make Solar power great again

Currently the Solar pannel is only making 150kw, it is unlocked so late and make so little power. It is so useless. need to buff the pannel. Also, COI is the only game I have ever seen that has solar pannel but has no battery system for it. To make solar power useful, it must to combine with a battery system so the power can be stored when the pannel works and consumed when there is not enough solar.

Solar panels are weak IRL, this is reflected in the game (they are costly to build and needs a lot of maintenance). There is certainly some battery installed, otherwise it wouldn't be able to work at night (night is not simulated though).
You can make steam baterries - electric boilers using only surplus power supplying turbines and generators with lowest priority.
Although there certainly could exists some baterry packs for peak power consuption in game.

You say "unlocked so late", when in reality it is an end-game power source. It basically requires end-game Research and Offices to become viable.

An early version should be available to research at the beginning. And more research to upgrade it a couple of times. And Yes to having batteries to help recover when I surges in power usage.