Water, food or energy: we won’t lack them

The world is full of problems. Pollution is a problem. The destruction of the coral reefs, the eradication of the rain forests, the mass extinction of animal species are problems, and tragedies. Loss of biodiversity is a problem. Global warming is a problem. Poverty and the unequal distribution of resources are major problems.

But lack of basic resources isn’t a problem. We’ll have enough food, water and energy for the whole human race for the forseable future, at reasonable costs. Take a worse-case scenario for all three areas, and let’s look at the figures.

First of all, water. Most of the world’s water is sea water, dwarfing the minute proportion of usable freshwater. A worse-case scenario has us having to extract all our water from the sea, using desalination. Desalination currently costs about $2 per thousand gallons, which in real units, is about $0.5 per thousand liters. It’s hard to get good recent data on water consumption, but it seems to have been 4000 cubic kilometers per year in 2003. Let’s guess it’s around 4500 cubic kilometers nowadays (about 70% of this is agricultural). It would cost about 2 trillion dollars to produce this water from desalination.

Now let’s look at food. The ultimate way of producing food would be through hydroponics or aeroponics, which grow plants in greenhouses without soil and with minimal use of nutrients and pesticides. The water use is greatly reduced, and a lot of it can be recycled, so the running and resource costs of hydroponics are below what we spend on agriculture today, leaving only the capital costs to be estimated. Numbers on hydroponics are hard to come by, but some charities claim hydroponics as a viable method of small scale food production, one estimating the cost of setting up a sustainable hydroponic garden for a family of four at $355. To feed seven billion people that way would cost 0.6 trillion dollars. This gives an approximate estimate, but we can also use market arguments: there currently are well-established large scale hydroponic farms, and their products appear to be competitive. Agriculture represents about 6% of world GDP, or about 3.6 trillion dollars. A quarter (1.5%of world GDP) of that is meat, which we’ll ignore for the moment. We can thus get a second estimate that feeding the world through hydroponics would cost about as much as current agricultural plant output, or about 2.7 trillion dollars. Let’s double this to be sure, to say 5.4 trillion. Meat itself should become possible to be grown in-vitro soon; apart from the great increase in humaneness, this will also mean a huge decrease in the water and other resources needed.

Where does this leave us? Agriculture currently uses 3.6 trillion dollars per year. Producing, through desalination, all the water we now use would cost 2 trillion dollars, while producing our food through hydroponics would cost between 0.6 trillion to 5.4 trillion dollars – but would need a lot less water. So it seems that to produce all our food and water “artificially” would cost roughly the same our current agriculture. The technologies we’d need to use are existent, but underdeveloped: so we would expect these costs to diminish as demand for them increased.

Now the big one, energy. Let’s restrict ourselves only to solar power and already built hydroelectricity. Solar seems to cost about $7 per Watt. World energy consumption was about 15 Terawatts (TW) in 2008. Round that up to 16 TW for 2011, and take off 1TW for the (already built) hydroelectric capacity.  So installing enough solar panels to power the world would cost about 141 trillion dollars. The costs go down at about 6% per year, relatively stably, which means costs halve every 12 years. Were solar power to be rolled out on a huge scale, these costs would likely drop further.

Solar panels must be maintained and replaced; current manufacturers seem to guarantee that their panels will last, with 80% efficiency, for 25 years. So we will need to spend 141*5/4=176 trillion dollars over 25 years, or 7 trillion dollars a year. Current world GDP is around 63 trillion dollars, of which about 10% is spent directly on energy, or 6.3 trillion dollars a year.

So it seems we could replace our energy sources with solar panels, at current prices, while spending only a tiny bit more than we currently do. As the prices drop, this would be less than what we currently do. Nor do we have to worry about higher GDP growth resulting in higher energy needs: world energy intensity (energy per unit of GDP) is falling in western countries and stable elsewhere, so the percentage of GDP dedicated to energy generation wouldn’t change. There are, of course, storage, transmission and maintenance costs; but current energy methods also have indirect costs and subsidies above the 10% mentioned above, which should be comparable.

