Cloud computing is a megatrend in industry digitalization. The virtual power plant (VPP) is especially suited for cloud deployment since it can manage energy resources that are not co-located. However, there is a lack of research in VPP cloudification, mainly related to multi-tenancy, a key technology behind the efficiency benefits of cloud computing. Cloudification is complicated as power systems and distributed energy resources frequently employ interfaces and protocols from an earlier era. In particular, IEC 60870-5-104 is a wellestablished standard for telecontrol in electrical engineering and power system automation applications. This paper proposes a new perspective on VPP interoperability via the application of cloud computing. IEC 60870-5-104 enabled systems are integrated into third-party systems in the cloud. Examples of such third-party systems are the Internet of Things-enabled distributed energy resources or electricity market information systems. This paper proposes a new problem definition of VPPconnected systems through establishing the said third party systems as tenants in a multi-tenant architecture. To define a general industry standards-based system architecture, both the software design methods and cloud computing architectural concepts are applied. An implementation is presented that is ready to integrate into systems in the field.