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.