According to reports, research teams in Ukraine, Latvia, and Slovakia evaluated the impact of vehicle-integrated photovoltaics (VIPV) on the range of electric vehicles.
The researchers used a 2017 Volkswagen e-Golf 7 series electric vehicle in Kyiv to determine the range of the electric vehicle after a single full charge using solar energy, and compared the results of a fixed VIPV system and a single-axis tracking system.
The team determined that the car has a usable roof area of 1468 mm x 1135 mm. Based on these dimensions, the researchers believe that the roof could accommodate two 120 W solar panels, as well as a 50 MW monocrystalline module from Chinese manufacturer Xinpuguang. The researchers connected three panels in parallel to achieve a maximum power of 257.92 W.
The researchers then calculated the amount of photovoltaic power generated on typical days in January, April, July and October. Based on vehicle test data from the New European Driving Cycle (NEDC) and the U.S. Environmental Protection Agency (EPA), researchers compared the additional range an electric car could travel using solar power. The researchers hypothesized that the solar panels would only charge the EV battery when parked.
The results show that the stationary VIPV system can generate 1587 kWh of electricity in July, and the electric vehicle can travel 7.98 km according to EPA standards and 12.64 km according to NEDC standards. "This is 3.99 percent and 6.32 percent, respectively, of the maximum range when the battery is fully charged," the researchers said. In January, the stationary system produced 291 kWh, which translates to a range of 1.55 km (EPA) and 2.32 km (NEDC), They are 0.77% and 1.16% of the maximum cruising range, respectively.
Tracking systems produce the same amount of energy as fixed systems in summer, but tracked systems produce higher yields in spring, autumn, and winter. The best results came in January, when the electric car could travel 3.01 km (EPA) or 4.52 km (NEDC), corresponding to 1.51% and 2.26% of the maximum possible range on a single battery charge, respectively. The actual advantage may be lower due to a number of limiting factors, the researchers note.
In January, the tracking VIPV system provided an additional 1.46-2.2 km of power to the EV, the researchers said. However, the levelized cost of electricity (LCOE) of this solution is 40% higher than that of fixed-tilt systems. Calculations show that the LCOE for a zero-tilt PV system is $0.6654/kWh. For a system with an inclination of 20 or 80 degrees, the LCOE is $1.1013/kWh. The payback periods for each system were 5.32 and 5.07 years, respectively.
"The sun-tracking roof platform clearly requires a higher initial investment outlay and is more difficult to install," the researchers concluded. "Given the small difference in payback period, drivers of average EVs do not need to adjust the tilt to be satisfied with the system." .”