The roofing industry has been around for a long time and the industry has products to attach items to a roof. The solar industry uses roofing industry approved products
The first time I talked to a home owner about going solar, their first question was "will my roof leak". The answer is of course that it won't leak if installed properly, but it's a valid question. I also have solar on my own home and my wife would kill me if I destroyed our family's property. Of course it doesn't leak, otherwise nobody wanted to go solar. Some accidents or special situations can happen, but in general, a solar installation installed correctly doesn't leak.
Over the years we've installed hundreds and thousands of solar systems on all types of roof surfaces. So why can we be so confident that a solar energy system installed on a roof doesn't leak? Simply because we use industry approved products.
Do you think roofs have lots of penetrations and existing items attached to it? Do roofs have items screws in them, and items going through it or items laying on it? The answer is yes, yes and yes. Look at roofs on google maps and you'll see that most roofs have vents, chimneys, windows and all types of small or big equipment on it. Vents go straight to your roof. So why are you not worried about a vent penetrating your roof with a hole of a few inches wide? Because it's an industry standard practice to install a vent with some proper industry accepted hardware and use proper flashing.
The hardware we use in the solar industry is tested and many times is manufactured by roofing hardware companies that make their products available not just for roofing companies, but also for solar companies. There are also solar specific companies making attachments, but as a solar company we only use trusted brands that have rigorous test like SnapNrack, Ironridge, Ecofasten, Aerocompact and many many more.
Examples: OMG Roofing is a company that provides roofing hardware, and we as a solar company buy their hardware. We use the same hardware as a regular roofing company, we just use it to attach solar panels to a roof.
This is just one example, but we use many types of hardware for all types of roofs. The point is that solar attachment to a roof are no different than other attachments on a roof.
We've spent many hours on roofs and we see HVAC systems on roofs and all types of equipment and penetrations. The last thing we want is having a customer calling us saying they have a leak. We want happy customers and want to improve your home's value not cause damage.
Roofs have penetrations and attachments done with industry accepted roofing hardware. The solar industry uses roofing hardware, too.