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Chickpea Earth

Note: this is a long, rambling entry that swings from naval gazing to some interesting stuff on global energy futures.


There's a gymball in my bedroom: silver, 800mm wide. Having stared at it for a while, I started to wonder - if the sun were that gymball, how big would the Earth be? A few sums later I got 7mm. Some frantic measuring of dried pulses followed, and a chickpea emerged as the perfect - if slightly lumpy - candidate for sitting on the floor next to the gymball. There it sits still, so every night I can stare at it and mutter to myself, 'that's just stupid.' I include a photo of chickpea on gymball. But photos, this description - they don't do it justice. Find a gymball of equal size, get a chickpea: hold it between thumb and forefinger, having made sure to watch a video of the sun first. (Some would argue 'blue marble' better captures the wonder of it; each to their own.)

Incidentally, you can scale to anything you like at this website. At the scale above, chickpea would be 85 metres away from gymball.

I've also been trying to wrap my noggin around our place on Chickpea Earth. This has included an alarming assault on my sense of Earthly security, such as a list of all the ways in which we might never have existed. Some of these were covered in rather sensationalist tone by Tony Robinson's channel 4 series, 'Catastrophe Earth'. This quote sums up the general approach:

85000 years ago, humans were just heading out of Africa; the meteoric rise of our species makes us feel indestructible. Yet we are more vulnerable than we might care to imagine. We live on a thin crust that floats on a sea of pressurised molten rock and we rely on the proximity of a star to keep temperatures optimal for life. Meanwhile our planet moves through space, which is populated by numerous flying objects.

We have various protections. For instance, the Earth can deal with changes in heat from the sun through what Stephen Lansing calls system-dependent selection - the classic model being Lovelock's Daisyworld. The Oort Cloud protects us from stray asteroids (or may possibly be a source of them.) Our magnetosphere deflects much of the solar wind that would otherwise strip our atmosphere away. But here we are still: 'crawling on the planet's face, some insects called the human race, lost in time, lost in space...' (there's two minutes of Susan Sarandon and Barry Bostwick slithering about in dry ice, in a way that somehow reminds me of Kate Bush videos, wearing little more than suspenders: then there's Charles Gray making that little speechet. You've been warned.)

57 varieties

But it's the human-made brand of precarity that's most fascinating, and it comes in 57 varieties. Until recently, our several near-nuclear-holocausts were the most arresting. My new top of the vertiginous terror charts, though, comes from Tim Flannery's Weather Makers. He writes that, in 1974, three scientists - Crutzen, Rowland and Molina - explained a weird anomaly that others had put down to instrument error: the hole in the ozone layer was caused by man-made chemicals, namely CFCs. At the time, not many people took the problem seriously. He writes about the subsequent corporate obfuscation and regulatory cowardice as a climate change parable - but that's not the most scary part. Only a slight difference in cost meant CFCs were more widely used, not BFCs. Bromine is, according to Flannery, 45 times more destructive of ozone. (This site says 10 - 100 times, but the point still stands.) Flannery says:

Had humans found bromine cheaper or more convenient to use than chlorine, it is quite likely that by the time Crutzen and his colleagues made their discovery, we would all have been enduring unprecedented rates of cancer, blindness and a thousand other ailments, that our food supply would have collapsed, and that our civilisation itself was under intolerable stress. And we would have had no idea of the cause until it was too late. [p.219]

Say that again: we would have had no idea until it was too late. The ozone layer would only be 3mm thick if bought down to sea-level - this tiny layer stops the sun's UV from tearing our DNA apart. We would have had no idea until it was too late.

I'm reminded of a particularly casualty-baiting drunken teenage moment: right at the top of a tall tree in high winds, going literally out on a limb, as far as I could, swaying with two thin branches in each hand. My thought process actually included: 'God won't let me die.' There was just that moment: no cognisance of how I'd got there or where I was going. That absolute certitude may have been alcohol-and-teenage-arrogance induced, but that's exactly how we work as a species. We swing merrily about on the edge of our limits and think, 'God won't let us die.' We might not think it openly, but it sits at the foundation of our worldview. I'm now wondering whether we're able to sober up, look at the evidence and do something about it.


