First Question, What size train?
Second question. what proportion of the time do you intend the train to be running?Using those panels, the answer will probably have to be very occasionally. Solar panels seem to under-deliver for me, but that may be because I live in the Northwest of England where it rains a lot.Back to first question, do you have a multimeter, so you can check how many mA the train's motor draws?
If we crunch a few numbers, we can easily get an idea of how long the train can be run via the solar panels.12V solar panels at 25mA = 300 mW of power.12V motors drawing 2A = 24 watts of power (or 24000 mW).At 100% efficiency (unrealistic, but just to get some ballpark numbers), for every minute the train runs, the solar panels will need more than 80 minutes to recharge. If we factor in the inefficiencies of the system, you're looking at increasing that time by upwards of 50%.