Traditional grid-tie systems are systems in which solar panels are
placed as a roof mount, a ground mount, or elsewhere, and then the light
and energy from the sun is gathered through the panels and is then
transferred to an inverter, which converts the power into usable energy.
With the basic grid-tie system, there is a connection with the utility
company, however, there are no battery backup solar systems, and so if there
were to be a power outage, your reliance on connectivity to the grid
means you would be completely without power even with having the solar
panels installed.
And so, in order to not be stuck without power and to be able to be
self-sustaining in the case of an emergency, your best option is to have
a grid-tie system with battery back-up which gives you the option to
both use the utility company when needed and build credit with them, and
be self-sustaining in case of an emergency.