There is no magic bullet, no single thing that can replace all our fossil fuel combustion at a stroke. We can’t swap our fossil fuel consumption for something less harmful completely, immediately.
It would be good if we could do it really quickly, but we can’t. If we simply stopped using fossil fuels at a stroke, one of the results would be deaths on a massive scale, from cold, thirst, hunger – and violence. This could be as bad as what we’re trying to prevent! We could stop some of our more frivolous uses of fossil fuels pretty quickly without replacing them, but mostly we have to develop replacements and gradually reduce fossil fuel use as we do so. To some extent this is being done, but too gradually – we need a greater sense of urgency, we need to attach more importance to the process – and we need to remember that the replacements are supposed to be replacements, they’re not supposed to be additions, with the fossil fuels still being used as profligately as before.
That’s the immediately bit. Now let’s consider the completely bit. Actually, we don’t need to replace fossil fuel use completely. We can be pretty sure that the Earth’s systems can cope with some human carbon dioxide production – in fact, it’s possible that human carbon dioxide production is the reason the last few thousand years’ climate has been relatively stable (see Climate: Patterns in the Chaos), and that continuing fossil fuel combustion (on a much reduced scale) is the only way we can continue to stave off the otherwise inevitable arrival of the next ice age.
It would, anyway, be very difficult to replace fossil fuel use completely – at least, in the foreseeable future. Let’s concentrate on how we can reduce it – drastically, but not completely.
(I’ve been writing “fossil fuel use” – but actually not all fossil fuel uses produce carbon dioxide. Fossil fuels can be used as feedstocks for some chemical processes, such as plastics manufacture, where the carbon ends up in the products, not as carbon dioxide vented to atmosphere. There may be other issues around such activities, but in the main they’re not a global warming issue, and certainly not a big one. I’ll continue to write “fossil fuel use” meaning those uses that produce carbon dioxide.)
Let’s consider that list of fossil fuel uses: generating electricity, keeping ourselves warm in our homes and workplaces, heating water, transport, cooking and industrial process heat. I’ll deal with them one at a time – and remember, we’re trying to reduce fossil fuel use a lot, but not necessarily immediately, and not necessarily completely. If we can make a 20% cut somewhere relatively easily but only improve on that with difficulty, then it might well be better to do that and then look somewhere else for another cut, and only come back to the difficult case when we’ve done all the relatively easy things. But we shouldn’t spend too much time doing a hundred easy cuts of 0.001% each, and forget to do the big cuts altogether!
The hundred easy cuts of 0.001% each are things like turning off equipment that’s on standby (actually 0.3%, according to one government source – but I strongly suspect that this is an overestimate).
The frivolous uses I mentioned earlier are a much bigger deal. We could cut out a great deal of fossil fuel use in transport and in industry simply by stopping some unnecessary activities altogether. Many of the products of industry are simply junk, bought by consumers just because they’ve got the money to buy them, and they’re there to be bought, but not contributing in any significant way to their lives. How do we stop people doing this? I don’t know – although economic recession seems to be quite an effective way! There are issues here about employment – but employing people to produce and transport junk is make-work, it’s not really productive (yet its output appears in GDP figures! Damned lies and economics) If there aren’t enough worthwhile things to do to occupy the whole workforce forty hours a week, let’s cut down the working week – don’t make work. Of course there are worthwhile things to do anyway – we’ve all that infrastructure to build to replace fossil fuel use. There’s a skills issue there, of course, and a training issue behind that.
