I'm thinking of having solar panels to generate electricity. The drawbacks are that I'm afraid if it needs repair, I won't be able to find anyone. Also I'm afraid that the roof is not very accessible. If it is a new house, should the roof have a roof hatch? What can make the system not work?
Modern solar electric panels rarely fail. Because of this, if you would be installing them over a roof that only has a few years left on it, it would be better to redo the roof, first. In the unlikely event that a panel needs to be changed, this can be done in 30 minutes or so, because the panels are mounted on racks, with everything simply plugging together. I have never personally seen a solar installation go bad, but from what I hear, the inverter (a box that goes in next to your electric service panel) is usually what burns out after 5 years, assuming the install was done right in the first place. If you were to call roofers to repair your roof, they would somehow be able to get to your roof, by ladders, or a special truck. Solar installers use the same kind of equipment. They won't have a problem getting up there. A solar electric system is actually a very straightforward thing. No matter who installs it, if there is a problem, another installer should be able to diagnose and fix it.