With that hope, I've been drawn not only to all this gubbins on precarity, but to old Carter-era thinking about the limits to growth - before Reagan declared morning in America and took the solar panels off the Whitehouse roof. (Yes, I know - I'm not American. Don't care.) Where will our energy come from? Our resources? What will get us first - running out of the stuff, or burning so much that we cook the planet?

Chickpea Earth, floating an average 85 metres away from a gymball-sized sun, is a tiny dot receiving only a sliver of the sun's output: picture a sphere whose circumference is drawn by this orbit (incidentally, this is the size - it is claimed - of the event horizon of the black hole sitting at the centre of our galaxy.) By my sums, that's 2.4 billion times more energy pouring into space than the Earth ever receives.

At some point in the future, it's not inconceivable that we'll be able to harness some of that energy. All we'd need - a small thing really - is to perfect our carbon nanotube technology and drop a cable down from space, as described in this book. My own addition is to create swarms of solar otter-droids who can gaily swim in the sun's rays and harvest them for us. (That was my hippy reaction; others have noted the sun-blocking or parabolic death-ray-making possibilities that space holds.) That would be a radical break in Earth's history: exceeding the limits of what terrestrial sunfall gives us. It's a curious hypothetical: even with practically infinite carbon-free energy, what would happen on Earth? We would still face many of the same ecological problems after all.

Alarming arithmetic

Returning to our current predicaments, I've recently watched a couple of online lectures. Nathan Lewis in 'Powering the Planet' takes a broad view of all our possible energy futures. Albert Bartlett instead talks about the alarming arithmetic of exponential growth. (Transcripts: Lewis - an older one than the realplayer presentation on the site above; Bartlett.)

Bartlett sticks to his one point: divide any rate of change into 70 and you get, roughly, it's doubling period. Here's his conclusions on population growth: if we have 1.3% growth from now on -

- the world population would reach a density of one person per square metre on the dry-land surface of the Earth in 780 years. And the mass of people would equal the mass of the Earth in 2400 years.

Which is to say, of course, that's impossible. He goes on:

Zero population growth is going to happen. Whether we debate it or not, whether we like it or not, it’s absolutely certain. People could never live at that density on the dry land surface of the earth. Therefore, today’s high birth rates will drop; today’s low death rates will rise till they have exactly the same numerical value. That will certainly be in a time short compared to 780 years.

Arithmetic doesn't tell you everything you need to know, of course - hence why Dr Bartlett misses a key point in his Malthusian enthusings, and puts education in the column of 'things that increase population'. Wrong: the best way to reduce population is to educate women globally. It's the strongest correlation in development studies (with some complications.)

Bartlett moves on to energy, using the same argument. It's a pretty problem: make whatever noises you want about future oil consumption - even at 1% production increase, that doubles every 70 years. As it is, until recently, it was growing at 7% - doubling every ten years. Now we appear to be levelling off.

How lucky do you feel?

But there's plenty more coal and gas - at least enough to make sure we cook ourselves. That's Nathan Lewis' first point, and I agree: relying on 'peak oil' to force our hand on climate change is far too passive. Germany in World War Two, he notes, ran their entire war economy on coal - and there's no reason why we won't do the same when other fossil fuels dwindle.

Lewis succinctly conveys his case for climate change. He shows the famous Vostok ice core data: over half a million years, temperature changes are correlated with carbon levels in the atmosphere. He points out that doesn't mean one causes the other - but since we know that CO2 traps reflected sunlight and causes heating, we do know that CO2 must have had a direct effect. If we do nothing, we'll be on track to produce triple the highest levels in this half-million year record. We don't know what a safe level will be. We won't know exactly from computer models - the only way we could be sure, as he says, is to 'do the experiment'. (The reliability of climate models is a topic for another post.) We do know what carbon dioxide should do in an atmosphere, and that looks a lot like what happened in the Vostok record. His simple question is:

how lucky do we feel? If you feel lucky, you stay on the track we are, and you let it happen and you hope things will work out OK.

