That's an easy one, yes, unless the rain does it for you.
In the winter it may help if you live in a region where it snows a lot if you can actually reach your panels should they get covered with snow overnight.
In most latitudes your solar panels will be at a sufficient angle to let the rain do its work. If you are at or near the equator it's a different story, some regular cleaning will be necessary.
A better question is 'should solar panels be tracking the sun', and the answer to that one is it depends.
I've lived in Northern Ontario in a house exclusively powered by sun and windpower and even though we had our panels tracking the sun I doubt I would do it again that way.
The reason is that a tracker is a finicky device, fragile and costs a lot of money. Roof mounted panels are much less susceptible to storm damage. The downside is the decreased power, but you can make up for the by investing the money you would otherwise invest in a tracker in several more panels.
Fancy trackers that track on two axis are even more expensive and error prone, but the convenience of not having to do a seasonal adjustment is worth it for some.
Here in the suburbs of a major metropolitan area, and with a lot of agricultural activity further upwind, I find that my car windows develop a film that rain does not remove. Some of the film may be from vegetation (tree sap, etc.), but I can wash the windows and then park in an open parking lot and a driveway with no canapy, and still experience the film.
I wonder whether there are similar issues for solar panels, not solved by rain.
EDIT: Should have read the linked post, first. Rain works well enough for them.
In the winter it may help if you live in a region where it snows a lot if you can actually reach your panels should they get covered with snow overnight.
In most latitudes your solar panels will be at a sufficient angle to let the rain do its work. If you are at or near the equator it's a different story, some regular cleaning will be necessary.
A better question is 'should solar panels be tracking the sun', and the answer to that one is it depends.
I've lived in Northern Ontario in a house exclusively powered by sun and windpower and even though we had our panels tracking the sun I doubt I would do it again that way.
The reason is that a tracker is a finicky device, fragile and costs a lot of money. Roof mounted panels are much less susceptible to storm damage. The downside is the decreased power, but you can make up for the by investing the money you would otherwise invest in a tracker in several more panels.
Fancy trackers that track on two axis are even more expensive and error prone, but the convenience of not having to do a seasonal adjustment is worth it for some.