Renewable Energy. David Elliott

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Renewable Energy - David  Elliott

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safety, so far globally there have been around 192 people killed in accidents related to wind farms, mostly involving occupational accidents during installation or maintenance work, but some involving blade transport (CWIF 2019). By contrast, estimates for deaths associated just with the 1986 Chernobyl nuclear accident, although debated, range up into the thousands and possibly tens of thousands (Ritchie 2017). It is true that emissions from coal-fired plants lead to many more deaths, for example from respiratory illnesses, quite apart from any climate change-related impacts, but arguably the solution is to go for renewables like wind and solar, not nuclear, as an alternative.

      While most renewables have generally low, or even negligible, global environmental/climate impacts, some can have significant local impacts, large hydro in particular. For most other renewables (including small hydro), there are technical options that can reduce local operational impacts on wildlife, such as acoustic bird-scaring systems for wind turbines, and there are also ways to avoid or reduce local social impacts by careful design, siting and operation. Although there are areas of marginal land that can be used, biomass is probably the worst offender in terms of land use. Growing biomass energy crops is inevitably land using. That is one reason why there is now more interest in using biomass in the form of farm and food wastes since that already exists: using it can be part of a move to a lower-impact circular economy. In terms of climate impacts, since the CO2 produced when biomass is burnt is re-absorbed when plants grow, biomass can in theory be near carbon balanced if the rate of use is matched by the rate of replanting. Nevertheless, as I will be illustrating, although it can be a renewed resource, the use of biomass as an energy source may have eco-impacts, depending on the type of biomass and its pattern of production and use.

      There is also the obvious, more general point that there is a need to balance the variable outputs from renewables like wind and solar, the cost of this often being presented as a ‘killer argument’ against them. However, as I will be exploring in detail in subsequent chapters, it is not an insuperable problem. The grid system already handles variations in supply and demand and can be upgraded to continue to do that as more renewables are added, although it may take time to develop and deploy some of the new technologies that will be needed, including storage capacity. The extra cost of grid balancing has been put at maybe 10–15%, or perhaps less, if the proper measures are adopted (Heptonstall, Gross and Steiner 2017): some of the new grid-balancing measures may reduce system costs by matching energy supply and demand better, thus improving overall system efficiency (ICL/Ovo 2018).

      Policy change – the costs of the transition

      In the short term, some say, the changeover to renewables may incur extra costs, perhaps, according to one EU-focused study, adding up to 30% to the total-system cost (Zappa, Junginger and den Broek 2019). However, that view has been disputed in the case of the European Union (EU) (Beam 2019) and is also challenged in many of the global ‘high renewables’ scenarios that have emerged. Instead, it is argued that, as the new system develops, direct and indirect costs should fall since there would be no use of increasingly expensive fossil fuels, and the social and environmental costs of their use would be avoided. As renewable costs continue to fall, and climate threats rise, that view does seem attractive.

      While there are certainly social equity issues to be addressed (McGee and Greiner 2019; Sovacool 2013), and I will look at them later, there are also wider strategic energy perspectives which may present challenges to renewables, such as the belief that other options would be better and cheaper, for example nuclear and fossil carbon capture (Aris 2018).

      Technically, the renewables case is strong. The International Renewable Energy Agency (IRENA) claims that renewable energy, along with energy efficiency, can provide more than 90% of the necessary energy-related CO2 emissions reductions (IRENA 2018). The economic impact case is also good: despite fears about the cost of the energy transition, it may not in fact cost consumers too much. The European Commission (EC) says that, under its proposed renewables-led transition, ‘by 2050, households would spend 5.6% of income on energy-related expenses, i.e. nearly 2 percentage points lower than in 2015 and lower than the share in 2005’ (EC 2018). However, that is speculative, and the EC does include more than just renewables in its proposed mix, as do some other studies. Indeed, although most agree that renewables will boom, some see fossil fuel, and possibly nuclear, remaining as a vital part of the energy mix into the far future (BP 2019; WEC 2019).

      So the question remains: are they right, or can the renewables meet all our energy needs? That may depend on what sort of future global energy system and economy we are looking to create, how rapidly the changes can be made and how we go about making them, issues explored in subsequent chapters.

      The second part of the book moves on from essentially technologically defined issues and options to an exploration of the wider strategic issues and choices, including social change options, asking whether we can and should move

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