideas in renewable energy.

By driving the cost of renewable energy down, a carbon price has a global effect – those cheaper renewable energy sources become more attractive to consumers around the world, whether their own country has a carbon price or not.

I’ve focused here primarily on climate, because it’s the threat that touches all others.  But similar approaches apply to food, to water, and to fish in the ocean.  In all of those cases, there’s room for substantially higher federal R&D –  to invest in crops that have higher yields, particularly for the developing world; to develop new low-cost ways to cut water usage in farming; and to put more sensible prices and restrictions on the over-fishing of deep ocean fish, and thus accelerate the shift to sustainable fish farming.

Easy Way or Hard Way?

Ultimately, there are two paths forward for us, the easy way and the hard way.

In the easy way, we acknowledge the evidence that we are causing real harm to our planet, leaving it worse off for future generations, and flirting with the possibility of sudden and dramatic consequences.   We retain our optimism, that we can both address these problems and be far richer in the future than we are today.  We take our wildly successful economic system and we fix it so that it recognizes the value of our shared resources and encourages their protection, restoration, and careful, efficient, sustainable use.  We invest in action to reduce the risk of even worse future disasters caused by our unwise past.  Nothing is certain in life. But on that path, the most likely outcome is that we’ll solve the problems that plague us and grow progressively richer even as we reduce and eventually reverse our negative impact on the planet.

On this path, there’s no sign that economic growth needs to end.  There’s no sign that we’re anywhere near the wealth limit of this planet.  We have sufficient energy, sufficient water, and the capacity to grow sufficient food to provide 9 or 10 billion people with a level of affluence far beyond what even the richest in the world enjoy today.

The other path, the hard way, isn’t so pleasant.   On that path, we continue to deny the damage we’re doing, the very real consequences, and the risk of much worse if we continue along this path.  We keep on acting in the way we have, pumping carbon into the atmosphere, warming the planet, acidifying the oceans, hunting fish towards the brink of extinction, depleting the last fossil water buried under our lands.   On that path, we’ll eventually come to realize that we’ve made a mistake.  When the rivers and wells run dry, when we can no longer find the type of fish we used to eat, when the corals we used to admire have all bleached, when droughts and floods and storms wreck our cities and fields, then we’ll realize that we’ve taken the wrong path.

And then we’ll respond.

I’m an optimist.  I believe in humanity’s ingenuity.  Even on the path of the hard way, I think we’ll prevail.  We’ll scramble and find solutions.   Yet the cost will be far higher a decade or two from now than it would be if we started today.   And the scars will run deeper, in species lost, in acidified seas, in forests chopped or burned down, in climate-created famines and pestilence, in wars and conflicts born of resource scarcity.

Or perhaps I’m wrong, and on that hard path we simply won’t respond in time, in the way that other cultures of the past failed to respond to the disasters that ultimately led to their collapse.  It’s not a chance any of us should be eager to take.

Easy way or hard way.  The choice is ours.

For more elaboration on the argument above, see The Infinite Resource: The Power of Ideas on a Finite Planet.


References and Further Reading

A long list of citations for both parts of this series is available in the references to book, from which the series is adapted.

Many of the references listed in Part One are just as relevant for understanding the solutions to our problems as the problems themselves.

To these, some good additions are below:

On the potential of renewable energy (including solar) to power the world, see:

On desalination technology past and future trends, an excellent summary is found in Menachem and Elimelech, “The Future of Seawater Desalination”, Science (2011)

On fresh water depletion: Pacific Institute, The Worlds Water, Vol. 7

On climate change: Intergovernmental Panel on Climate Change, IPCC Fourth Assessment Report: Climate Change 2007 (AR4)

On feeding the world and the ultimate limits of global food yields, see:

Data on population growth rates and on GDP, energy use, and CO2 emissions per capita are all drawn from the World Bank, Data Bank of Development Indicators

Much more is found within the book.


Ramez Naam About the Author: Ramez Naam is a computer scientist and award-winning author. He believes innovation can save the planet and lift billions into prosperity, but only if we make the right choices to embrace it. His next non-fiction book, The Infinite Resource: The Power of Ideas on a Finite Planet, lays out the path to harnessing innovation to maximize our odds of overcoming climate change, finite fossil fuels, and the host of other environmental and natural resource challenges that face us. He blogs at Follow on Twitter @ramez.

