How Much Power Does a Seakeeper Use?

Running out of power for your Seakeeper while out in choppy seas would be the worst! Once you’ve experienced Seakeeper stabilization, you’ll never want to roll at the mercy of the waves again. So, ensuring you have enough power to keep the stabilization going for your entire outing is crucial.

Figuring out your power requirements starts with determining what size Seakeeper your boat will need and what type of power it runs on. The Seakeeper 1-4 runs exclusively on DC power, and the Seakeeper 4.5 and larger are AC-powered. You can find the power consumption of specific models on their respective product pages. Sizing a generator for AC-powered Seakeepers is more straightforward, so this FAQ focuses on sizing a battery bank for DC-powered Seakeepers. 

Spool-Up & Operating Power Requirements

The most power that your Seakeeper will draw is during spool-up, and for our largest DC-powered model, that takes 60 minutes. Check out the spool-up and operating power requirements in the table below. We recommend spooling up on shore power and switching to battery power when leaving the dock.

Amperage draw at 12VDC

Seakeeper Battery Bank or House Battery Bank

Next, is the decision to dedicate a battery bank to your Seakeeper or to integrate the Seakeeper into your house battery bank. A Seakeeper battery bank keeps the Seakeeper isolated from any other power draws on the boat. The alternative is to add the Seakeeper to your house bank, with the Seakeeper and other house loads sharing one common source. 

There’s no right or wrong answer when deciding how to configure your battery bank. If you choose to do one integrated house bank, it’s crucial to think about everything on your boat that uses power and how much power it draws – everything from lights, pumps, instruments, communication equipment, refrigeration, air conditioning, and sanitation, to your stereo or simply charging phones. You want to ensure your battery bank is sufficient to power all of it, plus the varying loads of a Seakeeper. 

Battery Technology, Group Size & Capacity

Four battery chemistries are common in the marine market, and the battery technology you select will affect how efficiently it powers the Seakeeper.

Flooded Lead Acid – The most common and least expensive type of battery used today. These tend to be the least efficient, require more maintenance, and only have a life cycle of a couple of hundred cycles. Because of their limited life cycle, Seakeeper doesn’t recommend this kind of battery.

Gel Cell and Absorbed Glass Mat (AGM) – Both of these sealed batteries are more efficient than flooded batteries, less prone to leakage, and have a life cycle of around 500 cycles, but they are more costly.

Lithium Ion – These batteries are gaining popularity for their power density, but safely operating them requires a battery management system to control their charge and discharge. Their life cycle is around 2,000 cycles before performance falls. 

Another consideration when selecting a battery is its group size, which simply refers to its physical dimensions. If you’re sizing batteries for an existing battery tray, you’ll want to pay attention to the battery group size to ensure it fits. 

The last important aspect of your battery is Amp Hour (Ah) capacity. A larger battery group size typically results in a higher capacity, but that isn’t always the case. Each DC-powered Seakeeper model has a minimum Ah capacity recommendation that you’ll want to ensure you meet. For the Seakeeper 1, the minimum capacity is 150 Ah, for the Seakeeper 2 and Seakeeper 3, the minimum capacity is 200 Ah, and for the Seakeeper 4, the minimum capacity is 220 Ah.

Each type of battery has benefits and drawbacks, but in general, Seakeeper recommends deep-cycle Gell Cell or AGM batteries that meet the Seakeeper model’s minimum capacity recommendations. 

Power Draw & Safety Shut Down

Seakeeper continually monitors battery voltage, looking for the optimal 12VDC from the battery bank. But battery voltage gradually decreases as it discharges. If Seakeeper detects a voltage as low as 11.1VDC, it activates the DC Low Voltage Shutdown, slowing the Seakeeper down before your battery bank is completely drained. At this point, you would need to turn your engines back on or connect to shore power to recharge your batteries. 

Without additional power, Seakeeper keeps slowing itself down and drawing less energy until the battery voltage dips below 11.0VDC, triggering the DC Input Voltage Low alarm (Code 111). This alarm forces a Seakeeper shutdown and lets you know, “Hey, we’re out of juice here! It’s time to recharge or conserve what’s left!” Thanks to Code 111, the Seakeeper will shut down before any other system, leaving you with enough battery power for essentials like navigation and other critical equipment.

Desired Seakeeper Runtime

How long do you want to run your Seakeeper without recharging or running the engines? Our DC-Battery Runtime Calculator can help you calculate what size battery bank you need to achieve that! The runtime calculator can determine battery requirements for a desired runtime or what runtime you can expect from a specific battery configuration. All you need to do is add a few details about your Seakeeper and battery configuration. 

Keep these minimum capacities in mind when building your battery bank!

Battery Configuration in Our Sportsman 262 Demo Boat

Our Sportsman 262 demo boat is stabilized with a Seakeeper 1. We use this boat for fishing tournaments, demos, and the occasional boat show, so we don’t always have access to shore power for spool-up. On a typical day, we run all our electronics on board, including the stereo. We opted to integrate the Seakeeper 1 into our house battery bank and made sure we had enough power to support the spool-up and operating power requirements. So, our battery bank consists of 2 deep-cycle flooded lead acid, Group 31 batteries with a battery capacity of 105 Ah each. With this setup, we get about 2 hours and 45 minutes of runtime before we need to crank the engines back up to recharge.

Have more questions about the Seakeeper battery needs for your boat? Read our full Battery Sizing Recommendations bulletin, or reach out to a Seakeeper Dealer to chat about the specifics!