So the costs of using completely sustainable food, water and energy are comparable to the costs we currently pay for them. And these technologies already exist; so if energy costs rise, or environmental depletions do the same to food and water costs, economics will push towards adopting these alternatives.

The world has a lot of problems, but lack of basic resources isn’t one of them.

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5 Responses to Water, food or energy: we won’t lack them

  • Simon Jm says:

    Stuart do you think the Club of Rome work -which has been updated and found to be pretty well on the money- is flawed? & what about energy with Peak Oil which even the Pentagon and establisment players like Llyods Of London accept?

    Then we have the high energy requirements of desal -though I haver heard about the solar desal- you often have brine pollution severely impacting the local ecosystem. There are also many who are now arguing that renewables wont be much help cause we are now running into Peak Oil and the transition to renewables requires cheap fossil fuels let alone a healthy economy.

    BTW you don't happen to be a Transhumanist do you?

    From what I'm reading worst case scenarios are starvation, riots and wars.

    • Stuart Armstrong says:

      >do you think the Club of Rome work -which has been updated and found to be pretty well on the money- is flawed?

      Solar power is a true renewable, so is not a finite resource in the sense of the "limits to growth" (at least until the planet is completely covered in panels, which is a long, long, long way off). Ditto, in all practical senses, for sea water.

      >what about energy with Peak Oil which even the Pentagon and establisment players like Llyods Of London accept?

      Peak oil would be better to have sooner, rather than later, because of global warming. World energy consumption includes oil. So there does need to be an extra step: transforming the energy we need from the sun into a format that our transport system can use, such as fuel cells. There would need to be adjustments to change over our infrastructure, and this may be disruptive – but as challenges go, this isn’t the big one, since we’d already have the energy we need.

      >Then we have the high energy requirements of desal

      This webpage gives the energy requirements for desal: http://www.desware.net/desa4.aspx . I’ll take the lowest figure, since if energy is scarce, energy efficiency will be the most important part of the cost. This is around 2kWh per cubic meter. 4500 cubic kilometers of water contain 4.5 trillion cubic meters, so we’d need about 9 trillion kWh in a year. There are about 9000 hours in a year, so we’d need a billion kW, or 1 terawatt. This would increase energy requirements from 15TW to 16TW, or about 7%. So this is not a large extra burden.

      >you often have brine pollution severely impacting the local ecosystem.

      Hey, I didn’t say these solutions would be nice, just that they’re there.

      >BTW you don’t happen to be a Transhumanist do you?

      Not really. They have some sensible things to say about avoiding death and permitting dramatic human flourishing, but they are far too enamoured with technology.

    • The Club of Rome has not been right on the money. Many seem to think that fitting data to its curves will tell them anything, ignoring strong statistical and forecasting problems.

      The main flaw of the classic Limits to Growth predictions (beside the very problematic model itself) was that they left out technological improvement, which really does matter. Looking at the Santa Fe Institute performance curve database http://pcdb.santafe.edu/ and related papers shows that generic behaviour of technologies is that the number of units per dollar decreases exponentially with time – usually not as dramatic as Moore's law in electronics, but still significant from a resource perspective. This is of course no reason for complacency since that improvement can be too slow to meet increasing demands, but it shows that resource limits are time dependent. And it might well be that this dependency can be changed by changing demands (the relation between energy use and GDP per capita did an impressive turn in the early 70s – http://www.aleph.se/andart/archives/images/fig2007userg.html )

      As for worst case scenarios, a bit of global starvation and war seems positively benign compared to some of the possibilities Stuart and me tend to discuss at FHI. A resource starved world is a bad outcome, but our worst case scenarios are much worse. It is in the tails of the probability distribution where the real risk hides.

  • Simon Jm says:

    Stuart
    >Solar power is a true renewable, so is not a finite resource in the sense of the "limits to growth" (at least until the planet is completely covered in panels, which is a long, long, long way off). Ditto, in all practical senses, for sea water.

