1.1 tons CO2e
> That’s nearly six weeks of a 10-ton lifestyle—equivalent to a couple of return flights from San Francisco to Vancouver.
The carbon cost of health care in the U.K. is around 170 g per pound sterling (110 g per US$1) spent. Although the U.S. and Canada have very different health care systems, the carbon intensities are probably reasonably similar. If so, looking after your health turns out to be a fairly low-carbon way of spending money. And in terms of the quality of life improvements we stand to gain from it, health care when we need it must be one of best ways of spending our carbon budget.
That said, a big operation clocks up a big footprint. The typical cost of a heart bypass to the U.K.’s National Health Service is £6,324 ($9,500).1 If we assume that this operation is averagely carbon intensive U.K. health care spending, that adds up to more than 1 ton CO2e.
Overall, U.K. health care has a footprint of 27 million tons CO2e, or just over 3 percent of the national consumption footprint. Electricity and fuel used by health services account for less than one-third. Drugs account for nearly one-fifth. My catch-all “other” category is nearly one-third of the total, reflecting the variety of equipment and other stuff that is required to keep us healthy. Paper and cardboard surprised me at a massive 2 percent of the footprint of all health care. I’d like to think this is not the stuff that clogs up the filing cabinets of one of the world’s biggest bureaucracies but rather the consumables used to keep things clean. So what can we do to reduce the emissions of our health care? The best option is to stay healthy, of course. This might involve cycling (safely) or walking more, and thinking about the amount of meat and dairy in your diet—all things that will reduce your direct footprint, too, and are discussed elsewhere in this book. When you do actually need health care, be careful with medical resources, but relax in the knowledge that at around 110 g CO2e per US$1, it is one of the lower-carbon ways for you or your government to spend money.
3.5 tons CO2e producing a solar roof capable of generating
1,800 units (kilowatt-hours) of electricity per year
50 tons CO2e lifetime savings—that’s 5 years’ worth of 10-ton living
> WARNING:This section contains myth-busting payback calculations that will interest some more than others.
I’m going to do the financial sums and the carbon sums and then put these both together to see how electricity-producing photovoltaic solar panels rate as a cost-effective way of saving carbon.
First, the financial bit. Some governments offer a “feed-in tariff” to reward individuals who install solar panels on their roofs. In the U.K., for example, homeowners are offered a massive 36.5p (57 cents) per unit generated.2 This handout is guaranteed for the next 20 years. On top of the feed-in tariff you can still use what you generate yourself (thus cutting the amount you have to buy) or sell it back to the grid to get even more revenue. It’s an incredibly generous government handout (especially given the U.K.’s financial situation), and if currently available micro-photovoltaic panels are a viable source of electricity, surely we should all be diving in?
U.K. analyst and author Chris Goodall3 has done sums on the financial payback from micro-renewables. He estimates that in the U.K. it will cost you £10,000 ($15,000) to get a set of panels installed that is capable of providing you with 18,000 kilowatt-hours per year. Once you have taken account of income from the tariff, your sales to the grid and reductions in your grid electricity bill as well as annual maintenance costs, Chris thinks you can make a return of £730 ($1,125) per year. This figure suggests a financial breakeven after 14 years. That sounds fine, but what this is really saying is that provided everything goes to plan, you will be exactly as well off as you would have been if you had kept the money in a box under your mattress. Such a simple “payback period” calculation would be fatally flawed because it would ignore both the fact that you could have done something else with the money, where at the very least you would have gotten a bit of interest to offset inflation, and the fact that even the surest-looking projects, backed up by manufacturers’ guarantees, carry a degree of risk.
More realistic payback sums need to have a way of taking into account the fact that money in your hand right now is worth more to you than the promise of the same amount of money to be paid to you in the future provided that things go well. This can be done by applying a so-called discount rate to the future payback. Applying a 10 percent discount rate (a fairly sensible figure) is equivalent to saying that you’d be just as happy to have $900 in your pocket now as you would be to have $1,000 promised to you in a year’s time on the condition that your photovoltaic panel project is still going according to plan. If we following the same logic, a promise of $1,000 in two years’ time is worth just $810 to you today, and the financial return that you hope to get in your 14th year is worth less than one-fifth of the same money in your hand right now. So, what happens to your solar payback period once a 10 percent discount rate has been applied? It turns out that you would never get more than two-thirds of your money back, even if your panels lasted forever. (Which they won’t. After 20 years they can be expected to be functioning at less than 80 percent efficiency, and after 40 years they will probably have had it.) In other words, don’t buy a solar roof purely as a profit-making venture, even with the government’s wildly generous feed-in tariff.
If your government or state only pays you, at most, the market rate for the electricity you feed into the grid (as is the case throughout North America as I write), the finances are likely to be disastrous.