The views expressed are those of the author and are not necessarily those of Scientific American.

Comments 29 Comments

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  1. 1. jsweck 10:08 am 04/18/2013

    I agree that in the near term we need to get along with our own biological ecosystem. However, in the long run our culture will destroy this world if we don’t decouple ourselves. There is a long-term solution that also has vast payoffs in energy consumption, world creation, immortality, workable interstellar teleportation, etc.

    The solution is to use software technology and build artificial universes (like The Matrix, sans the meat). Even with today’s limited computing resources, game worlds are made entirely using software. These artificial universes are easy to make, easy to maintain, easy to change, and can hold all of our civilization (including us) inside a set of computer systems. These computers can exist anywhere – even comprising a galactic civilization if you like. Our culture will no longer be limited by biological systems. Civilization is not necessarily about building structures with physics particles – what you really need is a pool of information. Software is such a pool of information. Software, not physics, not chemistry, not electronics, and not biology, will supply most of the structures we need. With software we can create any basic science we desire (including many magical things).

    There is no need to cart biologicals all over the galaxy. Once the system is setup, you can easily teleport your immortal software self to anywhere in the galaxy. This software civilization is our future.

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  2. 2. Realist1953 10:24 am 04/18/2013

    I am Not as optimistic – while USA has passed many laws to reduce pollution, there is now an aver bigger ‘fight back’ because China and over “developing nations” are polluting, and USA politicians are rooted in the camp of “if they won’t then we won’t cause it COSTS MONEY and puts USA at a disadvantage.

    Further, Corporations look at these problems ONLY in “how can we make money?”, and so will continue to fight “doing the right thing” until they have nearly destroyed the environment – and THEN they will rush in with “we can fix this, we have the technology – just pay US HUGE, like 90% of everything you own, and we will get started.”

    I also think many of the projections of food and energy production increases are too optimistic, and that the methods used right now may actually be Killing us [GMO with NO federal oversight is risking wiping out things we need - like Bees to pollinate the foods].

    I read a SiFi book decades ago – on another world, humans believed that the most important resources they had was unlimited – the Mind. I fear that the Money gets in the way on this planet.

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  3. 3. sault 11:28 am 04/18/2013


    Magnificent. Parts I and II of this series bring together pretty much everything I’ve been trying to say for years.

    I agree that making polluters pay for the damages they cause is the most fair and equitable way to solve our environmental problems. However, these companies have exploited loopholes in the USA’s political system to make action on this front close to impossible. 100% public financing of elections could lower the influence of polluters on our energy policy and we could see some real progress on this front. Speech is and should be free. ANONYMOUS speech should not.

    And while we wait for action on climate change, the regulatory route is also available. Like you mentioned, SO2, mercury and other pollutant emissions are down considerably over the last several decades. Even so, the pollution that Americans are exposed to still causes a lot of harm. Numerous studies put the damages of coal power alone at between $100B and $500B annually. We should regulate dangerous pollutants a lot more closely and mandate stricter pollution control measures to bring the emissions of these toxic substances down even further. This will indirectly incorporate more of the costs of pollution into the activities that cause it.

    While I also have optimism for agriculture and food security, the industrial agriculture practiced in the USA has several major shortcomings. It leads to massive topsoil loss, pesticide / herbicide resistance leading to an “arms race” between the bugs / weeds that plague our crops and the chemicals designed to keep them in check, and is very energy-intensive. Methods like indoor farming, permaculture and other techniques offer some solutions to these problems, but it is still unclear whether we will be able to feed 9 or 10 billion people adequately, especially when we haven’t been successful in feeding 7 billion, albeit for logistical and social reasons mostly.

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  4. 4. geojellyroll 11:48 am 04/18/2013

    The world can’t be destroyed. Nature can’t be destroyed. Humans are thriving and will continue to do so.

    The issue is what will the larger and more niche ecosystems be like in 25 years or 100 years. Do we place a ‘value’ on their integrity or is that just another layer of human centrist thinking? Nature just ‘is’ and ethics are a creation of humans.

    Anyways, optimism and pessimism are human constructs. Unless one believes in some god or ‘purpose’ to Nature, evolutionn, etc. then whatever will be will have to be according to the properties of matter and energy. I agree with Carl Sagan when he said that humans don’t really matter in the scheme of things.

