why would you want to put the power back into the grid?
if you are getting paid a higher rate for the electricity you put back i can understand it.. in which case you could run a power cord to your neighbors house and pull power out of the grid and then push it back up the grid through your system.. i'm sure someone has thought of this before but i've never seen a headline for someone getting caught lol.
anyhow assuming you can get a system approved and built, you can add additional capacity later.
here is a product that might work for you, but it may not meet the code to be installed.
https://windandsolar.com/skymax-wind-grid-tie-inverter/anyhow i would recommend just buy a 500 watt grid tie inverter and power it from a battery bank. use the wind turbine to charge the batteries. once you get such a system working mess with it later. the power loss from charging and discharging the batteries will be fairly minor depending on the frequency of charge and discharge. you may be able to find creative ways to limit the outflow of the grid tie inverter to match the wind turbine production, without turning it on and off and thus save the life of the batteries and minimize their degradation.
vertical axis wind turbines are usually less efficient, larger than horizontal wind turbines.
however depending on many other details you may find them easier to construct and work on.
if you're located near any large towns, call up hvac companies and ask them for their broken inverter fan motors. they are typically 1/3rd to 1 hp motors, at 1250 rpm, 10 or 12 poles, 56 C frame, and they have a 4" long 1/2" diameter shaft sticking out of them. most common failure is the magnets debonding (glue them back on). inverters failing (don't need them anyways) and the bearings failing (they use 6202 bearings)
they are relatively low sticking torque and can easily be re-wired for delta which means at 1200 rpm they will only produce about 100 vac.
Depending on your windspeed profile available and how big you want to build some turbines, you might use a belt drive to spin the generators, or just direct drive them.