Project Subjects
Secondary Battery Utilization Technology
Background and Objective
The secondary battery energy storage technology is a key for supply of low carbon electric power, andelectriﬁcation of house demands and transportation ﬁelds, which are very effective against problems caused by
global warming.
One of the aims in this project is to propose a utilization method of the heat pump type water heater andsecondary battery energy storage hybrid system (HP and BES hybrid system) installed in residential house forelectriﬁcation of house demand ﬁeld. And for diffusion of electric and plug-in hybrid vehicles (EV and PHV),
we proposed guidelines for the installation of outlet plugs for normal chargers, and study the optimization of thecharging infrastructure by the trafﬁc simulator. We researched and studied the transition of the diffusion policies
and impact on the markets of EV and PHV to improve the electriﬁcation of transportation ﬁeld.

Main results
1. Development of HP and BES hybrid system installed into residential houses
The prototype of HP hybrid BES system [Q08018] was connected with PV as shown in Fig. 1. We evaluated the energy consumption efﬁciency of this system, and studied an operation method for absorption of excessenergy generated by PV for stabilization of distribution lines. We then evaluated the CO2 emission reduction
effects by high efﬁcient residential energy systems with analysis of the property of hot water demands and theimprovement of the CO2 emission factor of the bulk power system. The HP type water heater system can decrease
more than gas boilers and FC co-generation system [Q09019].
2. Facility guideline for outlet plug of standard charger for EV and PHVPrior to the serious diffusion of EV and PHV, guidelines to be considered, such as ensuring safety, toinstall outlet plugs of normal charger are summarized for ﬁve installation sites; individual house, apartment house,business building, commercial store and parking lot. Recommendations of normal chargers installed indoors andoutdoors are proposed on the basis of requirements of JEAC 8001 which are the electrical engineering regulation
for customers in Japan (Fig. 3) [M09006].
3. Development of Trafﬁc Simulator for Analysis on Charging Infrastructure of EV
Trafﬁc simulation for a model city of population of two million was carried out to analyze the relationship between EV performance, trafﬁc situation, and the requirements of the charging infrastructure for EVdiffusion. The required number of the charging infrastructure was estimated, in case of improvement of the EV
performance and provision of normal charge infrastructure [L09009].
4. Transition of the diffusion policies and their impact on the electric vehicle market in JapanThe objective of this research was to review transition of the diffusion policies and plans and their impact
on EVs in Japan. The targets on the number of EVs were never achieved because of EV characteristics, such as
their short mileage per charge and high price. Although car-sharing services and rent-a-car business were introduced to resolve these issues, targeted userʼs lifestyles and trip patterns were not matched with those services.
[Y09015].

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Environmental and Energy Utilization Technology

Fig.1 Plot type battery energy storage system integrated with heat pump water heater for residential use
connected with PV (left: components, right: system diagram), for validation of energy efﬁciency
improvement under the simulated conditions with daily heat-water demand pattern in a house, andpropose of operation method for absorption of excess energy generated by PV.

Fig. 2 Comparison of CO2 emissions
from residential houses installedwith high efﬁciency water-heatersystems with consideration given
to residential demands.
The amounts of CO2 emission from the residential houses were calculated by simulation
with electricity and hot water demand patterns
in a year. HP type water-heater systems candecrease CO2 emission more than gas boilers
and FC co-generation systems with improvement of the CO2 emission factor of the bulk
power system. The HP type systems candecrease the amount of CO2 emission morethan FC co-generation systems in less than 0.4
kg-CO2/kWh of the CO2 emission factor of thebulk power system.

distribution board

Rated current of an electric wire forbranch circuit must be more than 15A(100V) or 20A (200V).
Method of wiring must be selected
depending on wiring place, and the wiremust be protected against any damage.

Indoor parking

main feeder
Earth Leakage Circuit Breaker
Rated current of an electric wire for branch
circuit must be more than 15A (100V) or 20A(200V).

Free parking
outdoor outlet plug of standard charger
Installation height must be higher than 30cm from the ground.
Plug must be waterproof type or installed in a waterproof container.
The waterproof metallic container must be electrically grounded by
Type-D earthing.

circuit breaker ofbranch circuit

outlet

The plug equipped with earthing connections(D-type earthing) designated by supplier ofelectric vehicle must be usedFig.3 Example of installation of standard charger
Recommendations for indoor and outdoor standard chargers on the basis of JEAC

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