This is about 30% of our fossil fuel use. It’s one area where it’s actually relatively easy to see how to make a big reduction – by using renewable sources of energy. (Nuclear power is NOT a good answer, or even part of one – but that’s the subject of another essay Nuclear Power?) At the moment, at the present state of research and development, wind turbines are the biggest and best source of renewable energy for electricity generation, and we should be building them much faster than we are, and aiming for a much higher percentage of our electricity production with them. There’s an intermittency issue with wind, but when the wind blows reasonably strongly we could generate all our electricity (or almost all of it) from the wind, and turn off (or turn right down) the fossil fuel burning power stations. When the wind isn’t blowing much, we’d still have to use fossil fuels, but we could be making a big reduction in carbon footprint here. When it’s blowing a lot, we’d have electricity to spare – which could be sold cheaply for uses which are currently too power-hungry to consider, or stored for future use. Storage of energy isn’t without costs, but it’s not as difficult or expensive as the opponents of wind and solar electricity generation like to pretend (see Storing Energy). Research and development in this area would be far cheaper and far more worthwhile than in nuclear generation, particularly fusion!
Keeping ourselves warm
This is about 26% of our fossil fuel use. Of course part of this overlaps with the electricity generation use, because some of the electricity is used for this.
There are several things we can do here, which between them could make quite a big difference quite quickly. In the longer term, if we can generate plenty of electricity from renewable sources, then a changeover to electric heating would reduce our carbon footprint. There are ways to use electricity for heating more efficiently than is usually done, too – but that’s another essay.
The most immediate thing we can do about heating’s carbon footprint is to turn the thermostats down! We used to survive with our houses much less warm than we keep them nowadays. I’m not suggesting we should go back to shivering every time we climb out of bed, but just turning the thermostat down two or three degrees would make a big difference to our energy consumption – and we can easily wear slightly warmer clothes.
Improving the insulation of our homes and other buildings is also relatively easy. It’s being done, but could be done more rapidly. In some properties, reducing draughts would reduce heat loss – but you have to be careful not to reduce ventilation too much. There are ways of having ventilation without the normal associated heat loss.
Fossil fuel power stations only convert less than half the energy in the fuel into electrical energy – the rest is lost as heat. In some places, this waste heat is used for heating buildings, a process called CHP (Combined Heating and Power). CHP is being adopted more widely, but that could be done a lot more rapidly. It can also be done locally, by replacing gas boilers in homes and other buildings with micro-CHP units. This makes CHP, with its very substantial carbon footprint reduction, feasible in many places where it would not be otherwise.
Finally, we could partially replace fuel burning for heating with renewable energy sources, such as solar. This is being done to some extent, but much less than it could be, and much more slowly than it could be. Solar heating has the advantage that it’s fairly easy to do – and the disadvantage that it’s least available when it’s most wanted. Wind is much better from this point of view – it’s more often available in cold than in warm seasons, and a windy day takes heat out of a building much faster than a still day, even at the same temperature. But wind is not as easy to convert to heat – the easiest way is via electricity.
This is about 9% of our fossil fuel use. Again, part of this is an overlap with electricity generation use. CHP and renewable energy sources are the ways forward here.
This is the other biggy – 34% of our fossil fuel use. It’s also the most difficult area to change to renewable energy. The biggest improvements would be:
1) Changing to smaller cars with less “performance”, using cars less by switching to buses or trains, making fewer and shorter journeys, and walking or cycling locally as much as possible. There would also be gains in health from walking or cycling more (particularly if proper provision were made for cyclists).
2) Reducing consumerism. This would reduce the demand for goods vehicle movements.
3) Reducing the expectation of speed in travel. Trains, buses and cars use much less fuel if they go more slowly. Accidents, particularly for cars and buses, are also fewer and less serious.
4) Reversing the trend to increased air travel, which is particularly profligate. Using trains or ships instead.
(3) and (4) would both be helped by reduced working hours and increased leisure. Why do we have such short holidays and such long working weeks, while there are still so many people unemployed? And why do we spend so much time producing – or importing, distributing and selling – stuff that we really don’t need at all?
Switching to renewable energy is much more difficult for transport, other than rail where electricity from a renewable source can be used. Electric cars could eventually be part of the solution, once electricity is largely from renewable sources, but they’re actually of very limited relevance. Hydrogen is also of very limited importance (see Hydrogen. Yes, but...). Liquid biofuels could be of some significance, but it’s important to avoid conflict with food production, or destruction of rainforest (Biofuels. Yes, but...).