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Unless you're off the grid, is there any use case for the solar panel you linked? It costs $90, not including the protection circuitry. Even if you pay a lot

Unless you're off the grid, is there any use case for the solar panel you linked? It costs $90, not including the protection circuitry. Even if you pay a lot for electricity (e.g. $0.35 per kWh, like in PG&E service regions), you'd need to be drawing 100W for 7 hours per day, for 365 days, before you break even. I guess realistically you're more likely to break even after 2 years? Do these small panels 'wear out' over time, or will they work for several years?

sweetjuly 4y ago
Solar panels don't really wear out like that. It's possible that severe hail may damage these flexible, less well protected cells but you can easily expect well over a decade out of them. Most residential systems are rated for 25-30 years but can realistically last longer.
- adrianN 4y ago
  Most residential systems have a warranty for 25 years. The manufacturer guarantees that there is no significant degradation for that time. That probably means that they last a lot longer than that.
  - dsfyu404ed 4y ago
    Or it means they enter the steep part of the bathtub curve at 26yr
    - themitigating 4y ago
      Wouldn't it be smarter to have a warranty period end further from a significant increase in the probability of failure?
jack_pp 4y ago
Well if you break even even in 2 years that's still a great investment, beats most other investments out there and there is very little risk
Tade0 4y ago
Ultimately it's a semiconductor, so it's affected by the same aging processes that transistors and LEDs undergo. Actually, LEDs and solar cells are physically the same component, just designed for opposite use cases - much like motors and generators. You can reasonably expect it to lose less than 1% of original efficiency a year, so they should last decades.
- lnsru 4y ago
  I doubt there are many silicon based LEDs. So the both might be made from silicon, but they are definitely not the same component.
bluGill 4y ago
With the range of cargo ebikes it isn't hard to get off grid. Riding a century - 100 miles (200km) - is regular achievement for normal bikes - not e-bikes. Most ebikes only have a range of 40 miles, so just the ability to get 50 miles by charging while riding can be useful. If you go camping, solar puts a campground that if more than 20 miles from you in range: so long as you can recharge while at the campground for a few days you can get back home again. Note that none of the above is about saving money. Other than indirectly because it lets you use a bike for trips that otherwise would require a car, and cars cost a lot more money to own. The above are also uses that I have for an ebike (I don't have one, but those are potential uses making me interested in one), and solar would help make it work out.
- _aavaa_ 4y ago
  Aren't those last 50km going to much more difficult since you're not having to carry the extra weight, and the extra resistance of the electric motor?
  - bluGill 4y ago
    Taking an ebike farther than the batteries range should be considered impossible. While it is possible to ride on a dead battery, the effort isn't worth it. Thus a regular bike has more range than an ebike.
foxyv 4y ago
E-Bike touring would be an excellent use case for this. A lot of people would love to bike tour but don't have the physical ability. I have a friend who was touring on an E-Bike because it made hauling more stuff easier and he would just recharge at each stop. A solar panel would have made a huge difference.

sweetjuly 4y ago

Solar panels don't really wear out like that. It's possible that severe hail may damage these flexible, less well protected cells but you can easily expect well over a decade out of them. Most residential systems are rated for 25-30 years but can realistically last longer.

adrianN 4y ago
Most residential systems have a warranty for 25 years. The manufacturer guarantees that there is no significant degradation for that time. That probably means that they last a lot longer than that.
- dsfyu404ed 4y ago
  Or it means they enter the steep part of the bathtub curve at 26yr
  - themitigating 4y ago
    Wouldn't it be smarter to have a warranty period end further from a significant increase in the probability of failure?

jack_pp 4y ago

Well if you break even even in 2 years that's still a great investment, beats most other investments out there and there is very little risk

Tade0 4y ago

Ultimately it's a semiconductor, so it's affected by the same aging processes that transistors and LEDs undergo. Actually, LEDs and solar cells are physically the same component, just designed for opposite use cases - much like motors and generators. You can reasonably expect it to lose less than 1% of original efficiency a year, so they should last decades.

lnsru 4y ago
I doubt there are many silicon based LEDs. So the both might be made from silicon, but they are definitely not the same component.

bluGill 4y ago

With the range of cargo ebikes it isn't hard to get off grid. Riding a century - 100 miles (200km) - is regular achievement for normal bikes - not e-bikes. Most ebikes only have a range of 40 miles, so just the ability to get 50 miles by charging while riding can be useful. If you go camping, solar puts a campground that if more than 20 miles from you in range: so long as you can recharge while at the campground for a few days you can get back home again. Note that none of the above is about saving money. Other than indirectly because it lets you use a bike for trips that otherwise would require a car, and cars cost a lot more money to own. The above are also uses that I have for an ebike (I don't have one, but those are potential uses making me interested in one), and solar would help make it work out.

_aavaa_ 4y ago
Aren't those last 50km going to much more difficult since you're not having to carry the extra weight, and the extra resistance of the electric motor?
- bluGill 4y ago
  Taking an ebike farther than the batteries range should be considered impossible. While it is possible to ride on a dead battery, the effort isn't worth it. Thus a regular bike has more range than an ebike.

foxyv 4y ago

E-Bike touring would be an excellent use case for this. A lot of people would love to bike tour but don't have the physical ability. I have a friend who was touring on an E-Bike because it made hauling more stuff easier and he would just recharge at each stop. A solar panel would have made a huge difference.