GetOffYourGas wrote: GRA wrote:https://www.greencarcongress.com/2018/10/20181031-hmg.html
. . . Electricity-generating solar panels will be incorporated into the roof or the hood of vehicles, and will support internal combustion, hybrid and battery electric vehicles with additional electrical power, increasing fuel efficiency and range.
The solar charging technology is being developed to support the vehicle’s main power source, improving mileage and reducing CO2 emissions. The system will have the capability to charge the batteries of electric and hybrid vehicles, as well as those of internal combustion engine (ICE) vehicles, helping to improve fuel efficiency.
Hyundai Motor Group is developing three types of solar roof charging systems: . . . .
The first-generation system, which will be applied to hybrid models, is created out of a structure of silicon solar panels that are integrated into a standard car roof. This system is capable of charging 30 to 60 percent of the battery over the course of a normal day, depending on weather conditions and other environmental factors. <snip>
Obviously they are talking about the 12V battery here. Since most car batteries hold less than 1kWh, that means less than 300-600Wh per day. Assuming about 4h of equivalent direct sunlight, that's 75-150W. Not a whole lot. Of course my numbers are guesses, but it gives you a ballpark idea.
I fail to see how a system that generates 0.6kWh/day or less can make a meaningful impact on fuel efficiency or range.
As I read it, the bolded
section refers to the hybrid drive battery, and they are typically a bit over 1 kWh( IIRR the Prius was around 1.3kWh (forget which gen.), but that was total, not usable, and a hybrid battery is designed for max. power, not max. energy. Naturally, there will be a converter to run 12V loads.
As for range effects, you want to be able to run the DRLs, fan, infotainment system/computers, maybe seat/steering wheel heaters and provide some or all of the power for a heat pump (In the Prius Prime, "Toyota and Denso say the system uses 63 percent less energy than a traditional heating system, and helps extend the car's battery range up to 21 percent in cold temperatures"), plus (while the car is parked) exhausting hot air without running the battery down, thus reducing the A/C load on start-up while keeping the drive battery's full energy available for driving.
So, while a roof or hood-sized PV module will not be able to provide a lot of power, it will provide a small but sometimes significant range boost, especially when (in an HEV/ICE) you don't have to drive an alternator with a belt. This is far more useful than the token, tiny PV module on LEAF SVs. Fully covering all the car body panels (i.e. also doors/fenders) with PV would increase the aux. loads that could be handled, and would even allow intermittently-used cars (like mine) to get most or all of their charging direct from the sun, not that that's likely to be common. OTOH, any extra weight due to the modules would partially offset some of the gain.