Given that, he then has a go at covering all our possible future energy options. He starts by asking, 'where can we get the energy to sustain the lifestyles we're accustomed to?' One might respond, 'maybe we can't'. But it's a good baseline because it allows him to illustrate what resources would be needed to do it.

'The currency of the world isn't dollars, it's joules,' he tells us. He's right: the language of energy is the common tongue we need.

The currency of the world

So - joules are units of energy; watts represent the rate of energy use. It's a unit of power that can be used to compare people with power stations with cars with sunlight. One watt is one joule per second. So one watt-hour is 3600 joules. The average person moving (walking, cycling gently) is putting out about a hundred watts. It's about the same when pootling at work - someone here, for instance, recalls a temperature-controlled lab where each person had to turn off a 100 watt lightbulb on entering in order to keep a constant heat.

Over an hour, a hundred watts is 360 kilojoules or 86 Calories. Gym equipment manufacturers assume that our mechanical energy use is about 12.5% efficient; most of our fuel keeps us heated. (Note: a small-c calorie is different from a Calorie, which is actually a Kilo-calorie. Note also that Google is one's friend here - especially the Firefox toolbar. You're never more than one CTRL+K away from converting any units with a simple '360 kilojoules to Calories'.)

Average fuel efficiency of UK cars is about 38 miles per gallon. Petrol contains about 158 megajoules a gallon (and yer average car turns about 25% of that into motion.) If we were about as efficient at converting petrol to energy, a gallon could keep us going gently on that cycle, at 12 miles an hour or so, for four days solid.

(That's by my sums, which likely need checking... Wikipedia says an average car uses 25,000 watts while cruising, but even presuming 100% fuel efficiency in a 38 mpg car, that seems to come out as 21 miles an hour. Huh. Maybe the fuel's used in changing speed, not maintaining it... )

A final few watts-for-perspective numbers to throw in, bearing in mind the metric prefixes:

  • Nuclear power stations average about 1 gigawatt output. (A million kilowatts; or ten million people in the Matrix - which is why it was never a very good power-source idea, particularly because that's not even a net figure. The Machines were numpties.)
  • The average European is using about 5 or 6 kilowatts in total, according to this website.
  • Sunshine falling on the Earth amounts to 120 petawatts - or the equivalent of 120 million nuclear power plants. As Nathan Lewis notes, we currently use in a year the amount of sun energy that falls to Earth in an hour.
  • Insolation: about a thousand watts of sunlight falls on every square metre at the equator. (The solar constant minus a bit for cloud reflection.) The average for the Earth as a whole is 250 watts per m2. I'll come back to this shortly.


OK, so that's the energy perspective stuff. What does it all mean? Lewis takes us through some of the findings from a 1998 paper by Hoffert et al. (Non-subscriber copy of PDF here.)

They take some assumptions from the IPCC 1990/1992 reports and see what will have to happen with energy. The Kaya Identity is used: a slightly tortuous combination of factors, but it has the handy quality of being able to come up with a number for energy demand and carbon output from projected economic growth.

Three assumptions are built in: continued efficiency improvements, expressed as energy intensity. That is, how much energy does it take to produce a dollar of GDP? Historically, efficiency has been increasing by about 1% globally. (Though, as noted here, there are some instinctive reasons for thinking there are whack-a-mole solutions going on: it's easy to become more efficient when your GDP is coming from swapping derivatives, renting houses or sitting on your arse at a laptop, whilst China is doing all that pesky carbon-intensive 'actually making things'. Whack-a-mole solution: my new favourite phrase.)

There's also the assumption that GDP will continue to grow by somewhere between one and two percent. (The IPCC have stuck on 1.6%) Which, as just discussed, means it will double every 35 to 70 years. (Something else for another post: there may be small doors through which growth could seemingly expand forever, but do they only lead to short, dead-end corridors?)

Lastly, the model is built on population reaching 10 billion by 2010: this is clealy the most important factor. Long-term, will it stabilise at 10 billion or continue to increase? Anyway, all these three are summarised in the four joined graphs I've included here.

These can all be questioned as much as Nathan Lewis' insistence on sticking to energy levels we're used to now - but, again, it's a good a place as any to start. Lewis holds that later IPCC reports haven't changed the underlying model much, so his findings still stand: I'll believe him for now (given I don't have time or expertise for checking...)

