Since the steady growth of the German biogas sector, its sustainability is subject to constant scrutiny, especially economic and environmental sustainability. Public concerns about sustainability of biogas started with the issue of energy crop cultivation in the 2010s. To steer sustainability in the biogas sector, a broad variety of regulations and acts were enacted, mainly via top-down legislation making. But in order to govern sustainability in every step of the value chain, involvement of numerous stakeholders in the biogas sector is necessary. This paper will address the question: What are the perceptions of the relevant stakeholders in the biogas sector regarding various sustainability issues and what are their expectations? Following an instrumental approach, three steps were initially undertaken for the systematic analysis of the stakeholder landscape, namely (1) stakeholder identification, (2) stakeholder categorization, and (3) investigation of stakeholder relationships. In addition, a theoretical mapping was performed to identify those actors, who most likely impact the implementation of biogas value chains, or are strongly affected by this implementation. These were then subject to surveys via questionnaires and semi-structured interviews to gather information on their sustainability governance perception. Results indicate that key players are farmers and biogas associations due to anchoring in agricultural sector, along with environmental non-governmental organizations (NGOs) and policy makers. Furthermore, the surveyed stakeholders agree on regulating sustainability at national level, while tending toward neutral or even disagreeing for the regulation of sustainability at local and international level. They also agree that certification and standards can be an effective tool for compliant sustainability governance. This study revealed a clear expectation gap regarding the transfer of the current energy legislation in a bio-economy and how sustainability shall be steered then (mandatory/voluntary and local (national) level/international level). The surveyed stakeholders expect transparent and clear rules from the government to steer sustainability that they currently do not perceive with regard to the expectation gap. In order to integrate the different stakeholders in the bio-economy development instead of confronting them with opaque legislation making, it is important to clearly communicate not only the opportunities but also the requirements that come along with the implementation of a bio-economy.

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利益相关者对德国沼气行业可持续性治理的看法

由于德国沼气行业的稳定增长，其可持续性受到不断审查，尤其是经济和环境可持续性。公众对沼气可持续性的关注始于2010年代的能源作物种植问题。为了引导沼气行业的可持续发展，主要通过自上而下的立法制定了各种各样的法规和法案。但是，为了在价值链的每个步骤中控制可持续性，沼气行业中众多利益相关者的参与是必要的。本文将解决以下问题：沼气行业相关利益相关者对各种可持续性问题有何看法，他们的期望是什么？按照工具性的方法，最初采取了三个步骤来对利益相关者格局进行系统分析，即（1）利益相关者识别，（2）利益相关者分类和（3）利益相关者关系调查。另外，进行了理论映射以识别最有可能影响沼气价值链实施或受此实施强烈影响的那些参与者。然后通过问卷调查和半结构化访谈对这些人进行调查，以收集有关其可持续性治理观念的信息。结果表明，由于参与了农业部门，农民和沼气协会是主要参与者，还有环境非政府组织和政策制定者。此外，接受调查的利益相关者同意在国家层面规范可持续性，同时倾向于中立，甚至不同意地方和国际层面的可持续性监管。他们还同意，认证和标准可以成为合规的可持续性治理的有效工具。这项研究揭示了在生物经济中现行能源法规的转移以及随后如何指导可持续性（强制性/自愿性和地方（国家）级/国际级）方面存在明显的期望差距。被调查的利益相关者期望政府制定透明，清晰的规则，以指导他们目前在期望差距方面尚未意识到的可持续性。为了使不同的利益相关者融入生物经济发展中，而不是使他们面对不透明的立法，