I agree solar panels can be great - I also have them at a great price with return around 6 years. However, in terms of priorities, I would not want a car on PCP, and I would maximise pension first. It is to be fair a no regrets move if you can get a deal with low payback period - a real low payback period i.e one calculated by you not a seller.
The needle mover for OP here will be assumptions about future income - a child can change the assumption of both working very quickly - and the equation will not be as simple as child minder cost is lower than income.