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  5. 5. Quantumburrito 11:54 am 04/18/2013

    geojellyroll: How many people do you think the earth can sustain if we all decide to live the lifestyle of the average North American? 10 billion? 100 billion? How many more years do you think we can thrive if we keep on using natural resources at the current or higher rate? A million years? A billion years? I am just trying to understand the logic of believing that nature cannot ever be destroyed and resources can never be exhausted no matter what we do.

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  6. 6. curiouswavefunction 12:08 pm 04/18/2013

    Excellent post; there certainly seems to be much cause for optimism in terms of the technology and possibilities for harnessing resources more efficiently. I think it’s also worth pointing out that GHG emissions are down by 6% or so in the last five years, mainly because of an increasing shift toward natural gas. And it’s also worth noting the promising future of nuclear energy in the form of small, modular reactors which you describe in your book.

    However I am much more skeptical about the political will, level playing field and sense of purpose that’s required to develop and implement these innovations and make them accessible to the 99%. I don’t think technology is going to be the bottleneck, the lack of consensus and determination may very well be the real deal breakers.

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  7. 7. geojellyroll 12:37 pm 04/18/2013

    Quantum: “I am just trying to understand the logic of believing that nature cannot ever be destroyed and resources can never be exhausted no matter what we do.”

    How do you destroy Nature? All we can do is alter ecosystems. Nature goes on regardless. There isn’t less organic activity today than 50 years ago or 1000 years ago. Humans are irrelevent to existence or not of Nature. The only feasible way we know Nature could be destroyed is if there was a nearby Super Nova explosion that sterilized the Earth…and there are no candidates for that.

    As for ‘resources’. As a geologist I never understand the ‘running out’. We barely scratch the resources we have and, when they are no longer viable, we use others. What exactly are we going to run out of that we can’t be innovative and adapt to? Humans can live and breed in the Kalhari desert and we can live and breed in Mexico City. We are incredibly versatile.

    bottom line…the arguments for saving ecosystems to save humanity is a dead end. A billion Chinese and billion Indians need never experience an acre of natural anything. They live just fine. What you call Nature won’t be ‘saved’ because of any dire issues for humanity but because of a value we put on the integrity of the natural world.

    All those speeches given in high school about how ‘we must save the pandas or we will be next’ were wrong. Humans can thrive quite find and in fact, one day may do so in space.

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  8. 8. OgreMk5 1:26 pm 04/18/2013

    Whether I’m optimistic or not depends on the day and what I just read. In some ways, yes. I’m building a new house. It will be nearly twice as large as the house I’m in now, but is projected to use less electricity.

    General Electric claims that if every business in the world switched to their new tube LEDs, global power consumption would be reduced by 7%. I don’t know how accurate that it, but it’s an interesting claim.

    Personally, I think that the developing countries will be the biggest drivers for clean energy and these renewable systems than the developed countries. A small community in the China mountains or the African desert can’t build a coal-fired power plant, but they can build a solar power station. They probably can’t build a well to deep ground water, but they could use membranes to clean waste water for drip irrigation.

    At the same time, EV purchasing is increasing in developed countries.

    Maybe we do have a chance… but we have to get the truth of the matter and the facts to the general public all over the world. Not let the coal-CEOs control the discussion. Yes, coal with carbon capture is clean-ish. But no industrial sized carbon capture system is in place yet and ‘clean’ coal with CCS is way more expensive per megawatt than wind, natural gas, nuclear, etc. IIRC only solar PV and geothermal are more expensive than coal with CCS.

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  9. 9. jtdwyer 2:41 pm 04/18/2013

    There is no easy way!

    Why should our objective be to produce 70% more food to feed an expected 30% more people? Why should we allow ourselves to impose an additional 2 billion people on this planet? That we are considering the subjects discussed in these two articles is a result of our having already exceeded the Planet’s carrying capacity!

    History indicates that increasing food supply will result in the expansion of our population. We must find some effective method of managing humanity’s existence, or suffer the consequences. The fundamental problem is that our population has increased more than seven-fold since the industrial revolution two hundred years ago – it’s now far larger than at any other time in the history of the Earth. This not ‘the new normal’…

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  10. 10. Kewaynes 3:11 pm 04/18/2013

    There are encouraging things and optimism to be gained from this article if the statistics are accurate. But I think that innovation needs to be coupled with reduction in consumption and living simpler, happier lives.

