As the latest climate change conference in Bonn draws to a close today, the full implications of commitments made at COP17 are beginning to sink in. The nations of the world find themselves united by a challenge that is both eye-watering and conceptually simple: hold the global average temperature increase below 2°C versus the long-term pre-industrial average, by taking actions that are consistent with our best understanding of science, while still meeting society’s development needs. The challenge is monumental because history has no precedent for the scale and rate of the transformation that is required in terms of how we organise ourselves and deliver essential goods and services. It is straightforward because the science tells us we can only hope to achieve this objective by engineering a zero carbon energy system by mid-century.
What does a zero carbon energy system look like? On the supply side, it’s very easy to visualise: if we insist on setting fire to coal, oil and natural gas to deliver our energy needs, we must capture and sequester the emissions. This is unlikely to be achieved unless we ensure that all combustion occurs in stationary plants. In any case, the total share of fossil fuels in the energy mix will diminish in favour of sustainable renewable energy that arrives free of charge from the sun, either directly via photovoltaic (PV) cells and concentrated solar power (CSP) plants, or indirectly via wind turbines and hydroelectric dams. On the demand side, save for a few niche applications around the margins, the global energy system will electrify. This is both necessary and inevitable – the only remaining question is how to expedite the zero carbon energy technologies by bringing down their cost. We can start by removing enormous subsidies enjoyed by fossil fuels.
Where does this leave the transport system? It is the blood supply of our economic system, which is wholly based on the movement of people and things. Today, 93% of the primary energy consumed in transport is supplied by crude oil, increasingly disadvantaged due to its uneven geographical distribution – proven oil reserves are concentrated in the hands of a few relatively unstable countries – and geological fundamentals that force us to expend more and more energy to extract each successive barrel. Setting aside the climate change imperative, we still have a raft of convincing reasons for kicking our oil habit, not least the extraordinary extent to which our economic wellbeing has become hostage to political events in faraway lands over which we exercise little control.
Again, the solution is conceptually very easy: the transport system – at least, the surface transport modes – must electrify like everything else. The good news is that electric drive technology is spectacularly energy efficient: with existing technology, the combination of batteries and electric motors is twice as efficient as the theoretical maximum that internal combustion engines can ever achieve, or four times more efficient than today’s conventional vehicles. This means that even if electric vehicles are running on coal-fired electricity, their life-cycle carbon emissions are no worse than the very best of their mechanical counterparts. And of course, as the electricity supply decarbonises – as it must – electric vehicles get cleaner over time. The reverse is true of conventional vehicles as the liquid fuel supply gets successively more carbon-intensive.
Eliminating tailpipes means eliminating tailpipe emissions, not only CO2. The health burden of SO2, NOx and particulate matter – especially in crowded urban landscapes – represents a considerable drain on the fiscus. Electric vehicles connected to the grid when not in use also provide a distributed storage system that can help to balance the variable nature of renewable energy technologies. The entire energy system becomes more efficient as a result. Furthermore, every country on Earth is capable of generating electricity with domestic resources. The same cannot be said for gasoline and diesel, the costs of which are both high and volatile. As for biofuels, if we can manufacture them sustainably without compromising food and water supplies they will be required for aviation, which cannot do without the energy density that only comes in liquid form.
Electrification of transport is not limited to cars, which are still beyond the financial reach of many. China, for instance, has some 120-million electric bicycles on the road today, more than double the country’s automobile population. Electric buses – powered by batteries or overhead lines – ply the streets of many Chinese cities, and some 45 000 km of high-speed (electric) rail will be in place by 2015. The trends are clear: whereas the United States and Europe embarked upon their automotive revolution while oil was cheap and abundant – and the societal costs of burning it were unknown – China faces a totally different reality of expensive oil and an acute sense of vulnerability to climate change and urban air pollution. No wonder the Chinese government has identified transport electrification as a central pillar of the nation’s development.
As for South Africa, in many ways the national context is much closer to China than the US and Europe: a carbon-intensive energy system in urgent need of radical overhaul, a legacy of disastrous 20th century social policy, pressing inequality challenges, an enviable endowment of renewable energy resources (as yet untapped), no domestic competitive advantage in oil-based transport systems, and, perhaps most importantly, an optimistic forward-looking population. With per capita vehicle ownership only a fraction of that in so-called advanced economies, it is not too late for South Africa to select a different course and base its future mobility systems – and therefore its entire economy – on renewable electricity.