So what does he conclude? Here are two more graphs from Hoffert to look at (marked b and c). IS92a is on both of them: this is the IPCC's 'business as usual' model, with the above assumptions on energy, GDP and population growth - but no new policy interventions. Now, bear in mind that assumption about energy efficiency: they have built in that, by 2050, energy per GDP dollar will have nearly halved. Given how long ago this was, I'm not sure where things stand today. Anyway - (b) shows total global energy requirement in terawatts. The WRE lines are Wigley, Richels and Edmonds' 'stabilization paths', showing in (b) what level of carbon-burning fuel we could use to hit a certain amount of CO2 in the atmosphere. IS92a 'Business as usual' equals 'all bets are off'. 350 parts per million was where ideally we wanted to be - that would have required emitting not one more ounce of carbon by 2050 - as shown the the 350WRE line going down to zero.

(c) takes projections of renewable and nuclear from (b) and shows how much carbon-free power we'd need to be producing to hit those different WRE targets. Not forgetting the continued rise after 2050, this graph outlines the following scenarios: to stabilise at 350ppm we would need all global energy to be carbon-free - 28 terawatts. To hit 550ppm, we'd need about 20 out of 28 terawatts carbon-free by 2050. Bear in mind global energy consumption in 2000 was 13 TW in total; in 2005 it was 16 TW.

What are our carbon levels now? Here's a handy website for that: 385 ppm. So the 350 ppm target is already out of date given that it could take hundreds of years for it to leave the atmosphere.

Frankenplants and other ways to save the planet

Lewis then takes a broad look at the ways in which this carbon-free energy target could be met. To cut a long story short: biofuels - unless we start making black 'frankenplants', better able to absorb all the light - would require a third of the Earth's surface to make 3 terawatts. And that's not a net figure - as he notes, in the US, it's 'barely break-even' and currently the inputs are largely fossil fuels. Duh. He covers hydro, wind power, various other forms of biomass and types of solar.

But it's solar power that animates him - unsurprisingly, since his team is working to mimic plant's photosynthetic chemical storage. Estimates of the total amount of sun energy we're able to capture directly range from 50 to 1500 terawatts, depending on how much land you're willing to use. He reckons there's onshore potential for 60 terawatts (equivalent to 60,000 nuclear power plants.) He tells us it would take 0.16% of the Earth's surface to produce 20 terawatts at current efficiency. That's 40 watts per square metre.

According to BERR (nee DTI), In 2007, the UK used 226 million tonnes of oil equivalent (or 226 mega-toes!) That comes out at 0.3 terawatts of total consumption. (That sounds about plausible: the US, according to Lewis, is running on about 3 terawatts.) To get all our energy from solar would require 7500 square km - presuming we could get the average wattage, which is probably wrong. I've included a pic of how much UK land this would take up (avoiding the usual government tactic of e.g. flooding the Welsh or building nuclear power stations as far as humanly possible from London.)

This is entirely a ballpark figure - converting the whole UK economy to electric power would take infrastructure alterations beyond count. Nathan Lewis rather gleefully says that, for his own square of solar in the US, he's never actually met anyone who lived there. The square, though, is of course only an illustration of solar acreage that would in reality be distributed all around the country. But it's a good enough indicator of the scale of the job.

Lewis' best number for getting a handle on what needs to happen is this: if nuclear were to be our escape route, we'd need to be building one power station every other day. That's only to meet the 10TW target by 2050, so accepting 550ppm. Plenty of people think that going over 450ppm is a Very Bad Idea. So - what are we going to do?

St. Matthew's Island

It's odd. This is what we appear to be doing: carrying on working in the office while the carpet is on fire, and it's spreading this way. I mean - if something's on fire, you put out the fire. So we should, clearly, kill the power to everything unnecessary until such a time as the alternatives develop. This could be done by taxing the bejesus out of fossil fuels. But it won't happen. A trillion dollars to save global banking structures? Fine, I've got it in my back pocket. That's restoring the natural order of nature after all. But the Earth? It's OK - someone probably has a spare one in the basement.

