solar panels on a boat

Solar panels for boats

Owning a boat can be an expensive proposition; not only do you have to pay an upfront cost to purchase it, but you’ll also have to spend money on maintenance and fuel charges. If you’re looking for a reliable and cost-effective way to power your boat, solar panels may be the answer.

How do solar panels work on boats?

Solar energy systems on boats work similarly to other portable, off-grid systems. There are four important components to a marine solar panel system:

  1. Solar panels
  2. Charge controller
  3. Inverter
  4. Battery

When sunlight hits a boat’s solar panels, it generates an electrical current. A battery stores this current so that you can use it to support your boat’s electricity needs. Most marine solar panel systems also require charge controllers to prevent the batteries from receiving more voltage than they’re capable of handling – without charge controllers, you risk overcharging and damaging your battery.

Depending on the electrical setup of your boat and the types of appliances you need to energize, you may also need an inverter to convert direct current (DC) electricity into alternating current (AC) electricity. Some boat electronics use DC and as such do not require an inverter with a solar panel setup. However, if you use some everyday household appliances on your boat (i.e.TVs, microwaves, or hairdryers), they likely run on AC electricity and you’ll need an inverter.

You can buy all of these components separately, but there are also solar panel kits available that include some or all of the necessary parts. Additionally, some marine solar panel kits also include the wires, cables, and mounting equipment necessary to get your boat’s solar panel system completely up and running.

Best solar panel kits for boats

There are a number of options available when it comes to buying a solar kit for your boat. Below are a few products that are tailored to off-grid marine solar power systems.

Boat solar panel options

ProductCostPanel wattage (W)Included equipment
Renogy flexible solar panel$200100 WNone
WindyNation solar panel$160100 WCharge controller, connectors, mounting brackets
Renogy solar panel$175160 WNone
Newpowa solar panel$100100 WNone

If your solar panel kit does not include an inverter or charge controller, you’ll need to buy those components separately. Battery storage products occasionally have built-in inverters and/or charge controllers.

Should you install solar panels on your boat?

There are numerous benefits to powering your boat with solar energy. One of the most attractive benefits of marine solar power systems is the monetary savings. You’ll need to invest money upfront to purchase solar equipment; however, once it’s up and running, you’ll be generating free electricity for your boat. Alternatives to electrifying your boat, like gasoline-powered generators, require purchasing fuel on an ongoing basis. Switching to solar power can cut down on these purchases while protecting you against rising fuel costs.  

Another benefit of marine solar panel systems is the quietness of operation. For those going out on the open water to experience nature, running a generator can be a noisy disturbance. By powering your boat with solar, you can enjoy peace and quiet without losing power.

Furthermore, you can also safely generate electricity and charge your battery with solar power while you’re away from your boat. This isn’t feasible with generators – running a generator requires manual operation and monitoring. With solar panels, you can produce usable electricity during the day and then use it for weekend boating adventures.

However, there can be obstacles to installing solar on a boat, perhaps the largest of which is available space. Ideally, your solar panels can be installed in an area with uninterrupted sunshine. Depending on the type of boat you have, this space may be easy or difficult to come by. While you likely get a lot of sun out on the water, the space it may be too small or have too many obstacles that make fitting the number of solar panels necessary to generate all of your electricity needs difficult.

When you’re looking for spots to install a marine solar panel system, consider your boat’s deck or canvas. Keep in mind that the positioning of your solar panels will also impact the type of equipment you should purchase – you may be able to use traditional monocrystalline and polycrystalline solar panels if you’re installing on a fixed, rigid section of your boat. However, if your only open space available isn’t suitable for fixed mounting, then installing lower-efficiency flexible solar panels may be a better option. Some flexible solar options have an adhesive backing so you won’t need to worry about the constraints of traditional mounting and racking materials.

How many solar panels do you need for your boat?

Unsurprisingly, a yacht has very different power requirements than a sailboat. The number of solar panels you’ll need for your boat not only depends on the type and size of your boat, but also the quality of the equipment you choose, how many sun-hours the boat sees, and the amount of electricity you require. Some boats can get by with one 100-watt solar panel (or even smaller), while others require a multi-panel setup.

The first step in figuring out how many solar panels you need is to calculate your electricity load. Below are some common appliances you may be using on your boat, and what they draw for power.

How many solar panels do you need for common appliances?

