Second, the charger itself has built-in inefficiencies, especially if it has a large transformer. These generators are capable of putting nearly their full power into a battery bank, since no additional charger is required. The disadvantage of these is that they cannot be used independently of an inverter-based system as household 120 VAC backup. If you have access to any combination of solar, hydro, and wind, you have the advantage of access to complimentary systems. Often when one isn't able to produce, the other is at its prime.
Backup power can come either from a generator or from the utility grid.
Most renewable energy users have the goal of not using backup power. Articles are in Adobe Acrobat 4 format and available for Mac, Windows, MS-DOS, and Unix computer operating systems. Acrobat versions earlier than 4.0 may not work with our PDF files. Link to the Adobe site to obtain a free copy of Acrobat reader. Back to systems page .