Solar or HVAC Career? (I have to choose for tech school training starting in a month)

The OP didnt ask about being an electrician, so I didnt give an opinion on electrical.

Since I am in New England, electricians need licenses in all the surrounding states with fairly steep apprenticeship requirements for being a journeyman and ultimately a master. Most electrical firms know that and take advantage of apprentices. I know several folks who went through that game and starved for a few years until they got enough hours to go journeyman. HVAC is not a licensed trade in many states so it is a lot faster progression to a living wage Code requires a disconnect within site of the equipment so the HVAC techs can work back to the disconnect. Maine, NH and VT tend to be non union shops and the little union work that gets done are usually folks from Mass that can work in other states through comity rules. Mass on the other hand had for many years a very corrupt electrical trade, the only way someone got in the program was through a family connection or bribing someone to get in the program. They also had their hands in the licensing boards, I know someone with 10,000 hours that was perfectly legit in three states that was not legit as the hours in Mass had to be submitted on a union developed form. Folks with documentation other than the Mass form would in theory have to go to every employer they ever worked for and have the employer re-certifiy the hours.

IMHO based on my area, the HVAC trade seems to be better way to get up to good living wage faster than going through the electrical apprenticeship. Maine at least will waive some hours for folks who went throgh a community college program but Mass of course will not accept it. I knew a Master in Maine who had to work as an apprentice in Mass due to all the licensing BS.