Oh, how perfect that would be – riding an ebike without ever having to worry about the battery, because it’s constantly recharging. Goodbye, range anxiety. At least during the day, the sun hovers above us as a virtually unlimited source of energy that could be tapped for this very purpose. This is exactly what the Phosgo Go5 solar ebike does. According to the manufacturer, it’s even the world’s first production-ready model of its kind. Despite its large solar panels, the charging speed is still slower than that of a standard charger. On the other hand, you’re travelling in a way that’s as sustainable as is practically possible, and you can keep riding whilst it charges.
1. Solar ebike features wheels with integrated solar panels
2. Consistent solar power output in varying weather conditions
3. Special design makes solar panels particularly robust
4. High-tech and a few simple screws
5. Phosgo Go5 charges in almost any situation
6. How far does the solar ebike go with the extra power?
7. Design vulnerable to strong winds
8. Phosgo Go5 with automatic gearing and high load capacity
9. E-drive from well-known brands
10. Digitally up to date
11. Two models and one chance to save big
1. Solar ebike features wheels with integrated solar panels
What may sound like science fiction to some we have already seen in the past in concepts such as the Zendure e-cargo bike or the Løkka and Inga from Infinite. This is now actually becoming a reality. With the Go5, Phosgo is launching a solar ebike that charges the ebike battery using the sun’s energy whilst riding and when parked. Four solar panels integrated into the wheels generate a total of 200 watts. This power can be utilised by the ebike system – comprising the motor, battery, control unit and display – along with integrated components such as the lights and the electronic gearshift. The manufacturer is currently offering the first production models on Indiegogo as part of a crowdfunding campaign for the markets in Europe, the USA and Australia. Thanks to early-bird discounts, prices start from just 1,899 US dollars.
2. Consistent solar power output in varying weather conditions
Despite the price sounding pretty reasonable, the solar modules appear to offer everything one would expect from high-quality modules designed for outdoor use these days. Their appearance is reminiscent of the rims of an aero wheelset. Phosgo has laminated them into the wheels. As back-contact modules (BC modules), the conductor paths of their individual solar cells are connected on the rear side. This allows the electricity generated to be drawn off solely from the rear of the cells. At the same time, it means no metal leads are required on the front. Not only does this look better, but it also increases the light output.
Inside the frame is a Maximum Power Point Tracking controller, or MPPT controller for short. It modulates the higher input voltage of the solar modules, thereby maximising the charging current. This ensures the modules operate as efficiently as possible and that the power they generate is utilised to the full. The result is a relatively constant charging current, regardless of whether it is slightly overcast or completely shaded, or at what angle the sun’s rays strike the solar modules.
3. Special design makes solar modules particularly robust
Round. Slightly curved. Designed to withstand weathering and certain mechanical stresses. This set of requirements is quite specific for solar cells. The manufacturer therefore relies on an equally specific design. The solar module is reinforced and encapsulated in multiple layers. This enables it to withstand long-term outdoor use. The reinforcement is designed to prevent hidden micro-cracks from forming in the solar cells. In this way, Phosgo achieves a level of stability for the entire module structure that can withstand impacts of protection class IK05 without damage. A wear-resistant, transparent ETFE outer layer, which allows UV light to pass through, offers additional protection against abrasion and scratches. Phosgo expects this design to withstand the vibrations, impacts and other everyday wear and tear that we are familiar with from cycling.
4. High-tech and a few simple screws
The solar modules are manufactured in modern factories at several locations worldwide. However, most of the production takes place in Dongguan, in southern China – interestingly, in the very city where Gobao is based. On the respective production lines, the BC solar cells are soldered together to form connected strings. This is followed by the lamination of the connected cell strings with protective layers. Finally, lasers cut the laminated, flexible module to size, forming a circular module for the solar ebike.
Fitting the modules to the ebike’s wheelset, on the other hand, still appears to be carried out largely by hand at present. Two modules are attached to each side of every wheel. Several fixing screws hold them together. This means a total of four modules are distributed across the front and rear wheels. Thanks to this modular design, the solar modules can be fitted, removed and maintained without altering the wheel’s original spoke lacing. Phosgo hopes this will enable it to maintain the necessary spoke tension, flexibility and handling characteristics.
5. Phosgo Go5 charges in almost any situation
Once installed on the ebike, the sun’s energy is fed from the solar module into the ebike system via a proprietary conductive hub and the solar controller. What happens to it there depends on whether the ebike is currently parked or in motion. When it is not in use, all the solar energy flows into the ebike battery. When you are riding, however, it powers the motor alongside the energy stored in the battery, meaning the ebike battery discharges more slowly.
6. How far does the solar ebike go with the extra power?
What energy output can be expected from such a system under real-world conditions? That is the question by which the Phosgo Go5 will ultimately be judged. As expected, the manufacturer is well aware of this. That is why it has put its production model through practical testing and published the relevant data. In one of the tests, the ebike was ridden for a distance of just over ten kilometres, then left in the sun for four hours, before being ridden back to the point of departure. The total distance covered was therefore around 21 kilometres. The ebike’s 720 watt-hour battery was 60 per cent charged at the start. Whilst stationary, the charge level rose from 53 per cent to 73 per cent thanks to the solar function. On arrival, the team recorded a battery level of 66 per cent.
