Based on basic passenger car (EG6042K and EG6062K), put a build-in solar panel on the top. It can give 10kms range when the sunshine is good enough. And also it's good for the battery as it will keep charging the battery. Below is the basic specification:

Passenger capacity:  4
Motor Power (KW):  3

Solar Power: 115W
Battery Voltage (V):  6
Battery Quantity (pcs): 8
Range (loaded) (km): 80+10
Max. speed (km/h): 33
Minimum turning radius (m): 4
Max. climbing ability (loaded): 20%
Max. movement after brake: ≤4m
Overall dimensions: 2940x1400x1730mm
Max. loading weight: 360kgs
Net weight: 680kgs