But what about the carbon sums? I’ll guesstimate that the £10,000 ($15,000) you spend is half on the kit and half on the installation. To give the carbon sums their very best possible chance, I’ll generously overlook the footprint of installation and use the lowest plausible figure I can take from my input–output model for the manufacture of the panels: 0.47 kg CO2e per dollar spent. That gives the panels a footprint of 3.5 tons. If we assume that the electricity generated all replaces output from coal-fired power stations rather than the grid average, then the carbon savings per year is about 1.8 tons, and you’d pay back the carbon in about 2 years. So where does that leave us? After 40 years your net cost (your initial investment minus the paybacks each year with discount rate applied) is still over £3,000 ($4,600). The government will have invested £13,000 ($20,000) over the 20 years of the feed-in tariff and (I’m assuming) nothing from then on. Something like 50 tons CO2e will have been saved.4 That’s a cost of £330 ($500) per ton, even worse than a micro wind turbine and dramatically worse than offshore wind.
Are there any reasons to get a solar photovoltaic roof? Perhaps. You might want to invest in a developing technology. Or you might simply want one for fun. If you need to buy things to prove your status in society, solar panels are one of your most carbon-friendly options. We spend billions on mindless junk and flights around the world for that very reason: status. With the panels you can show everyone that you have spare cash but that you also think about the world. Photovoltaic panels can replace the SUV, and you might still be in the vanguard of this trend if you are very quick.
Flying from Los Angeles to Barcelona return
3.4 tons CO2e economy class
4.6 tons CO2e average
13.5 tons CO2e first class5
> Three economy trips are a whole year’s worth of 10-ton living. One trip is equivalent to 340,000 disposable plastic carrier bags.
In other words, for your plastic bags to have the same footprint as just one trip from L.A. to Spain, you would have to go to the supermarket every single day for 10 years and return each time with 93 disposable bags. A flight from New York to London has roughly half the impact. The distance is a bit more than half, but there is a slight efficiency gain because there is less fuel to carry. New York to Vancouver or San Francisco is just over a third of the distance.
A Boeing 747 carrying 416 passengers burns through 116 tons of fuel on the 9,700 km (6,030-mile) flight each way. Almost one-third of the total weight on take-off is fuel. As the fuel burns, it creates three times its weight in CO2. But the impact is worse still because high-altitude emissions are known to have a considerably greater impact than their low-altitude equivalents. The science of this is hideously complex and poorly understood,6 but there is still a clear case for applying a multiplier to aviation emissions to take account of their extra impact. I have used a factor of 1.9.7 Aviation is sometimes said to account for between 1 and 2 percent of global emissions. These statistics ignore the effect of altitude. The proportion is also higher in the developed world, especially in those bits of it, like the U.K., that are surrounded by sea. British travelers’ personal flights account for a huge 8 percent of the carbon footprint of all consumption. That rises to nearly 12 percent once business flights and air-freight are added on.
In terms of your own lifestyle it might be much less than this. Many people never fly at all. Then again, for some people, flying accounts for the overwhelming majority of their total footprint, and trying to cut carbon in other areas might simply be a misdirection of attention, distracting them from what matters. First-class and business-class tickets are particularly high in impact simply because your seat uses up more of the plane and because by paying more money you provide a greater proportion of the commercial incentive for the flight. It’s hard to imagine a low-carbon flying technology coming to the rescue. The physics of flight simply does not allow us to reduce the energy it takes to keep us in the air by more than a few percent,8 and for the foreseeable future that energy has to come from fossil fuels. Nevertheless, there are still some efficiencies to be had. One of these is the automation of air-traffic control to replace the current archaic manual system. Humans are woefully unable to calculate optimum flight paths in real time with hundreds of planes in the air at once, all competing for space and time slots. One estimate is that upwards of 9 percent efficiency improvements are possible.9
Ultimately, then, it’s hard to avoid the conclusion that most of us need to fly less. But that needn’t make our lives any worse. Make your flights count: go for longer but less often, and do things you really couldn’t do at home. For the rest, try local trips, which involve less travel time and therefore more holiday. After all, the experiences of getting to an airport, hanging around in a departure lounge, and then sitting cooped up for hours are intrinsically terrible ways of spending time. Also think about where you fly to: the closer the destination, the fewer the emissions. One myth is that long-haul flights are automatically more efficient per mile than short-haul because they involve proportionally less time taxiing, lining up, taking off, and landing. This isn’t necessarily true, because the long-haul flight has to lift more fuel. The truth is that the most carbon-efficient way of getting across the world is in several hops—but not too many.10 But none of this changes the fact that the further you fly, the larger the footprint.
Of course, the flying conundrum affects companies as well as individuals. I work with a few businesses for whom flying is a key issue. They know it’s high in carbon, costly, and time consuming. They also know they have always had strong business reasons for doing it. New thinking is required to break out of old habits. Video conferencing may never fully replace human contact, but it is a lot cheaper and easier once you are fully conversant with the technology. What is worth more, one face-to-face visit or ten video link-ups?
