The get-up-and-go a sunny day gives you? (5,6)
I believe the answer is:
solar energy
'a sunny day gives you?' is the definition.
I can't judge whether this defines the answer.
'the get-up-and-go' is the wordplay.
'the get-up-and' becomes 'solar' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'go' becomes 'energy' (I've seen this before).
'solar'+'energy'='SOLAR ENERGY'
Can you help me to learn more?
(Other definitions for solar energy that I've seen before include "Power derived from the sun" , "Sun's radiant power" , "Green power source" , "Radiation from the sun" .)