    True but you have to have an underlying functional economy and finances to do this and you won’t achieve that transition if other resources esp energy are declining in such a way to make a transition impossible.

    > Peak oil would be better to have sooner, rather than later, because of global warming.

    I agree to some extent, it may even head off the worst case scenarios,

    >World energy consumption includes oil. So there does need to be an extra step: transforming the energy we need from the sun into a format that our transport system can use, such as fuel cells. There would need to be adjustments to change over our infrastructure, and this may be disruptive
    – but as challenges go, this isn’t the big one, since we’d already have the energy we need.

    but again the infrastructure and finance needed to do it isn’t likely to be there to have a renewable high tech future. Some of the guys crunching the numbers think we would need a 15year transition period when we still had cheap energy to do it. Unfortunately we have squandered that and will be heading into economic, energy and financial contraction. With due respect -while no expert myself- the centrality of cheap oil in the global economy cannot be emphasised enough, without it our current economic system won’t function in a way that will provide for business as usual let alone the transition to renewables.

    >This webpage gives the energy requirements for desal: http://www.desware.net/desa4.aspx . I’ll take the lowest figure, since if energy is scarce, energy efficiency will be the most important part of the cost. This is around 2kWh per cubic meter. 4500 cubic kilometers of water contain 4.5 trillion cubic meters, so we’d need about 9 trillion kWh in a year. There are about 9000 hours in a year, so we’d need a billion kW, or 1 terawatt. This would increase energy requirements from 15TW to 16TW, or about 7%. So this is not a large extra burden.

    I’ve seen higher figures but let’s take it for granted that yours are the best available figures. First when you need energy for other things growing as well during a time when where there is less cheap energy –or credit- available what seems small is actually quite significant apart from the fact not everyone will be living within easy reach of the plants and from the wiki desal page its pointed out, it takes quite a bit of energy to pump water long distances. Then factor in pumping dry of aquifers you would have to replace and it starts add up. I also imagine the effort involved to convert to aquaculture is like renewables imagine getting the millions of Indian and Chinese farmers -let alone the rest of the world to transition when you are having food and water shortages. Extremely difficult during perfect concidtions let alone what we face.

    >Hey, I didn’t say these solutions would be nice, just that they’re there.

    Granted you didn’t, I did though take it for granted we would want some sort of solution that was sustainable and didn’t cause other major problems otherwise those costs should then also be put on the desal cost.

    >>BTW you don’t happen to be a Transhumanist do you?
    >Not really. They have some sensible things to say about avoiding death and permitting dramatic human flourishing, but they are far too enamoured with technology.

    Agree 100% there :)

  • Simon Jm says:

    Anders I’ll do my best as a lay person

    First I don’t know if it’s just about statistics I keep an avid interest in general science and environmental matters and it would seem across the board natural capital continues to be depleted. This is certainly in line with that recent planetary boundaries work. I’m not sure you are raising the they are just models argument, regardless natural capital continues to be depleted at a unsustainable rate so unless you have some spare earths some where the Club of Rome scenario ranges does seem to be one the money.

    I’d also imagine someone like Tainter would then point out things like drop in patents developed over time and diminishing returns from complexity, that sure that for a time under certain conditions the units per dollar will decrease but that is linked to certain very specific conditions that simply won’t be there for it to continue. & we might had impressive changes during the 70’s but I’m not sure we would have continued to do so with the structural, energy and likely deflationary credit problems we are facing now. Certainly you are not going to get an environment friendly to innovation for solving these problems the GOP won’t even acknowledge climate change let alone resource issues.

    BTW worst case scenarios I’ve read sees about 3-4billion people dying from the end of global oil based industrial agriculture, that and the sort of global instability that would arise from that sort of situation we might find that putting solar thermal power stations in the Sahara might be just a bit problematic. Or that even a limited nuclear exchange between India and Pakistan over say water issues would cause a decade long nuclear winter. One could think that the 4billion dead would be exceeded under those circumstances.

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