Clean & Green - Creating an all electric garbage collecting boat
Towards a zero-emission garbage cleaning boat
We’ve written before about how important it is to clean up plastic pollution in the ocean as well as the war on plastic more generally, but of course these are just part of a much bigger effort to deal with the climate emergency.
We are extremely proud of the work that our pollution control vessels are doing around the world, but we have long been aware that the emissions from the engines on our boats, whilst minuscule in themselves, are contributing to the problem.
In this post, we look at the issues of zero-emission propulsion in the marine environment, and more specifically at the difficulties of using an electric drive on a garbage collecting boat given the need for range and durability.
Why are electric boats important?
Just as other forms of transport are being forced by regulation, fuel costs and public pressure to reduce their carbon emissions, the maritime industry have been looking for ways to operate more sustainably, and that naturally leads boat builders towards electric propulsion.
We have been determined to reduce the overall environmental impact of our garbage collecting boat, to make sure that we aren’t causing different types of pollution whilst we clean up plastic waste! Until the last couple of years though, our options for reducing carbon emissions during collection have been restricted by the limitations in electric propulsion systems available for boats.
Electric Boat facts

The first electric boat was developed in 1839 in St Petersburg, Russia, and carried 14 passengers at 3 miles per hour

The MS Tûranor PlanetSolar is the world’s largest solar powered boat, and was the first electric boat to circumnavigate the earth

The electric shipping market could be worth more than £15bn by 2027
Advantages of Electric Boats

Reduced or zero carbon emissions

Avoid potential pollution from fuel spills

Reduced maintenance requirements - no oil change, impeller change, diesel filter change etc.

No engine noise

Reduced vibration

Reduced fire hazard
History of electric boats

There were a couple of notable exceptions, including where boats were to be used in environmentally sensitive areas such as the Konigsee Lake in Germany, where non-electric boats were banned, and in the military where electric motors remained in use, particularly in submarines.
The critical development over the last few years in electric propulsion, for other uses as well as marine, has been rapid and continued improvement in battery technology – in particular improvements to cost, weight, durability, recharge times and capacity. This has meant that electric motors have become suitable for a whole range of marine uses where previously considerations of range, weight or cost made them impractical.
What Are Water Witch Doing?
Our first electric drive version of the Versi-Cat debris collection craft, built back in 2011 to keep the canals in Amsterdam clean, required a lot of design modifications to accommodate the system. The 8.0m x 2.5m boat ran on two 2 3.5kW pod motors. Li-ion batteries were not readily available and were extremely expensive at the time, so to achieve 6 hours of continuous operation we required a bank of 16 x 330 Ah AGM batteries with a combined weight of over 400kg.
Thanks to the huge advancement in battery technology in recent years – in particular improvements to cost, weight, durability, advanced power management, recharge times and capacity has meant that electric propulsion is now a practical, cost effective option.
We can now offer electric drive options which easily provide the range and durability required for our vessels to function effectively. Now waterway maintenance and debris retrieval can be entirely zero-emission.
Following extensive tests were delighted to announce in November 2019 that our whole range of Versi-Cat litter collection craft and pontoon workboats are now available with optional electric propulsion as standard.
The outboard configuration of this system allows Water Witch to offer it as a direct replacement to our standard four stroke engine power option, with a top speed of 7.5 knots and 6-8 hours continuous operation between charge. Performance increases in battery technology, with 70% lower volume and weight than comparable batteries, means that trim and stability is not affected and overall vessel weight is kept low for easy shipping and towing by road.
Here at Water Witch, we hope to play our part by providing fully electric debris collection and trash retrieval boats to Ports, Marinas and Waterways Authorities around the world. Our range of tried and tested workboats have been developed to offer users a versatile, multi-purpose craft that can perform a wide range of duties in addition to efficient aquatic trash and debris removal.
If you need more information about our workboats and innovative solutions for marine debris and waterway cleanup, please contact us.
+44 (0)151 207 4874 | info@waterwitch.com