Эротические рассказы

Renewable Energy. David ElliottЧитать онлайн книгу.

Renewable Energy - David  Elliott


Скачать книгу

      The pace of technical development and market adoption has been startling, taking even enthusiasts by surprise (for photovoltaic solar especially), and can be contrasted with the slow pace of development of the rival technologies, nuclear (Pearce 2017) and carbon capture and storage (Simon 2017).

      As the head of the UK government’s advisory Committee on Climate Change put it, they had initially been ‘overly optimistic about cost falls in some other technologies – nuclear for example’, but for renewables ‘innovation has been the key – driven by policy – in ways that we did not fully expect ten years ago. Globally, a clear goal to decarbonise, with co-benefits of improved air quality in cities, has stimulated commercial innovation’ (Stark 2019a).

      It is relatively easy to provide specific counters to these challenges and to the assertion often made that ‘nuclear is a better bet than renewables’. For example, on cost, it is clear that many existing nuclear plants in the United States are having to close because they are no longer competitive (Abdulla 2018) and that, globally, few new nuclear projects are going ahead. By contrast, renewables are winning out economically in most countries (WNISR 2019).

      On 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


Скачать книгу
Яндекс.Метрика