Publisher Summary This chapter discusses the concept of the interconnection of homes with energy networks. Homes can share their tools through networks for flexible and efficient operation, such as the reduction of partial load and start-stop operations. The chapter proposes an interconnection of homes via electricity, heat, and hydrogen networks to allow consumers to interchange energy. An experimental system and a PC-based simulator are constructed to evaluate the proposal. Interconnection can provide considerable CO2 mitigation and energy conservation. An experimental system is constructed by connecting a server PC, which is assumed to be the supervisor of energy networks and four systems having same configuration. Each system includes a fuel cell with a capacity of 1.2 kW, a hydrogen supply, an electronic load device, and an instrument and control system incorporating PCs. The simulator provides complex and expanded simulations and information. It can expand to a new to a large model. The experimental systems and PC simulators improve the analysis of the effects of, schemes for, and rules and protocols for energy interchange and operation of equipment.