One way charge on hydro/solar system

Good day guys, I need some advice or help please. We have a 5 kw solar system and a5kw hydro electric system for our electricity needs. The solar system is fine but my issue is with the hydro one. It consists of a massive water wheel turning an ac generator. From the geni the output goes 2ways. 1to the ac grid and the 2nd to a bridge wich makes it dc and passes through a charge controller to a battery bank(48vdc). There is a 10kw inverter linked to the bank. Here is my problem: The ac grid gets preference when a load is applied wich puts strain on the ac genetator and inturn on the drive frome the wheel. Is it possible to take the full ac output and rectify it , feed it to the bank and let the inverter take the load from there like with the solar system?I basically want to have the water wheel and its geni to only charge the bank and block the load from straining the geni. So I will then have the geni on the wheel pushing a charge to the bank but some kind of electronic device preventing a massive draw from the generator unit like an electronic one way valve if I can call it that. Any ideas please?