I'm reminded of Agent Smith:

I’d like to share a revelation that I’ve had, during my time here. It came to me when I tried to classify your species and I realized that you aren’t actually mammals. Every mammal on this planet instinctively develops a natural equilibrium with its surrounding environment, but you humans do not. You move to an area and you multiply, and multiply until every natural resource is consumed. The only way you can survive is to spread to another area. There is another organism on this planet that follows the same pattern. Do you know what it is? A virus. Human beings are a disease, a cancer of this planet. You are a plague, and we... are the cure.

A virus, ironically enough, is a machine: a nano-device capable of injecting a small strand of RNA or DNA in through a cell wall. This small strand hacks the cell's replication system to reproduce itself - copies continue to be made until the cell itself bursts, releasing anything from 100 to 1000 new nano-machines. This site notes - 'viruses possess a capacity to increase in number at a rate that is well in excess of the rate at which their cellular hosts can increase in number.'

The point at which the cell bursts is called viral yield. To warp the analogy somewhat, one can imagine some future-form of human bursting from the planet and spreading exponentially throughout the galaxy. We'd have to have become capable of stasis for crossing light-year distances, but hey - why not? The universe can wait.

It's not true, of course: any species introduced to an environment where it can stuff itself silly will also breed itself silly. A recent example comes from St.Matthew Island, where reindeer did just that. Starting in 1944, it ended in one winter nearly killing them all off when the food ran out.

As a species, we're able to leverage our brains to push these limits - as with Green Revolution technology. But here's Jeremy Leggett talking at the recent Soil Association conference on 'transition'. The oil and gas industry -

- has been and is susceptible to the same kind of systemic cultural failing that we now know the financial sector has. That takes the form of a kind of irrational exuberance about how much oil is out there, and how quickly they can deliver it. If that analysis is correct, nobody is particularly lying, there's no conspiracy. It's just a human failing that has institutionalised itself in this industry, and that will leap up and slap us in the face, in the same way as we've been shocked by the emergence of the credit crunch.

It's not just oil and gas, it's all of us. Yesterday was much like today; surely tomorrow will be too. And why not think that way? Even insane tyrants tend to have an instinctive conservatism and limit themselves to a thousand years. As a species, if we've ever tried to structure things beyond a very short term it's rarely worked out well. Generally without fail, history has been inflicted upon us in the interim. Doubtless there's plenty more history to come. But Nathan Lewis had a lovely quote in his talk:

It's hard to make predictions, especially about the future.

What are we going to do?

OK, so I didn't quite answer the question. What are we going to do? Excuse me if I don't attempt a fullsome answer at this stage: I'm going to have a go at covering some facets of the question in upcoming entries. One of the themes I'll return to repeatedly - since it ties to my PhD - is the tension between what will happen 'on the ground', in places where people live, work, eat and (currently) drive, and what will happen globally. Nathan Lewis ends his talk thus:

There are four securities that are important: energy security, national security, environmental security, economic security. We can all prioritise these in different orders depending on our personal view, but they're all there and all important. We'd like to get all four at once. If we do build those nuclear power plants it's not clear we'll get all four - maybe only two out of the four. If we go to coal and sequestration does not work, we might get energy security and economic security. We might have to fight for our resources, so we might not get national security. Wars have been fought over energy in the past, and there's no reason to think they won't be fought again. If you were to go to solar and renewables you would satisfy all four of those. It's the only option in our portfolio that could - and so I think we oughta do that.

However we deal with these four, we shouldn't misunderestimate national security, in the broadest sense. We've already seen, during the food price hikes last year, both governments and those who could afford it began hoarding: buying up so much that others had none. Hoarding is already happening in some pretty unlikely ways. It's one of the most important questions - and one of the very few I haven't tried to cram into the PhD: trade links still mean peace. Where the drive for localism starts meshing with this instinct to draw into ourselves (note the BNP's interest in the ">transition towns movement) bad seeds are being planted.

Given how unlikely we are to succeed in maintaining current power levels, minimising the political impact of energy descent is going to be as big a job as getting to a carbon-free future.

On that cheery note, I'll say tata.


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