In a sense, the way we generate and use energy is the cause of the problem. By digging up/drilling out the billions of tons of coal and oil that powered the Industrial Revolution and largely continue to power our world today, we’re releasing stored energy from safe underground storage and putting it into the atmosphere in the form of greenhouse gases and other pollutants. How we source, generate and use energy in the future will determine whether we, our children and the vast array of other living things on this unique planet of ours will thrive, survive or go extinct.
At the root of almost all the energy we use is the sun. (I’m leaving nuclear energy out of this – although the heavy trans-urananic elements have their origins in the death-throes of ancient stars, they’re not derived from our own sun). The energy locked in oil, coal and natural gas is derived from the sunlight that fell on ancient plants and was photosynthesised into carbon compounds that then fossilised into the hydrocarbons we depend on now. In a very real sense, when we put a lump of coal on the fire, we’re returning ancient solar energy into the atmosphere. All the fossil fuels share this common origin – they represent stored energy from millions of years ago.
I find it helpful to think of energy sources by analogy with bank accounts. We’re all familiar with the idea of having a current account, where money comes in regularly (daily solar output from the sun) and goes out regularly (waves, winds powered by the sun, solar input falling on the Earth’s surface). If you spend more than you get paid, you develop an overdraft – which is a bad thing. Of course in terms of energy, we can’t use more energy from renewable sources than is there to begin with – there’s no overdraft facility on the account. Fossil fuels represent a savings account, perhaps a trust fund established by our distant ancestors, all those millions of years ago. When we run short on the current account, we can dip into that savings account and spend the ‘capital’ that’s been sitting there.
Think of the Industrial Revolution as a spendthrift finding the keys to the strongroom and starting to spend the accumulated hoard of energy and you start to get the idea of what we’ve been doing with energy for the past couple of centuries. We’re spending our energy wealth far faster than it comes in! Of course eventually we’ll get to the bottom of the strongroom and there won’t be anything left, but that’s another can of worms entirely and maybe I’ll get to the Peak Oil/Peak Gas/Peak Coal discussion in another post sometime. For now, let’s just leave it out of the discussion – there’s enough in the strongroom savings account for us to carry on throwing energy around for quite a while yet, though some of the sacks of gold are getting a bit harder to dip into.
The immediate problem is, we’ve put all that stored energy back into the system and the Earth is having to absorb it into the various energy systems that move air and water around the planet’s surface. The oceans are getting warmer – the latest IPCC report calculates that the rate of that warming is in the region of 0.11 degrees celsius per decade since the 1970s in surface waters. That doesn’t sound like a lot, but when you remember the size of the oceans and the fact that ‘surface’ water is a layer of water 700m thick, that’s a heck of a lot of energy! (There’s a calculation on that, too – 170,000,000,000,000,000,000,000 joules. Compare that to how much energy it takes to run your body for one day – about 7,500,000 J.) Similarly, the air is getting warmer, too – about 0.7 degrees celsius in the last century. Again, that’s a lot of air to warm up, even if it doesn’t sound like a lot of warming!
Can we carry on spending the ancestral energy capital at this rate? Not indefinitely, because it’s a finite store of energy (and we’re getting back to the peak energy theory again…) but more importantly, not without changing the amount of energy, in the form of heat, that circulates on the Earth’s surface. Even though we’ve used some of that liberated energy to power machinery, dig mines, build skyscrapers and all the rest of it, we’ve put waste heat into the atmosphere and the oceans directly, and the waste products from liberating that energy are greenhouse gases that trap incoming solar energy from the sun as heat, rather than it bouncing back into space and being lost from the system.
There are a number of things we can do to try and avoid further greenhouse gases accumulating in the atmosphere. We can clean up our emissions – filter soot from exhaust gases, develop carbon capture and storage techniques, burn cleaner fuels. We can try to remove existing pollutants from the air that’s circulating around us – various schemes have been proposed to filter air through huge carbon capture devices, so the carbon dioxide reacts with chemicals in the devices and can be stored as a harmless solid material. We can also reduce our energy use – and this is the one people don’t like to get to grips with, because it restricts our personal actions.
Don’t hop in the car to do the shopping or drop the kids at school. Don’t fly to a sunny tropical beach for a couple of weeks’ holiday. Don’t buy the latest electronic games and gadgets, don’t run a computer (yes, I know, I am aware of the irony of typing this on a computer on the internet)….
It goes much further than that, too. If we are to stabilise global climate change below 2 degrees celsius of warming by 2050, we need to cut our emissions to 80% below the level we (as a planet) emitted in 1990, and we need to do that before 2020.
It’s very difficult to imagine doing that. When I think that the Chinese are busy building a coal-fired power-station every week, I dispair of achieving it. It will take a massive, personal committment by every human on the planet and a lot of personal sacrifices (particularly in the developed, industrialised world) to achieve such a huge reduction in emissions. It’s too easy to say, but it can’t be done because of (Chinese power stations, American gas-guzzling cars and trucks, etc) so nothing I personally do can have any effect…. so I won’t bother.
It’s also very hard to expect people struggling out of poverty in the developing world to accept that we, in the comfortable, luxurious setting of our food-rich, gadget-rich car-rich personal lives, are telling them that they shouldn’t aspire to what we have – three square meals, central heating, personal transport, nice clothes, etc. What right does any pampered European citizen have to tell a barely-subsisting African citizen that they shouldn’t have what we take for granted, because it’s bad for the planet?
The truth is, the developed world will have to take a very substantial cut in our standard of living in the next few decades, and if we don’t do it voluntarily, adaptively, our children and grandchildren will be forced to it in desperation towards the end of this century. We’re standing on the edge of a cliff at the moment – the question is, do we, now, find parachutes and jump – or do we refuse and leave our descendents to fall off without any parachutes at all? We have to make this transition, but it’s our choice whether we start changing now, choosing how we do it, or whether we ignore the problem and are forced to accept whatever comes along in the future. It’s really no more complicated than that. We can see the flood coming – we can choose now as the time to design and build the ark, or we can choose to look away and we’ll be paddling for our lives when the water flood arrives!
A further nasty kick in the tail with the energy problem is that we also use hydrocarbons and a lot of energy to make fertilisers and pesticides for our intensive farming systems. In order to cut emissions, we should be looking to reduce our use of such things…. but in order to double world food production, which is the minimum required to feed the anticipated 9.6 billion people who’ll be alive on this planet by 2050, we’re going to need every trick in the box…..
I’ve discussed adapatation and mitigation strategies for energy use here.