Dave Elliott: The European Commission has signalled that it is considering a “net zero” emissions goal and, in the UK, the Labour Party now has that as a key policy – net zero by 2050 rather than the current 80% emissions cut target by 2050. What does net zero mean, and is it possible? The first part is easy. Net zero means that carbon dioxide and other greenhouse gas emissions are reduced 100%, to zero, although some can be allowed if compensatory carbon negative processes are introduced, for example, air capture of carbon dioxide. How to achieve this is a bit more complex. The most obvious approach is not to produce any more carbon dioxide. In the energy sector that means using non-fossil energy sources, i.e. nuclear or renewables. However, neither is entirely carbon-free – at present we use fossil fuel to make the materials for the energy conversion technologies involved and, in the case of nuclear, to extract and process nuclear fuel. Nevertheless, they are both low-carbon options. In its new Green Transformation pamphlet, the Labour Party says it will use both nuclear and renewables to “ensure that 60% of the UK’s energy comes from low-carbon or renewable sources within 12 years of coming to power”, i.e. by 2030 if that event happens soon. The inclusion of some new nuclear is controversial but together, renewables and nuclear would supply 85% of UK electricity, up from 50% now (30% renewables, 20% nuclear). However, renewables would no doubt continue to dominate the mix and presumably then be ramped up further to get to near 100% of supply by 2050. Some idea comes from a new study by the European Climate Foundation (ECF) of EU pathways to zero emissions. It says that “commercially available solutions can already take us about 75% of the way to net-zero if deployed at scale. The remaining 25% can be achieved based on known approaches and technologies for which further scaling up and commercialization is needed”. Labour’s approach so far, at least as outlined in the new pamphlet, is a little thin. The party says it wants more public transport — trains and buses — with more electrification to cut emissions, and it is also looking to a major tree-planting programme, working with farmers and foresters to promote biodiversity. These are, arguably, very good ideas, but we will need a lot more detail. Especially now we have the requirements outlined in the new IPCC climate report on 1.5° warming to live up to. I will look at that in my next post, but it suggests that up to 60% of global electricity could come from renewables by 2030 and 85% by 2050.
Physics World 10th Oct 2018 read more »
Europe thinks of itself as a global leader in climate change policy, and maybe it is. However, judging by one important metric, its performance is not impressive. The CO2 intensity of energy consumed by EU countries fell by 1% a year on average from the mid-1960s to the mid-1990s. The decarbonisation rate then collapsed precisely when climate change became a policy issue, reaching nearly zero in the mid-2000s. It then rose again, and in recent years has stabilised at 1% a year – no better than before the mid-1990s. Prior to 1990, decarbonisation was largely driven by Europe’s growing use of nuclear power. When the share of nuclear plateaued, the pace of decarbonisation slowed. The trend was reversed when the growth in the share of wind and solar in primary energy accelerated sharply in the late-2000s. But Europe’s generation of zero-carbon electricity must grow massively if it is to further replace power produced using fossil fuels. An added challenge will be the demand for electricity from the transport sector, as it moves away from oil. Solar and wind represent roughly a third of Europe’s zero-carbon electricity today. As most of the continent’s hydro potential has already been exploited, hydropower will not grow, and nuclear – 50% of the zero-carbon total, but expensive and increasingly rejected as unsafe – will likely decline. Europe must grow its share of zero-carbon electricity in order to accelerate decarbonisation. It would require very strong growth of solar and wind even if the share of nuclear was maintained. So the decline of nuclear energy – driven by the phase-out in Germany, and the growing consensus against nuclear in France – will drastically increase the required expansion of renewables. Fighting climate change while reducing Europe’s reliance on nuclear power will be something like running faster and faster up an ever-steeper hill.
IISS 10th Oct 2018 read more »