*3.3. Test Results Analysis and Comparison*

The test results indicate that the optimal solutions for BEVs and ICEVs are quite different. The optimal solutions for BEVs and ICEVs when decelerating upstream of an intersection are summarized in Table 1. For downhill roadways, BEVs require longer deceleration times to accumulate more regenerative power to minimize overall energy consumption when traversing the intersection. Conversely, ICEVs need the maximum deceleration level (minimum deceleration time) to minimize overall energy consumption. For uphill approaches, BEVs need to minimize deceleration time to reach the approach stop line at maximum speed, saving energy downstream while accelerating back to the roadway speed limit. Contrarily, the optimum ICEV deceleration level is typically in the mid-range to minimize overall energy consumption. The comparison demonstrates that the energy-optimum solution for BEVs is different from that for ICEVs, as they consume energy differently. The findings in the case study also prove that previous studies, which only considered the optimization of vehicle acceleration and deceleration movements and ignored the specific vehicle energy model, may not correctly compute the energy-optimal eco-driving solutions for different types of vehicles.

**Table 1.** Optimal solutions for BEVs and ICEVs Eco-CACC-I systems when the vehicle needs to decelerate to traverse a signalized intersection.