    For instance, it said the there needs to be over 300 gallons of water a day used to sustain the average person while in America it’s 900 gallons. And food demand will go up mainly because of meat demand (because everyone will want to consume like the western world). Why can’t we ever talk about reducing consumption.

    I’m no geologist and don’t know extensively about resources but I have read plenty where of articles where scientists say that for everyone in the world to live like and American we would need 3 or 4 more Earths.

    And, to say that all those Chinese and Indians are living ‘fine’ without anything ever being natural seems funny to me. You try it.

    Last point. Countless studies show that beyond a certain point, gdp per capita has diminishing returns for human well-being and happiness and can even have negative affects. I don’t think you have to look much farther than all the unhappiness in America that is caused by consumerism and materialism.

    So, I do agree that the innovation is awesome but I belive more so that we need to change the way we live and live simpler, and happier, lives.

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  11. 11. syzygyygyzys 4:04 pm 04/18/2013

    What this two-part article boils down to is:

    We will figure it out. Don’t worry.

    And I think the author is basically right.

    I’m building a small manufacturing plant that will generate renewable energy for sale while we make product. True it’s only a modest step in the right direction, but at least I’m not camping on the internet all day just yapping. (And No, I’m not saying that means my opinions are superior to anyone else.)

    Think about how much all the ad hominem attacks (name calling) and rants are contributing to these environmental blogs (I don’t see all of the frequent flyers here yet, but they will find this one soon.) The rancor and even profanity directed at each other likely drives away people who may be looking for a serious discussion. It’s not for me to question the sincerity of your individual beliefs. And I don’t claim superior knowledge or insight on these topics. I just have some practical experience in a small segment of renewables and many years of building and operating factories.

    So, think about spending some time away from your computer to implement some of what you preach. When you come here to make comments, try doing it with civility. You many reach a wider audience that way.

    Anyone who believes they have all the answers should reconsider that position. I’m still working to understand some of the questions.

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  12. 12. sault 4:08 pm 04/18/2013


    First of all, you’re misdirecting this debate into a dead-end philisophical exchange. We need to focus on the fact that disrupting ecosystems causes real damage to people’s health and well being. People rely on the “ecosystem services” that nature provides, like water filtration, crop pollenation, etc. When natural processes are degraded, these services are diminished or dissappear entirely. Since we chop down forests, pollute the Earth and overharvest resources in pursuit of profit, the damages these activities and their associated price tags make this an economic discussion, not a philosophical one. Spending $1 cleaning up toxic waste so that the people who generated that toxic waste can pocket $1 is a fairly bad deal for everyone else.

    Sure, if humanity goes extinct, nature would bury most of the evidence of our existance in a geologic blink of an eye. However, that doesn’t mean we shouldn’t try to see how we can do things better. If we subscribe to your fatalistic view, then we lock in unnecessary suffering for countless generations of people that will follow us. So why should we just wait for disaster to strike and wipe out a lot of what we’ve been working for over the years? We burn fossil fuels to make our lives easier. But if dealing with the consequences of fossil fuel pollution starts making our lives harder and harder, isn’t that kind of pointless?

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  13. 13. geojellyroll 4:15 pm 04/18/2013

    Kewaynes..your definition of happiness is somewhat narrow. The world is not the US. I first went to China in the early 1980′s and then again 4 years ago. It’s easy to say materialism doesn’t increase happiness when you already have ‘stuff’ like a television, soft bed, car, and a variety of food choices. The medicrity of life in Chengdu was once so apparent but last time I was there the discussion was about the latest cell phone features. Young people there are ambitious and forward thinking.

    As for resources. No, we don’t need 4 Earths. Few resources have barely been scratched. The exception is petroleum. Coal reserves, metals, etc. are exploited or not based on economic viability.

    We are not going to preserve ecosystems based on some false fear that humanity is going to perish. The Chinese, Inians, Indonesians, Brazilians would say that they are doing quite well and are quite optimistic.

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  14. 14. jtdwyer 8:59 pm 04/18/2013

    geojellyroll – “The Chinese, Indians, Indonesians, Brazilians would say that they are doing quite well and are quite optimistic.”

