Digital Ultrasonic Antifouling - a Green game changer??

by Des Ryan on 10 Jul 2010 The introduction of digital ultrasonic antifouling may have changed the game for this green and simple method of antifouling. While the system was analogue, it was not only expensive, but chewed up much power. Digital is at least 20% lighter on power, and the price has reduced somewhat.

Even with that undeniable fact, yacht owners who have responded to my queries about how they find the system, vary considerably. This is likely to be due to a number of variables:

1. Where they keep the yacht. Cold water does not breed algae or barnacles at nearly the same rate as rich tropical water does.

2. How often they use the boat. The ultrasonic waves do not remove algae or barnacles that are already there. They kill them, but do not remove them, so it requires either movement through the water or an antifoul to effect removal, and movement does not remove barnacles

3. How the system was installed. The position of installation is critical to efficient operation.

The benefits of moving to this technology are considerable, however, say the manufacturers who claim your hull will remain clear of growth constantly, making transits faster at the maximum speed/revs for the boat. The critical items are also kept growth free - impellors, water intakes, rudders and propellers. Even if you don't care about the speed, fuel will be saved all the time you are running your motor, because of less resistance.

The first installation is the expensive one, as you not only have to pay for slipping the boat, but also for the installation of the gear. However, after the first hit, the proponents say the system should pay for itself in both ease of handling, reduced fuel charges and the lack of the necessity to slip the boat every year.

So, if you believe ultrasonic anti-fouling is for you, the argument for using a digital method is pretty much the same as installing solar panels on your roof for electricity supply - more expensive in the beginning, but cheaper in the long run, and Green.

Just how expensive the units are depends, like most other marine gadgets, on the length of your boat. Boats up to 10 metres will cost less than $2000 to install, and a boat up to 20 metres will cost less than $4000 to install. A catamaran, with two hulls and therefore more surface to cover, will probably want the 20 metre version, even for a smaller boat length.

If you're handy, you can probably install the system yourself, and the important factor is the positioning to get the maximum benefit. Do beware, if the system is not installed correctly, it will not operate to the maximum.

They come in both 12-24volt and 120-240volt systems, for connecting in a marina or for staying on a swing mooring. There's a solar charger for swing moorings, unless your already existing system will serve as well.

There are some recommendations:

1. They won't serve you if you have a mud mooring. Only that part of the hull which is in the water would be kept barnacle and algae free.
2. You are highly recommended to start with a clean hull. While the system will kill growth on your boat in a short period of time, it will NOT remove the barnacles, and algae can only be removed by using the boat.
3. The system will only work if it turned on all the time. Talking to those who have not left their systems on all the time, they find that they still have to antifoul the boat, but the system keeps it relatively clean and faster in the water.
4. If you are located in warm tropical waters where growth is fast, you will need more ultrasonic power than if your boat is located in temperate or cold waters.

For more information, go to any one of a number of suppliers for your local area, but here's a site to start with:www.ultrasonic-antifouling.com.

It may not be for you, but it's certainly worth considering. Watch the video, and then check out your local supplier for the prices that will apply to your boat: