With increasing urbanisation, Yokohama is experiencing fast growth, presenting challenges in terms of energy use, mobility, air pollution and an overall increase in greenhouse gas (GHG) emissions. YSCP strives to more effectively manage energy use and mitigate climate change through energy management systems. The city’s action plan sets the target of an 80% CO2 emissions reduction by 2050. The project is designed to engage citizens and stakeholders as a key factor of successful implementation. Aiming to create an energy-circular city excelling in the areas of disaster prevention, environmental friendliness and economic strength, the city established a new public-private partnership, the Yokohama Smart Business Association (YSBA), to formulate business models to take projects from implementation to verification using new technology cultivated in YSCP.
Implementation of YSCP has reduced CO2 emissions by 39,000 tons (a 29% reduction). 37MW-worth of solar panels have been introduced, HEMS have been installed in 4,230 households and 2,294 next-gen vehicles have entered operation. The city government has certified 69 companies, some of them local, to install HEMS, increasing citizen uptake and trust in the programme.
A demand response pilot brought demand forecast errors under 5% and reduced energy consumption by up to 15.2% in 3,500 households and up to 22.8% in 29 buildings. HEMS allows citizens to save energy through easy behavioural changes, promoting low-carbon, comfortable lifestyles.
The Yokohama City University Medical Centre and a Minami Ward government building began energy cooperation in January 2016 through practical implementation of comprehensive management of heat and electricity via BEMS. A cogeneration system was installed using city gas as fuel for heat and electricity, and the BEMS allowed for optimising control of the existing central monitoring equipment and energy supply.
Yokohama has been working to integrate energy use between its garbage incinerators and adjacent wastewater processing plants for around 20 years. Both facilities generate electricity using the digestion gas produced during the sewer sludge treatment process and decrease dependence on purchased electricity by using electricity generated in the garbage incineration process. Incinerators can also sell excess generated energy, providing further income and promoting local power generation.
Effective integrated energy use at the medical centre and ward building is expected to cut costs by $397,000 (USD) per year and CO2 emissions by 5.5%. YSCP will contribute to Yokohama’s CO2 emissions reduction targets of 16% by 2020, 24% by 2030 and 80% by 2050 (compared to 2005). The implementation arm of YSCP, YSBA, has the overarching objective of creating integrated energy management of heat and electricity on both the demand and supply sides by linking with related city projects aiming for low-carbon urban development.
YSCP results are being used by private companies to develop products and accumulate knowledge. For example, the storage battery control technology in the CEMS pilot is being used to manage frequency fluctuation and balance electricity supply and demand in several substations of Tohoku Electric Power. As such, the project is predicted to have broader impacts beyond the city borders.