Is the payback period important for solar panels?
Is there such a thing as payback time for solar panels? Portable solar panels are a source of DC electricity. They provide power to the standard DC appliances. Solar panels can be the power source of portable battery chargers (and wireless device chargers). Solar panels can be used for running some DC equipment during the daytime using power from the sun. There are portable solar panels available at a small scale that can use as a personal phone charger. Similar but larger portable solar panel devices can run an RVportable home site. The first type of portable solar panel might be a 20W–30Wpanel. Then, the second type of portable solar panel would be a folding set with say three 100w panels.
The payback period is only one factor in the list of considerations of comparison. One usually considers the most viable option that is available and choose that. We assume that economically rational people would select options from among the least costly items providing the highest value output. You might look at the payback of portable batteries for maintaining the charge. Compare that against the cost of solar panels and rechargeable batteries. One amortises the cost of batteries for the number of batteries over the equivalent period of using the different batteries. How many batteries will be paid for in the duration of using the solar charger? You might consider how long in time would it take to pay for the solar panel option against using batteries.
What is important to compare?
There is little point in making some comparisons. A fixed installation electrical power set-up of a cabin is expensive compared with the cost of portable solar panels. Portable solar panel voltages are low and not effective for running a home. You could do calculation checks for running a portable generator and compare the cost of using portable panels. To make the comparison fair, there would need to be an added cost. You need a battery power bank to store electricity to use at night-time.
Maybe compare solar panels for a charging station of one or two lithium batteries with other methods. One could check the cost of a portable generator and fuel to charge the same batteries. The choice would be the cost of the solar panels versus the cost of the generator for the same job. The payback period is an important economic rationale indicator but not the whole story.
Again, solar panels need to be positioned into the sun, oriented at the right angle and kept clear from shadows. Solar panels only operate during daylight. They are quiet and pollution-free. The generator needs fuel to do its job. It can be used after hours but it is noisy. Generators need fuel and maintenance, so essentially, a choice will depend on personal preferences.