A
proven electric-only range of yuramobile in far from excellent conditions, but with
aggressive use (summer, poor roads, the skies mostly overcast, a
decent acceleration, near top speeds, a few traffic lights, but with
a gentle braking) is 170km. An estimated electric-only range in excellent conditions, but with aggressive use (good roads, summer,
clear skies, aggressive acceleration, little braking, the PV panel is
exposed to sun for the whole day) is about 200-230km. An estimated
electric-only range in excellent conditions with normal use (good
roads, few stops, summer, clear skies, gentle acceleration, gentle
braking, few stops, flat roads and the PV panel is exposed to sun for
the whole day) is about 230-250km.
If the vehicle is positioned horizontally, it's summer (the Northern Hemisphere) and the weather is sunny, you can easily get 1-1.5kWh of energy to batteries over a day thus being able to ride for more than 100-150km on that solar input alone. When you stop and make the panel face the sun at a right angle, you can expect the battery to get around 150W/h, thus giving you around 15 km of electric-only range.
If you pedal with about 100W of output, especially while accelerating gently, you should expect the range to easily reach 400 km (the skies overcast, no strong headwinds). Once I drove in A7 270 km in a single day without any electric assist (summer and excellent roads). Thus, accounting for the extra weigh of PV and electric apparatus together with worse aerodynamics of yuramobile compared to unmodified A7, a 400-450 km range is attainable on yuramobile without much sweat (if I find good roads, I'll check this, but am afraid I need to leave my country to do that). For those in doubt, I'll wager a few $$ that I can make 500 km over a day in yuramobile;) (summer, sunny day, good and relatively flat roads).
Tips to extend range
1.Keep
the current draw from the traction battery low by accelerating gently and/or providing more pedalling input.
2. Use brakes as little as possible so that the hubmotor slows the vehicle by charging the battery.
N.B. The regen function of the motor is quite limited so please keep the brakes well maintained and don't hesitate to apply them when needed;) (I'm a big fun of coasting but there is a limit to that).
3. The charging/discharging of the traction battery consumes energy just for the process hence it makes sense to ride while the sun is high up getting the current from the PV panel straight to the motor. The fewer transformations of energy, the more efficient the whole system (this applies to humans with a few reservations;).
4. The lower the PV panel's temperature, the more power you get from the Sun. Thus a bit of cooling that the oncoming air provides to the PV panel while you are moving is beneficial. But there is a trade off, since when the panel is horizontal it gets less power from the sun.
5. Even if the sky is heavily overcast, the PV panel still charges the battery or provides about 30W straight to the motor if it is on.
6. The warmer the air, the less there is a drag on the vehicle, but the PV panel's efficiency drops with its temperature rising. But in the end, the sunnier it is, the more charge you get from the sun, even if the panel heats up to 50-60 C.
7. A7 isn't as air-dynamically sophisticated as WAW, Quest or DF (especially the latter), but it still makes sense to keep the profile low and not to ride at the top speed.
