Lightning is a sudden electrostatic discharge that occurs typically during a thunderstorm. This discharge occurs between regions of a cloud(called intra-cloud lightning or IC), between two clouds (CC lightning), or between a cloud and the ground (CG lightning).
The charged regions in the atmosphere temporarily equalize themselves through this discharge referred to as a flash. A lightning flash can also be a strike if it involves an object on the ground. It creates light in the form of black body radiation from the very hot plasma created by the electron flow, and sound in the form of thunder. It may be seen and not heard when it occurs at a distance too great for the sound to carry as far as the light from the strike or flash.
Lightning is a flow of electricity, and as such cannot be stored. But it may eventually be possible to store the huge amount of electric charge that comes down during lightning discharges. No one as yet has perfected the technology for that.
To capture each and every lightning strike (land strikes only) we would most likely have to put extremely tall towers (think Eiffel tower) around a mile apart in a grid formation covering the entire globe. Yes, the entire globe as many strikes occurs over the oceans and seas. That is one tower for each of the almost 200,000,000 square miles of the earth’s surface.
Although in comparison, one hour of sunlight has the same amount of energy that we use in a year! We have much more power available from the sun and we only need our rooftops to accumulate all we need. Especially with the advances and improvements being made with solar panel efficiency.