Winner: Generators
Battery systems are generally more expensive then generator systems. Small, portable battery powered systems may be cheaper if you are only looking to power a few small devices. Batteries are expensive and in order to ensure your investment lasts you actually need to buy battery capacity that will remain unused. Batteries degrade rapidly when they are significantly drained so ideally you want your battery bank to remain atleast 50% charged at all times. Battery systems also require various additional components like chargers and invertors which add to the cost. Read more.
Winner: Batteriess
Generators require regular maintenance to ensure they remain in optimal running condition. The heart of a generator is the motor and it has service intervals just like a car. Changing oil, spark plugs, air filters and oil filters is part of owning and operating a generator. Modern batteries, especially those used in backup systems are generally maintenance free.
Depends
Batteries store energy while generators can only burn fuel to create energy when required. The energy stored in batteries can come from a variety of sources including the grid, solar and wind. If you choose a solar or wind based system that means that you will save money by virtue of using free energy. If you are financing your backup system the increased cost of a battery based system will result in higher financing costs. Both batteries and generators will experience wear and tear.
Winner: Batteries
Generators are noisy. If you are looking to use the generator in your home and noise is a concern then batteries may be the better option
