Having Enough Power on a Boat

How do you make sure you have enough power on a boat to meet all your needs (and wants)? Dave and I both believe that living aboard a boat shouldn’t be a case of “don’t do that, it uses electricity!”

Neither one of us wants to be the amp ogre, always saying what we can or can’t do. We don’t want to feel limited, either. This is where we live, after all.

Our philosophy, first on Que Tal and then aboard Barefoot Gal, was to set the boat up so that while we didn’t live lavishly, we didn’t grumble about not having power for something important to either one of us.

So how do we do it? It’s basically four steps:

• decide your power priorities,
• reduce power needs where feasible,
• have different modes of charging, and
• maintain your batteries.

Choose Your Priorities

First, we decide our priorities. What do we care about having enough power for, and what are we willing to live without? “No amp-ogre” doesn’t mean we can have everything. It does mean that we jointly decide what’s important to us and then set things up so we can have those things.

• We want enough light to see by. No head amps for walking around inside the boat, cooking, or reading.
• We want light in the cockpit: low light for just sitting out, brighter light for dinner, and brighter still for projects that extend into the evening.
• We want to use our laptop and tablet whenever we want, not for a limited time per day. If we need to print something, we want to be able to do so.
• We want to be able to play music (using an MP3 player to the stereo system) and run fans.
• Recharge cordless tools.
• Refrigeration. Watermaker.

I think that the fact that we decide jointly what we want is what makes us feel that there’s no amp-ogre. We respect what we each want and try to ensure that we can both have what’s important to us.

For example, Dave doesn’t use a computer nearly as much as I do, but he’s willing to create a system that meets my needs. And while I may occasionally enjoy popcorn, I wouldn’t necessarily plan to have a popper on board . . . but it’s one of Dave’s favorite snacks.

We both agree that we don’t have to watch movies on the boat or have an electric coffee maker, and we don’t include them in our power budget.

Conserve Power

Second, we reduce the power required as much as is feasible for the things we do want. There are three main things we’ve done:

• We look for low-draw options wherever we can. Replacing incandescent light bulbs with LEDs has been huge. But “wherever we can” also means that when a low draw alternative just isn’t satisfactory, we don’t use it. Case in point: I tried using a tablet as my primary computer because it took a lot less power than a laptop. The small screen, small file storage, and limited USB connectivity drove me nuts when I was trying to write articles or Google information for a project. I found it not worth the amp savings, and I returned to the laptop.
• We used solar lights for much of our “outdoor” lighting. Many of the solar yard lights aren’t really bright enough for our purposes, and we’ve learned to opt for the higher quality lights that are now being made (yeah, we’ve tried the cheaper alternatives). A Solar Kandle Rail Light lights the steps where we land the dinghy. It also gives just the right amount of light for sitting in the cockpit. We use Luci lights (Amazon) for a dinghy light and a bright cockpit light.
• We turn lights and other things off when not in use. We believe in using what we want, but also don’t want to waste power. Most of our electronics stop drawing power when fully charged, but not all do. I unplug our MP3 player and the little device that makes it play via the radio when not in use — both are older and draw power whenever plugged in. Inverters are also turned off when not in use.
• Barefoot Gal had a well-insulated 12-volt refrigerator. It was on the small side, and we did what we could to help it run efficiently.

Have Different Charging Options

Third, we had ample charging from multiple sources. We monitored our power generation and consumption so that we knew our exact battery status at any time. We had a large solar panel with an efficient charge regulator (read more about our solar power here), a Honda generator, and a 75-amp shore charger (if you have a generator, you need to have a reasonably large shore charger to take advantage of the power produced). And of course, the alternator on the engine.

Some cruisers are now also using fuel cell technology on board.

Maintain Your Batteries

Finally, we took care of our batteries. We started with lead-acid golf cart batteries — and our battery monitor ensures that we never discharge them too deeply. They were in a fairly inaccessible location for checking and adding water, so we took a day and added a battery watering system. It allowed us to take about 2 minutes every two weeks, and the fluid level never drops to damaging levels. Well-maintained batteries hold their charge better, enabling us to get more power out of them.

There are new developments in batteries. When you need to replace yours, check to see what option works best for you. We replaced our lead-acid batteries with lithium. They required less maintenance, were lighter, charged more quickly, and could handle a heavier load. Every

The combination of using as many low-draw options as are reasonable and having plenty of charging capability means that we can power the things we want to pretty much as much as we want to. No, we can’t have every electrical luxury, but that’s our choice. And there are no amp-ogres!

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