    The Chinese are now the world’s greatest polluters, and India will soon overtake China as the most populaced country. While both countries are improving the lives of many of their citizens, many more remain in misery. When you ask Chinese administrators whether they are meeting their objectives, they also seem to reply ‘yes’. Don’t worry – be happy!

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  15. 15. N a g n o s t i c 12:28 am 04/19/2013

    Human industrial activity has resulted in an overall and drastic improvement in human circumstances. That’s what the author observes, just by looking at the plain facts.

    200 years of agricultural progress happened in spite of Malthus. It happened because people like to make money.
    Should energy production and storage technologies progress along Green lines, it’ll be for the same reason – money. It certainly won’t be for tomorrow’s children or today’s chicken littles.

    We’ll be alright, until the next asteroid or mega-volcano puts our current, silly concerns in proper perspective.

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  16. 16. N a g n o s t i c 1:47 am 04/19/2013

    One thing the misanthropic, Earth-worshipping leftist (MEWL) types will never admit is how counter-productive they’ve been over the years, in regards to today’s energy climate.

    The MEWLs helped squelch nuclear power progress and they actively encourage the obliteration of hydro-power – so we still burn coal. The MEWL’s misanthropic population alarmism and predictions of a coming ice-age did not bear fruit. They refuse to admit their lousy predictive powers, then they jump on the global-warming bandwagon. They already hate capitalism, so there’ll be no solutions from them.

    No wonder there’s AGW Deniers. Foolish they are, but they’re just responding to the unhelpful MEWLs and their pre-existing, anti-capitalist agenda.

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  17. 17. sofistek 7:53 pm 04/19/2013

    Infinite growth on a finite planet isn’t possible. That’s so obviously true that it’s incredible any sane person would argue with it. The only counter would be, yes but humans will go extinct long before any critical resource runs out. That is wishful thinking. We may have only scratched the theoretical surface of the resources that are buried in the planet but the vast majority of them are unreachable for all practical purposes. Resources other than oil and other fossil fuels, require energy for extraction and processing. So energy is the critical resource. If one can keep ramping up the energy available, then more resource becomes available but one can’t keep doing that. There comes a point when extracting additional energy requires more energy input. Some fossil fuel sources are starting to head that way now. So it’s pointless to suggest that there are huge amounts of resources available to us. There aren’t. Once energy starts to decline, as it must, that’s the end of the road for growth in resource extraction.

    Someone mentioned substitutability. Another wishful thought. At some point we will use the best resource for the job or the one that provides adequate supplies for the job, at sufficient rates and affordable prices. Resources aren’t infinitely substitutable.

    Limits To Growth has been shown to have got the standard run fairly close, in hindsight. Yet we still try to deny the realities of living on a finite planet as the climate and almost all other aspects of our environment continue to deteriorate. Economies are subsets of the environment (though many economists think it’s the other way round), so continued degradation of the environment can’t support continued growth of economies. And we’ve seen that for the last 5 years (unless one blindly accepts the GDP figures that governments have manipulated).

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  18. 18. TobyinSeattle 10:29 pm 04/19/2013

    Nagnostic @16: There are many cogent analysts who think that capitalism, that paragon of psychopathological systems (i.e., utterly focused on I-it and not I-you relationships, to use Buber terminology), cannot survive peak oil and other systems problems created by its growth-uber-alles paradigm. Markets work great for some things like technological innovation, but if they are not controlled, you get the extremes of wealth inequity and externalities (global warming, anyone?) that we’re experiencing today.

    Maybe I’m too pessimistic, but I find the author and a number of commenters (like geojellyroll–an engineer of course) to be overly optimistic. Technology by itself is not going to “save us” from our population overshoot. The energy problem can be solved, but only if we realize that the current level of consumption is not sustainable. Not even close.

    It’s not just oil that we are clearly at if not past peak, it’s also natural gas–a primary source of fertilizer–and coal is just a few decades out at current projected rates of use (assuming the externality of global warming doesn’t snuff the economy that needs to burn it first). And phosphorus, another key element for industrial agriculture. This magazine has published articles on “planetary boundaries” before (; they are real.

