Please define survival.  Power-outage with recharge after power restoration, or self-sufficient backup power supply which recharges based on wind conditions?
Either way, it would depend on how many watts they're pulling.
I can offer some inverter-chargers which will act as UPS units, they're often found in RV setups.  However, I would prefer the wind generator setup based on ease of use and connection without the requirement of grid-power to recharge batteries.