For a total period of 4 months, trials were carried out with 25 Prius PHV vehicles equipped with a device called a data logger that recorded detailed driving data. As reported in the previous issue, 25 company employees and housewives participated in collecting driving data. In addition to the 41 charging units installed in 31 locations such as convenience stores and supermarkets, each of the participants' homes were equipped with a dedicated 200V outlet. The primary use of the vehicles seems to have been over short distances such as commuting to work, shopping trips and transporting family members.
Participants from different ages, gender and usages cooperated and recorded results were more favorable than trials centering on corporate customers conducted thus far. Here we will report on the data gathered from the individual customer trials.
There were variations due to driving distance, but 2 of the participants had more than 200km/L. Even with an average of 44.9km/L, this is a great improvement over previous trials. It can be said that the largest factor in this result is that customers were diligent in frequently charging the vehicles thus extending the EV driving distance.
Fuel Efficiency x EV Driving Ratio x Number of Daily Charges
The graph shows results for daily driving distance and the number of charges. Participant A charged his vehicle nearly every day after driving. By doing so, virtually all of his driving was in EV mode and the surprising result of 249km/L was obtained. Participant C charged almost every day. The HV driving distance became rather far, but even so, a good fuel efficiency of 33km/L was achieved.
Daily Driving Distance and Number of Charges
Driving Condition Results
|Participant A||Participant B||Participant C|
|Driving Distance (km)||2,486||3,131||3,173|
|EV Driving Ratio (%)||94||62||23|
|Frequency of Charges (time/day)||3.4||2.5||1.2||Fuel Efficiency (km/L)||249||57||33|
It has been demonstrated that frequent charging of the vehicle results in the increase in the EV driving ratio, which in turn leads to better fuel efficiency.