    I think the best outcome we can expect is that people will be able to recreate decent economies at more local and regional scales as fossil fuel gets increasingly expensive. As Jeff Rubin’s book is titled, “Why Your World Is About to Get a Whole Lot Smaller: Oil and the End of Globalization”. Remember EROI (“net energy”) when calculating the utility of any energy source–none of the “green” ones come close to either the capacity or EROI of the first half of the Age of Oil.

    BTW, Nagnostic @16, you need to read syzygyygyzys @11 and please stop posting angry name-calling garbage. “MEWLs” didn’t kill nuclear power–nuclear power killed itself because it’s too expensive and dangerous. And it’s also subject to EROI and fuel supply limitations.

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  19. 19. TobyinSeattle 10:35 pm 04/19/2013

    P.s. I forgot to give credit to sofistek @17 who described EROI in everything but name. That post is excellent.

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  20. 20. Dr. Strangelove 3:05 am 04/22/2013

    I disagree with your solution of growing the pie. The pie is big enough. The world produces enough food to make everyone on earth obese. Why some people still hungry? Because they can’t afford it.

    7 billion people cannot possibly consume all the water in the ocean. Desalination costs 500 gallons per dollar. If you can afford that, the supply is unlimited. Why some people still no clean water? Because they can’t afford it.

    If you put 150 sq.m. of solar panels on your roof and 200 kg of battery to store electricity, that’s enough to power a modest home indefinitely. Why aren’t people doing it? Because it’s cheaper to buy from the grid.

    Some people are getting most of the pie and some aren’t getting enough because they can’t afford or don’t want to pay. Is that a problem of supply or economics?

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  21. 21. OgreMk5 10:23 am 04/22/2013

    Another interesting point is that technology is decreasing the need for raw materials needed to build stuff.

    I have, in my pocket, a device that weighs less than 5 ounces. It functions as a watch, computer, phone, video/still camera, flashlight, network router, music player, television, video game system, note pad, calendar book, etc. etc. etc.

    It’s a pretty darn efficient use of resources. Five ounces instead of 50 pounds of equipment that would have been required in 1990. Stick a projector on it and add a flexible keyboard and I would be perfectly happy with my phone as my sole device.

    The reason we have such powerful cell phones is that people want them. They have become required in today’s world. Soon, I hope, clean electricity and water will be under the same economic pressure. Then we’ll see some advancement.

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  22. 22. Heteromeles 11:34 am 04/25/2013

    Nontrivial and fundamental ecosystem science point: you lose about 90% between trophic levels. Therefore, if an acre of grain can convert 13% of sunlight into calories, the maximum we should expect to get out of that field is 1.3% of the sunlight, not “say, 3%.” You don’t get to make up the numbers here.

    Second problem is that we’ve externalized the cost of turning that 1.3% into food by using fossil sunlight (aka fossil fuels) and even then, we only get 0.1% efficiency. That’s a non-trivial warning there that ramping it up is even harder than we might think.

    Second huge problem is talking about the US in a globalized economy. Yes, the US has made enormous strides in cutting its own pollution. Unfortunately, we’ve done this by offshoring our pollution, as much as by getting rid of it. Have you seen the air pollution in China? A lot of that comes from production for our markets. Similarly, we can brag about getting rid of DDT, but it’s still used outside our country, and when we import food, we still ingest DDT.

    I’m not so sanguine about the future, but oddly, it’s for a different reason. Despite the negativity of the first two paragraphs, I agree that there’s no technological reason we can’t make sure everyone has enough food and access to clean water. Unfortunately, there are huge political reasons why this won’t happen, relating to things like greed, corruption, violence, and good old-fashioned envy. Translating this to modern terms, this is: consumerism (people wanting to get and stay rich at any cost), corruption (see Wall Street, Shanghai, Washington DC, etc), violence (see the military-industrial complex), and envy (see the rest of the world wanting to match US levels of consumption, on the mistaken notion that they’ll be happier if they get there).

    Right now, we’re demonstrating a horrible lack of innovation in political problem solving on every level. Technology can’t save us if we’re unwilling to commit to the social changes needed to make it work. I’d suggest that anyone who suggests a technical fix is trying to take the easy way out. The hard problems right now are in politics, not science.

    Ultimately, this may be our epitaph: we could have solved all our problems, but we couldn’t bring ourselves to do so. Fortunately, I’m pretty sure the human species will survive, whatever we do. I’d love to have a better memorial than that. Wouldn’t you?