It is difficult to see a place in the low-carbon world for much air-freighted food (see Asparagus), let alone durable goods such as clothing. Some garments are air-freighted simply to reduce lead times and cut the cost of stock that is tied up in transit at sea. Air-freight labels are one piece of consumer information that would surely be simple and helpful. Currently these are found on some supermarket fresh produce but nowhere else.
I’m sometimes asked about air freight from developing countries: “Surely it’s good to keep supporting that country by carrying on the trade!” In broad terms, I don’t think so. The argument is a bit like saying that you should keep the arms trade booming so that people can keep their jobs. Economies need to be powered by people doing things that are useful. Anything else is an unsustainable nonsense.
2.7 tons CO2e nitrogen fertilizer efficiently made and sparingly spread
12.3 tons CO2e the same stuff made inefficiently and used in excess
> A real carbon opportunity: up to half a percent reduction in global emissions—it’s dead easy and has no bad side effects.
Nitrogen fertilizer is a significant contributor to the world’s carbon footprint. Its production is energy intensive because the chemical process involved requires both heat and pressure. Depending on the efficiency of the factory, making 1 ton of fertilizer creates between 1 and 4 tons CO2e. When the fertilizer is actually applied, between 1 and 5 percent of the nitrogen it contains is released as nitrous oxide, which is around 300 times more potent than CO2. This adds between 1.7 and 8.3 tons CO2e to the total footprint,11 depending on a variety of factors.12 Here’s how the science of it goes. All plants contain nitrogen, so if you’re growing a crop, it has to be replaced into the soil somehow or it will eventually run out. Nitrogen fertilizer is one way of doing this. Manure is another. Up to a point there can be big benefits. For some crops in some situations, the amount of produce can even be proportional to the amount of nitrogen that is used. However, there is a cut-off point after which applying more does nothing at all to the yield, or even decreases it. Timing matters, too. It is inefficient to apply fertilizer before a seed has had a chance to develop into a rapidly growing plant. Currently these messages are frequently not understood by small farmers in rural China, especially, where fertilizer is as cheap as chips and the farmers believe that the more they put on the bigger and better the crop will be. Many have a visceral understanding of the needs for high yields, having experienced hunger in their own lifetime, so it is easy to understand the instinct to spread a bit more fertilizer. After all, China has 22 percent of the world’s population to feed from 9 percent of the world’s arable land. There are other countries in which the same issues apply, although typically the developed world is more careful. Meanwhile in parts of Africa there is a scarcity of nitrogen in the soil and there would be real benefits in applying a bit more fertilizer to increase the yield and get people properly fed. One-third of all nitrogen fertilizer is applied to fields in China—about 26 million tons per year. The Chinese government believes there is scope for a 30 to 60 percent reduction without any decrease in yields. In other words, emissions savings on the order of 100 million tons are possible just by cutting out stuff that does nothing whatsoever to help the yield. There are other benefits, too. It’s much better for the environment generally, and it’s cheaper and easier for the farmers. It boils down to an education exercise... and perhaps dealing with the interests of a fertilizer industry.
0.1 ton CO2e per year average Malawian
3.3 tons CO2e per year average Chinese person
7 tons CO2e per year world average
15 tons CO2e per year average U.K. inhabitant
28 tons CO2e per year average North American
30 tons CO2e per year average Australian
Figure 8.1 shows two ways of looking at the emissions per person for various countries: the official “direct” footprint and my estimate for the “consumption” footprint. The direct footprints include all the greenhouse gases released inside a country’s borders; the consumption footprint is adjusted to take account of imports and exports, giving a total that represents all the goods and services ultimately consumed by a typical person in each country.
For the U.K., the direct average footprint of 11 tons per head goes up to about 15 tons once you include imports and international travel and shipping. I have estimated that for other developed countries the same markup of about 4 tons per head seems reasonable, in which case for North America, 24 tons per head becomes 28 tons. In China the effect works in reverse. About one-third of their emissions go into exported goods, so the footprint of Chinese consumption is only about two-thirds of the emissions that physically come out of the country itself. I’ve estimated that a similar story applies to India but to a slightly smaller extent.
FIGURE 8.1: Emissions per person and an estimate of footprint per person.
My estimates of the difference between a nation’s emissions and its consumption footprint are very conservative, for one very important reason. The figures are based on the flawed assumption that the overseas production is exactly as carbon intensive as the U.K. equivalent. In other words, it assumes that if you have your washing machine, your computer and your pair of jeans made in China they will have the same embodied footprint as if they were manufactured in the U.K. We know that this is not true and there is a strong argument for using much higher figures for most imports, based on inefficient production and more polluting electricity generation in coal-dependent exporting countries such as China.