Abstract: A hybrid spa has a power adapter connected to a 120 V outlet, a battery connected to the power adapter, and a plurality of spa components connected to the power adapter and the battery. The plurality of components includes a jet pump, a circulation pump, a main heater, and a controller. The battery powers at least some of the plurality of spa components and the power adapter powers the rest. The hybrid spa can further include a secondary heater connected to the battery and a power outlet. The secondary heater can assist the main heater when water needs to be heated by more than 5° F.

Abstract: Described herein is an improved spa system including an operating mode that results in efficient and/or reduced electrical energy consumption while ensuring the use temperature is achieved no matter the time and/or date at which the user desires to enjoy the spa. The operating mode described herein may obtain information indicating a time at which a user may like to enjoy the spa, precisely determine a time it may take to heat water in the spa from an ambient temperature to the use temperature, and cause the spa pump and/or heater to begin the process of heating the water to the use temperature at least the determined time prior to the time at which the user may begin enjoying the spa. A spa may not achieve peak efficiency without a spa operating mode that calculates the estimated time to heat a spa from an ambient temperature to the use temperature.

Abstract: Modular spa covers for insulating spa units are described herein. The modular spa covers can include a plurality of panels and a plurality of support structures. The plurality of support structures can be attached to at least one of the pluralities of panels to attached two or more of the plurality of panels to each other. The plurality of support structures can include at least one E-shaped support structure, at least one T-shaped support structure, and/or at least one H-shaped support structure. When attached to the plurality of panels, at least a portion of each of the plurality of support structures can be embedded within the plurality of panels. The plurality of panels and the plurality of support structures can be packaged inside a spa unit during transportation.