Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage

由二氧化碳排放量增加引起的气候变化，主要是燃烧化石燃料发电，是社会最紧迫的关切之一。目前，英国约90%的能源需求由化石燃料满足，在未来几十年内，化石燃料可能仍将是主要的能源来源。发展我们对旨在减少二氧化碳排放的一系列战略的利弊的理解是至关重要的。在风能、波浪和太阳能可再生能源以及碳捕获和储存(CCS)等现有战略中，没有一个是没有潜在问题或限制的。简单地说，CCS的概念是在发电过程中捕获二氧化碳，并将其永久存储在陆地或海面下的深层地质结构中。如果CCS成功，就可以利用现有的化石燃料储备，同时开发低二氧化碳排放的新发电形式。有几个项目已经在有限的规模上成功地展示了捕获或储存，因此可以确定，技术挑战是可以克服的。研究还表明，地质结构总体上是坚固的，可以长期储存(例如，石油矿藏仍留在地质地层中)。然而，地质结构复杂，天然地下气藏已知在地表出气。因此，在不了解泄漏的可能性和可能发生的影响的严重程度的情况下制定全面的CCS方案是不负责任的。这项建议的目的是大大提高对CCS系统泄漏可能对生态系统造成影响的规模的了解，并使对CCS的全面风险评估成为可能。在英国，储存二氧化碳的主要地点将是北海的地质构造，我们的研究集中在对海洋环境的影响上，尽管我们的工作也将与所有地质构造相关。迄今为止的研究表明，假设的大规模泄漏将显著改变沉积物和水的化学成分，因此一些海洋生物将变得脆弱。目前还不清楚的是，物种的弹性有多大，以及给定的泄漏会产生多大的影响。我们的项目将首次调查真正的海洋群落(包括沉积物内和沉积物上方)对严格控制的小规模人工泄漏的反应。我们将研究化学和生物效应，重要的是调查恢复所需的时间。我们将能够将影响的足迹与已知的二氧化碳投入率联系起来。结果将使我们能够开发和测试可应用于其他情景的流动和影响模型，我们将评估一些监测方法。该项目还将调查通过地质构造的流动的性质，以使我们了解上升的二氧化碳羽流在突破水库时的扩散情况。这里提议的工作将在理解和科学工具方面取得重大进展，以形成CCS风险评估和对泄漏的生态影响的量化知识。我们将开发可以预测泄漏从水库到生态系统的转移、命运和影响的模型工具，这些工具可能会在规划特定的CCS操作时应用。我们工作的一个重要成果将是建议最佳监测战略，以确保及早发现泄漏。我们将与来自行业、政府和公众的有关各方合作，确保我们提供的信息是可访问和有效的。

Climate change caused by increasing emissions of CO2, principally the burning of fossil fuels for power generation, is one of the most pressing concerns for society. Currently around 90% of the UK's energy needs are met by fossil fuels which will probably continue to be the predominant source of energy for decades to come. Developing our understanding of the pros and cons of a range of strategies designed to reduce CO2 emissions is vital. Of the available strategies such as wind, wave and solar renewables and Carbon Capture and Storage (CCS) none are without potential problems or limitations. The concept of CCS simply put is to capture CO2 during the process of power generation and to store it permanently in deep geological structures beneath the land or sea surface. If CCS is successful existing fossil fuel reserves could be used whilst new forms of power generation with low CO2 emissions are developed. A few projects have been successfully demonstrating either capture or storage on limited scales, so it is established that the technical challenges are surmountable. Research is also demonstrating that the geological structures are in general robust for long term storage (for example oil deposits remain in place within geological strata). However geological structures are complex and natural sub surface gas deposits are known to outgas at the surface. Consequently it would be irresponsible to develop full scale CCS programmes without an understanding of the likelihood of leakage and the severity of impacts which might occur. The aim of this proposal is to greatly improve the understanding of the scale of impact a leakage from CCS systems might inflict on the ecosystem and to enable a comprehensive risk assessment of CCS. The main location of stored CO2 in the UK will be in geo-formations under the North Sea and our research concentrates on impacts to the marine environment, although our work will also be relevant to all geological formations. Research to date has shown that hypothetical large leaks would significantly alter sediment and water chemistry and consequently some marine creatures would be vulnerable. What is not yet understood is how resilient species are, and how big an impact would stem from a given leak. Our project will investigate for the first time the response of a real marine community (both within and above the sediments) to a small scale tightly controlled artificial leak. We will look at chemical and biological effects and importantly investigate the recovery time needed. We will be able to relate the footprint of the impact to the known input rate of CO2. The results will allow us to develop and test models of flow and impact that can be applied to other scenarios and we will assess a number of monitoring methods. The project will also investigate the nature of flow through geological formations to give us an understanding of the spread of a rising CO2 plume should it breach the reservoir. The work proposed here would amount to a significant advance in the understanding and scientific tools necessary to form CCS risk assessments and quantitative knowledge of the ecological impacts of leaks. We will develop model tools that can predict the transfer, fate and impact of leaks from reservoir to ecosystem, which may be applied when specific CCS operations are planned. An important product of our work will be a recommendation of the best monitoring strategy to ensure the early detection of leaks. We will work alongside interested parties from industry, government and public to ensure that the information we produce is accessible and effective.