In embodiments, the energy storage device may comprise a component of a photovoltaic output management system. Advantageously, the energy storage device may optionally store electrical power generated by a photovoltaic system in excess of that consumed by a load otherwise powered by the photovoltaic system, which may occur, for example, during times of peak power production or low demand. In some embodiments, the energy stored by the energy storage devices may be useful for smoothing the output variability of a photovoltaic system over time and may for example, be useful for maintaining a substantially constant or less variable output from the photovoltaic system as energy production changes from moment to moment (e.g. due to a passing cloud). Additionally, the stored energy may optionally be provided to and used by a load connected to the photovoltaic system when the photovoltaic energy production is lower than that required by the load, such as during times of high demand, or during night or on cloudy days. In this way, the energy storage device may enhance the utility of a photovoltaic system by allowing storage of excess energy when generated, use of stored energy when insufficient generation occurs, and maintaining substantially constant output as photovoltaic power is modulated.