AppliancePower consumption (W)Daily hours of use Daily power consumption (Wh)
Lightbulb60 W6360 Wh
TV200 W4800 Wh
Microwave800 W.180 Wh
Mini-fridge200 W244,800 Wh
Fan400 W2800 Wh
Blige pump40 W140 Wh
GPS display50 W3150 Wh

The last column of the above table is the amount of energy you’ll consume in watt-hours running each appliance for the number of hours identified in column three. One 100-watt solar panel that receives direct sunlight for 5 hours will produce approximately 500 Wh of electricity (5 hours x 100 W = 500 Wh). Not taking into account conversion losses, that’s enough electricity to power a mini-fridge for 24 hours, or power a boat’s GPS display for 10 hours. Running all of the appliances above for everyday use will require multiple 100-watt solar panels or fewer higher wattage panels.

Install solar to save on electricity bills

You can certainly save money by installing a marine solar panel system, but you’ll save even more by installing solar on your home or business. If you’re interested in evaluating your solar options, check out the EnergySage Solar Marketplace. You can receive up to seven custom solar quotes from local installers to compare side-by-side. Looking to start out with a quick estimate of solar costs and savings on your property? Try our Solar Calculator.

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About Kerry Thoubboron

Kerry is an expert in all things solar! She's worked in the industry for more than 6 years, starting her career as an Energy Advisor dedicated to helping customers compare their options and make well-informed solar decisions. She graduated from Boston University with a degree in Environmental Analysis and Policy. Outside of work, you can find Kerry snowboarding, watching The Office, or having passionate debates about which New England state is best (spoiler: it's Vermont).

12 thoughts on “Solar panels for boats

  1. Mark

    Your solar charge controller should recognize the input from the alternator as the battery being fully charged. So it should stop charging the batteries allowing the alternator to do it job

  2. Robert Pike

    I have set up a 100 watt panel in the backyard and ran the cable into my man cave in the basement where I set up the controller and battery . All is working perfectly , just waiting for the lake to thaw out before installing it on my boat in the spring . My question is , if I leave it connected when I start the engine and go boating , Will the engine’s alternator harm the solar charging system having read that one should never have more than one system running at the same time .

    1. Sis

      Overall its a great article and very informative on the benefits of solar and nuances of using solar in a boat. Thanks very much for this excellent piece.

      One concern though-“One 100-watt solar panel that receives direct sunlight for 5 hours will produce approximately 500 Wh of electricity (5 hours x 100 W = 500 Wh). Not taking into account conversion losses, that’s enough electricity to power a mini-fridge for 24 hours..”

      How is 500Wh enough to power the 200W fridge which consumes 4,800 Wh in 24 hours as you listed? (As a side note, the fridge compressor will typically run for 8-12 hours during 24-hour run period. Which means it will consume 1600-2400Wh per day)

  3. Brendan John O'Reilly

    I am purchasing a 10m x 5m houseboat and I wish to have solar panels, controller, batteries and inverter. My appliances will be washing machine, standard size fridge, split air con unit, 12 volt lights, toaster, kettle, microwave and tv. Are you able tò give me a rough idea on what sort of controller, inverter how many and what size batteries and solar panels I will need. Thanks heaps in advance Brendan

  4. mljet national park from dubrovnik

    Solar panel for boats is yet another revolutionary and environmental friendly step taken by many boat manufacturing and travel agency. They save energy provide us fuel from direct solar sources which helps in maintaining the electrical control system and communication systems as well.

  5. alex

    Hello there! Alex here, how much power do I need to run permanently a refrigerator and a frizer 24/7 and the rest of a 42 sailboat ,this includes cabin lights stereo and one or two notebooks ? I thought 600 Wh will be in off being very conservative ,please give me an approximate,the boat is in Florida,.Thanks Alex.

  6. Thomas Westgren

    I love how you mentioned that having solar panels on your boat is great because it allows things to work really quietly. Having the right boat parts would also be really important though, to keep those panels working well. If my wife and I were ever to get a boat we’d have to be sure to hire someone with good parts to ensure that we keep things working well.

  7. Sarah Packer

    My husband and I have thought about buying a boat for a while, so we wondered if we should rent first and what we should look for in a boat. I didn’t know a lot of marine solar panels need a charge controller, so you don’t overwhelm your panels with too much energy. I’ll have to keep that in mind and I’ll find a boat rental company that we can use to figure out if we really want a boat!

  8. Jaclyn Pereir

    Trying to get more information on the type of solar set up that is needed to run electric engines through recharging lithium battery set up. Want to make my boat into a Tesla; lol. Less discharge/waste, no running out of gas and truly off grid without limiting my trips

    1. Julie

      Jaclyn, were you successful in finding that info? I’m looking to do the same. Using the greenline hybrid as my model of inspiration. I would like to convert a small houseboat.


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