CCD sensor camera as backup?

I have a Nikon d7000 camera, is d70 which is a CCD sensor a good backup?
People say ccd's don't heat up quickly is it better to take long exposure shots and time lapses with this camera?

Your D7000 is equiped with thermal sensors which warn you when the temperaturereaches 'this' point & shuts off when it reaches 'that' point

In effect it has a built in mechanism to prevent burnout, or any permanent damage
So does every modern DSLR

I would enjoy my photography & not worry about sensor overheat if I were in your place
I would think about a CCD sensor, or otherwise if I were to repeatedly fail or get frustrated with overheating issues during a project

As long as you do not use live view, the camera will perform with no sensor heat problems.

It is only when a person uses live view or the video mode that the sensor can get hot and shut down

I have successfully shot over 1440 shots every three seconds using the intervalometer on the camera