According to Phosgo’s calculations, the 20-percentage-point increase in charge level whilst stationary corresponds to a capacity of approximately 144 watt-hours – or, expressed in terms of range, around 29 kilometres at a consumption rate of just under five watt-hours per kilometre. Four hours of charging for 20 per cent more capacity doesn’t sound particularly impressive at first. However, the electricity was completely free and nobody needed to bring a charger with them.
Just a single charge per month
To illustrate this better, Phosgo also presents a simple calculation. In this scenario, a person commutes a distance of approximately 32 kilometres daily and regains up to around 27 kilometres of range over the course of the day. On a daily basis, the 720 watt-hour battery therefore loses five kilometres of range on balance from its estimated range of 145 kilometres. According to this calculation, it would take just under 30 days before the ebike battery would need recharging. Depending on the specific conditions – such as sunlight, temperature, route profile, selected assistance level, rider’s weight and so on – the result will understandably vary.
Nevertheless, it is clear that the Phosgo Go5, with its solar technology, can significantly extend the ebike’s range. However, you will still need a charger. And sooner than calculated here, in a typical autumn week in Central Europe with shorter days and the odd spell of bad weather. Besides, in our part of the world, whose ebike is usually parked outdoors most of the time? That, too, limits the charging capacity.
7. Design vulnerable to strong winds
Furthermore, the question arises as to how an ebike with two disc wheels will handle in windy conditions. It is not without reason that such a wheelset is generally only used in professional cycling during time trials, when the weather is suitably calm. Phosgo emphasises that its Go5 would remain stable and controllable even in strong winds. For example, the curved surface of the module would channel the airflow around the wheels, thereby reducing drag and improving the ebike’s riding stability. However, anyone who has ever ridden a bike in strong winds with rims 50 millimetres or higher will confirm that strong crosswinds and sudden gusts are by no means to be taken lightly. In terms of wind resistance, we consider this model more as a fair-weather bike.
8. Phosgo Go5 with automatic gearing and high load capacity
If you ignore the wheels with the solar panels, what remains is a rather unassuming ebike. Phosgo produces the aluminium frame in both a diamond frame and a low-step design. Both versions will be available in a single frame size only. According to the manufacturer, this is suitable for people between 168 and 190 centimetres tall, or between 170 and 193 centimetres tall respectively.
A suspension fork with 110 millimetres of travel, combined with a suspension seat post, ensures a comfortable ride even on bumpy surfaces. Thanks to permanently fitted lights, mudguards, a rear rack and a side stand, you’ll be well equipped for road use. The Wheeltop eight-speed automatic derailleur on the Go5’s top-of-the-range model, the Phosgo Go5 Ultra, deserves a special mention.
Given a total weight of around 31 kilograms, it’s not entirely easy to recommend this ebike for everyday urban use. You’ll need to be in pretty good shape if you want to carry the Go5 up stairs or onto a train. After all, the maximum permitted total weight is 200 kilograms. This means that riders, together with accessories and luggage, can weigh in at around 170 kilograms. That’s quite a lot.
9. E-drive from well-known brands
The mid-drive motor chosen by Phosgo is made by Bafang. We cannot say with absolute certainty whether the Bafang M430 will actually be the motor fitted in the versions of the Go5 intended for sale in Europe. Its rated continuous power of 750 watts, as stated on Bafang’s website, would be too high for that. However, it is likely that the ebike manufacturer can have this reduced. The maximum torque of 120 Newton metres would, in any case, be more than sufficient.
We have already mentioned the battery’s capacity of 720 watt-hours. The battery is manufactured by LG and therefore comes from South Korea. In the more affordable Phosgo Go5 Pro, the manufacturer opts for a smaller battery. Its capacity is just 480 watt-hours.
10. Digitally up to date
When looking at the digital features of the ebike system, we can mentally tick off a number of features that today’s solutions offer even in this price segment. Phosgo uses 4G and Bluetooth for connectivity and communication within the system. An integrated GPS is also included. This allows you to track the ebike’s location in real time, record your rides, use navigation and even activate a motion alarm in the app. You can control the associated digital anti-theft protection remotely.
11. Two models and one chance to save big
The current Indiegogo campaign features two versions of the Phosgo Go5 – the Phosgo Go5 Ultra and the Phosgo Go5 Pro. Essentially, the two differ in just two details. The higher-end Phosgo Go5 Ultra features an automatic electronic derailleur and a battery with a capacity of 720 watt-hours. The entry-level model, the Phosgo Go5 Pro, features a mechanical gear system and a 480 watt-hour battery. This results in a price difference of 1,000 US dollars. The manufacturer has announced a price of 3,799 US dollars for the Phosgo Go5 Ultra, whilst the Phosgo Go5 Pro is set to cost 2,799 US dollars. Anyone wishing to secure one of the models as part of the crowdfunding campaign can make significant savings, bringing the prices down to a maximum of 2,499 US dollars and 1,899 US dollars respectively.
Phosgo Go5 at a glance
- Models: Phosgo Go5 Ultra, Phosgo Go5 Pro
- Frame: Aluminium
- Suspension fork: Air suspension fork, 110 mm
- Motor: Bafang M430
- Battery: LG 720 Wh, LG 480 Wh
- Display: 1.9”
- Drivetrain: Wheeltop EDS Shimano
- Brakes: hydraulic disc brakes, 180 mm
- Weight: from approx. 30 kg
- Maximum permitted total weight: 200 kg
- Prices: from 2,799 US dollars (RRP)
Pictures: Phosgo