Toyota City Low-Carbon Verification Project Event [Getty Images]

The Home Energy Management System (HEMS) control panel shows the usage of energy in the kitchen of a model house for the Toyota City Low-Carbon Verification Project in the Higashiyama district of Toyota City, Japan, on Thursday, June 30, 2011. The Toyota City Low-Carbon Society Verification Promotion Council, an organization of 26 entities, including Toyota City and private companies, has completed model smart houses in the Higashiyama and Takahashi district of the city for testing energy-management systems and has started trial operations under the verification project for the establishment of a household and community-based low-carbon city in Toyota, Aichi Prefecture. Photographer: Kimimasa Mayama/Bloomberg via Getty Images

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