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  23. 23. David Schwartzman 1:42 pm 05/9/2013

    Bravo Ramez Naam! It is very refreshing to read an optimistic and well-informed take on the alleged limits of the Earth, with his arguments for renewable energy and more ecologically friendly agriculture. The limits to growth advocates fail to distinguish between the qualitative differences of growth in the physical economy while invoking the usual neo-Malthusian population explanation of our deepening crises. Naam deconstructs the latter argument quite well. However, while recognizing the climate tipping points, he does not confront the ever diminishing window of opportunity to implement an effective program to avoid climate catastrophe, and leaves us without any sense of how we could reach the political tipping point for such implementation before the climate tipping points are reached. His prescription ignores the huge obstacles that have to be overcome in time, arguing for a putting a price on carbon and boosting investments in renewable energy, without discussing the push back from the political economy of capitalism with the Military Industrial (Fossil Fuels, Nuclear, State Terror) Complex at its core. A Global Green New Deal is imperative, demilitarize, solarize and prioritize agroecologies replacing industrial and GMO agriculture. For more:

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  24. 24. David Schwartzman 5:25 pm 05/9/2013

    P.S. Yes we need a transformation of agriculture, but I strongly disagree with Naam’s support for GMO as the alternative more capable of feeding a growing global population. GMO development is driven by profit hungry transnational corporations, such as Monsanto. Urban organic gardening and agroecology are the real alternatives to industrial agriculture, not GMO crops. Agroecology is a work in progress drawing from the wisdom of pre-industrial peasant agriculture and the cutting edge sciences of ecology and molecular biology. This is the advanced agriculture, not GMO with its serious social, ecological, health and nutritional threats, now increasingly documented in peer-reviewed literature. For documentation on the health and environmental risks of GMO crops/food go to:,,,,

    Agroecologies are fully capable of feeding our present population, even a projected 9 billion, at the highest nutritional level, without the huge negative impacts of present agriculture. Agroecology/organic agriculture is now blossoming, with remarkable initiatives in many countries, especially Cuba (Funes et al., 2002). There is growing evidence that this mode of agricultural production can replace the unsustainable green revolution stage of industrial agriculture, now being transformed by the use of genetically modified organisms, abandoning traditional crop and animal breeding. Further agroecology has the potential of feeding humanity without the negative health, ecological and environmental impacts of the present mode (e.g., Badgley et al., 2007, Perfecto et al., 2009, Agroecology in Action, Koohafkan et al., 2011).

    References cited:
    Agroecology in Action.
    Badgley, Catherine, Jeremy Moghtader, Eileen Quintero, Emily Zakem, M. Jahi Chappell, Katia Aviles-Vazquez, Andrea Samulon, and Ivette Perfecto. 2007. Organic Agriculture and the Global Food Supply. Renewable Agriculture and Food Systems 22, 86-108.
    Koohafkan, Parviz , Miguel A. Altieri and Eric Holt Gimenez. 2011. Green Agriculture: foundations for biodiverse, resilient and productive agricultural systems. International Journal of Agricultural Sustainability. Available at:

    Perfecto, Ivette, Vandermeer, John and Wright, Angus, 2009. Nature’s Matrix. Linking Agriculture, Conservation and Food Sovereignty. London: Earthscan.

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  25. 25. antonalfredo 12:30 pm 05/13/2013

    Unfortunately, in capitalism resources that aren’t used are considered costs.

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  26. 26. peakoilproof 2:28 pm 05/24/2013

    Rebuttal: google “The Core Peak Oil Debate: Speed and Scale”

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  27. 27. alexkatovsky 8:47 pm 06/21/2013

    Your time series showing US GDP and energy use reminded me of the growing gap seen in the US since about 1970 between productivity and labour compensation ( Maybe there’s no link between the two; or maybe GDP is a bad measure of the health of an economy, and the trend in energy use in the US is reflecting economic malaise?

    Link to this
  28. 28. marino 4:02 am 07/31/2013

    All is and will always be A.E.I.O.U or Absolute Energy = Input, Output, Utilisation.
    Humans are just a form of this and are just “human energy slaves”, a cause, for one effect or another.

    Link to this
  29. 29. marino 4:05 am 07/31/2013

    I forgot to add, the we are all A.E.I.O.U for A.E.I.O.U.

    Link to this

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