Charging an electric boat is easier than you think
Columns with 230V-contacts is quite common in harbors and piers today. These are being used to charge electronic equipment on board boats, but is it also enough to charge an electric boat?
Volt, watt, Ampere, kW and kWh, what can be charged where, for how long, how fast and what kind of plug? We receive many questions regarding charging an electric boat and what might be needed to own an electric boat. So we want to give you the answers to the last questions you might have before you order one of our boat models or choose to go for an electric motor in your boat.
Power from the harbor
At most pier facilities around the world there are columns for 230 volts (V), such as the one in the picture above. These have existed for a long time, and have been used to charge electronic equipment on board the boats on the piers. Here, the standard color of the socket is blue, but if you see a socket that is red, it is a 400V socket that is suitable for more professional use.
How much energy you get from an electrical outlet is determined by the current (amperes /A) with which the equipment loads the socket. It is common to have fuses of 10, 13 or 16A on the pier system. The fuse will limit the maximum amount of energy you can extract. This means that if you try to use equipment that needs 13A but the plug you connect to is secured with 10A, the fuse will short circuit. To avoid this, all our boats will be able to charge at 10A. Also our GW 630X with up to 3.3kW charging - but then the charger must be adjusted down. This happens automatically if you connect a TYPE 2 charging station - or you can adjust this on board the boat.
We have developed our boats for overnight charging, in the same way most people charge electric cars. This is because boats are on the same pier all season, and you always return to the same berth after the boat trip. And when charging for several hours, it is not necessary to have a high charging speed and lots of power, especially when the battery pack on board is smaller than most battery packs in electric cars. Thus, fast charging is not a need for normal use of an electric recreational boat.
“10kWh battery pack in a GW 601 gives you more than enough power for a whole day at sea, even if the electric car on land can have 80kWh.”
The charger is not on land
In the GW 601 and in most electrification packages we deliver, a 1kW on-board charger is included and the GW 630X comes with a 3.3kW charger. It is a myth that the "charger" is the one you connect the boat or car to, that is just a plug. The actual charger is installed in the car or on board the boat, and that is what determines the speed for charging. So when you plug a GW 601 into a power socket on the dock, the charger on board will set the speed to 1kW and keep that speed until the battery is full.
With a 10kWh battery pack in a GW 601, it will after 10 hours of charging at 1kW power reach a full charge. The amount of energy in a battery is thus both defined by how much energy it can deliver "all the time" measured in kilowatts, and the time you can extract that energy in hours. Therefore, a battery is defined with kWh, where the h stands for hour.
Charging of a GW 601 is done with the same type of cable as most sailboats, and the speed is not more than 1kW. It will take 10 hours to charge from 0-100%.
Also read: Five good reasons to buy an electric boat!
Does it draw too much power from the pier?
We have become accustomed to electric cars needing large amounts of electricity, all the time. This is because electric cars are used every day, all year round. In recent years, electric cars have been given larger battery packs that provide more range and the ability to keep high speeds longer. Fortunately, a car and a boat are quite different. By car, you want to reach a destination quickly, at constant high speeds. If you are out in a leisure boat, time is something you have more than enough of. It's a vacation, you relax, and the speed is low. Therefore, we can say with certainty that a 10kWh battery pack in a GW 601 gives you more than enough power for a whole day at sea, even if the electric car on land can have 80kWh.
“By keeping the speed low when driving an electric boat, you also keep the power consumption at your pier system low.”
Unlike an electric car, a boat is not used every day. On average, a boat trip with a leisure boat in Norway lasts three hours. With, for example, a GW 601 or a GW 630X, you will typically have around 50-70% battery left when you return to the pier after such a trip, depending on speed. If you then charge up to 100% with a GW 601, you have only drawn around 5kWh from the pier system. To put this in perspective, you must drive the electric boat for three hours a full 40 times (or 120 hours in total) to reach the same amount of electricity as an average monthly consumption in a 40sqm apartment in Norway! So the amount of electricity you draw from a pier with an electric boat from Green Waves is not large.
As with electric cars, you will also have a higher consumption of power with an electric boat at higher speeds. If you go from 5 to 7 knots with a GW 601, the consumption of electricity will triple and the driving time will be greatly reduced. The increase is thus exponential. So by keeping the speed low when driving an electric boat, you also keep the power consumption at your pier low.
One question many ask themselves when charging an electric boat is whether the charging cable can continue to be connected to the boat, even if the batteries have become full. With electric boats from Green Waves, that will not be an issue. When the batteries become full, the charger stops automatically and no more power reaches the batteries. The cable can thus be connected in the boat for a long period of time without damaging the batteries. In addition, it is no problem to charge the batteries to 100% every time, as our batteries are based on iron-phosphate chemistry (LFP). This means that they can withstand being fully charged without compromising capacity.
Three things to consider before buying an electric boat
We have received a number of inquiries about what to think about before buying an electric boat from Green Waves. Therefore, we end this article with three simple recommendations you can look at before placing an order on one of our models, or go for an electric motor in your existing boat:
Check where the power plug is located in relation to your mooring. If it is far away, charging can be tricky. You can of course get a longer charging cable, but then it must be safely placed and not become a trip hazard for other boat owners. Also, remember that the charging cable should not come into contact with water.
Find out how much power you get out of your socket. Is it 16A or 230V everything is ok, but is it only 10A for example, you will get a slightly reduced speed if you charge the GW 630X. This does not apply to GW 601.
If you rent a berth at a pier, we can recommend that you inform the owner of the pier that you are considering an electric boat. If he or she is unsure of what this will mean for the power consumption, you can refer to this article. Do you happen to have your own column at your berth, it may also be an idea to install an electricity meter if the owner of the pier facility is unsure of how large the load will be.
We hope this article has made you a little wiser on charging an electric boat! If you have more questions, feel free to check out our answers to frequently asked questions here, or click here to call us!