Boat Engines: Annual Co2 Emissions And Their Impact

Boats release harmful substances into the environment, including carbon dioxide, nitrogen oxide, particulate matter, carbon monoxide, and non-methane volatile organic compounds (NMVOCs). While boating may not feel as environmentally damaging as driving a car, it can still be harmful to the health and persistence of global ecosystems.

In 2019, ships and boats in the US produced 40.4 million metric tons of carbon dioxide. However, this figure includes emissions from commercial shipping fleets, so the exact amount produced by boat engines is unclear.

Boat engines contribute to the increasing carbon dioxide concentrations in the atmosphere, which has a detrimental impact on ocean ecosystems.

How to calculate a boat's carbon emissions

A boat's carbon footprint is the emission of CO2 primarily from burning the fuel in its engine(s) and generator. No two boats are the same, and each will have a different footprint. The size and type of the engine(s), their age, the fuel type, your average cruising speed, the fuel efficiency, and the number of hours you use your boat all contribute.

To calculate your boat's carbon emissions, you can follow these steps:

• Determine the average number of gallons your engine(s) use per hour.
• Multiply this number by the total number of hours you use your engine(s) during a specific period, such as a season or a year.
• The result will give you the total number of gallons of fuel burned during that period.
• To find the carbon emissions in pounds or tons of CO2, you can use an online boat carbon calculator or refer to scientific publications and international statistics for emission factors.

By keeping track of your fuel usage and calculating your boat's carbon emissions, you can gain a better understanding of your boat's impact on the environment and explore ways to reduce your carbon footprint.

How to reduce a boat's carbon emissions

Reduce Fuel Consumption

The key to lowering a boat's carbon footprint is to decrease its fuel consumption. This will not only benefit the environment but also save money.

Utilise Carbon Offsets

Purchasing carbon offsets is one way to help address the imbalance that our daily lives have on the environment. A carbon offset is a reduction in carbon dioxide emissions made to compensate for emissions made elsewhere.

Opt for Climate Neutrality

Going "carbon neutral" is not enough. To be truly climate neutral, you must remove the equivalent of all your boat's greenhouse gases at the same rate that the vessel is releasing them.

Choose the Right Boat

No two boats are the same, and each will have a different carbon footprint. The size and type of engine, the fuel type, and the number of hours the boat is used all contribute to its emissions.

Be Mindful of Speed

How fast you drive your boat can influence how much you impact the underwater ecosystems, not only because of GHG emissions but also from noise and collision risk with aquatic wildlife.

Eco-Friendly Maintenance

Even boat maintenance activities like antifouling can harm the environment due to the toxic chemicals used. Opt for eco-friendly maintenance practices to reduce your carbon footprint.

Choose Sustainable Fuels

Sustainable liquid marine fuels, such as renewable drop-in fuels, are expected to be the most suitable source of energy to decarbonize recreational boats by 2035, reducing emissions by up to 90% without compromising performance.

Hybrid Technology

Hybrid boats that use both electric and internal combustion engines offer the potential for reducing carbon emissions, especially for boats used for longer periods and greater distances.

Electric Propulsion

Electric propulsion is part of the strategy to decarbonize, but it is not suitable for all types of recreational craft and use cases. Electric-only propulsion may have a higher GHG contribution from raw materials and manufacturing than conventional propulsion systems.

Hydrogen

Hydrogen is an emerging technology with the potential to reduce carbon emissions from boats, provided its production process is optimized. Hydrogen, when produced via electrolysis with zero fossil fuel electricity, can reduce carbon emissions for certain craft categories.

The dangers of carbon monoxide on boats

Carbon monoxide is an odorless, colourless, and tasteless gas that is produced when a carbon-based fuel, such as gasoline, propane, charcoal, or oil, burns. It is a component of exhaust gases and is produced by engines, gas generators, cooking ranges, and water heaters.

Carbon monoxide is dangerous because it enters your bloodstream through the lungs, blocking the oxygen your body needs. Exposure to high concentrations of carbon monoxide or prolonged exposure to low concentrations can be deadly.

Symptoms of carbon monoxide poisoning are often confused with seasickness, intoxication, or motion sickness. They include:

• Irritated eyes
• Headache
• Nausea
• Weakness
• Dizziness
• Confusion
• Fainting

Carbon monoxide poisoning can also result in death.

Carbon monoxide is particularly dangerous on boats because it can collect on or near your boat. It is present in the exhaust produced by gasoline engines and is released through the exhaust ports of vessels that are idling or underway. It can also accumulate in closed-off, poorly ventilated areas of a boat when its engine is running.

To protect yourself and your family from carbon monoxide poisoning on a boat, you should:

• Use a marine-grade carbon monoxide detector
• Ensure proper ventilation by opening foredeck hatches and windows in the cabin
• Inspect the exhaust system regularly for leaks, discolouration, water leaks, carbon build-up, or stains
• Seal gaps around the engine room and exhaust system doors, hatches, and access panels
• Stay away from the transom (where carbon monoxide collects) while the vessel is idling or underway
• Avoid other idling vessels, which are a prominent source of high concentrations of carbon monoxide

How to treat carbon monoxide poisoning on boats

Carbon monoxide (CO) poisoning is a serious and deadly issue for boaters. It is a colourless, odourless, and tasteless gas that is undetectable by human senses. It is produced when carbon-based fuels, such as gasoline, propane, charcoal, or oil, are burned.

Prevention and Detection

Firstly, prevention and detection are key. Install and regularly maintain a marine-grade CO detector, similar to a smoke alarm, which will alert you to the presence of CO. Ensure your boat is well-ventilated by opening foredeck hatches and windows, especially when the engine is running. Inspect your exhaust system regularly for leaks, discolouration, water leaks, carbon build-up, or stains. Seal gaps around the engine room and exhaust system doors, hatches, and access panels.

Recognise Symptoms

Be aware of the symptoms of CO poisoning, which include nausea, dizziness, confusion, headache, and fainting. These symptoms are often mistaken for seasickness, alcohol intoxication, or exhaustion. If anyone on the boat starts experiencing these symptoms, move them to the front of the vessel to get fresh air and put a life vest on them.

Emergency Response

If you suspect CO poisoning, act quickly. Shut off all potential sources of carbon monoxide and open all doors, windows, and awnings. Call an emergency medical hotline and inform them of your suspicions. If the affected person is not breathing, begin CPR and continue until they recover consciousness or emergency services arrive.

Medical Treatment

Follow up with a medical facility if needed. Oxygen therapy treatment may be required, depending on the severity of exposure. The sooner you can get medical attention, the better the chances of recovery.

Remember, carbon monoxide poisoning can be prevented and treated with the right knowledge and equipment. By taking the necessary steps, you can help keep yourself, your passengers, and fellow boaters safe.

How to prevent carbon monoxide poisoning on boats

Carbon monoxide (CO) poisoning is one of the top five causes of death among boaters. It is also one of the most preventable. A buildup of this colourless and odourless gas beneath the stern deck or near the swim deck can kill someone in seconds. Here are some ways to prevent carbon monoxide poisoning on boats:

Get Moving

Avoid prolonged periods of idling and travelling at slow speeds as this can cause carbon monoxide to build up in your cabin, bridge, cockpit, aft deck and open areas.

Balance the Load

Do not operate the boat at a high bow angle. Overloading or improperly loading the boat puts you and your passengers at risk of back drafting, which can lead to CO build-up in your cabin, cockpit and bridge.

Breathe Easy

Blocked ventilation louvers and exhaust outlets can cause CO to accumulate in your cabin and cockpit. Be sure to check and maintain these items, as well as your CO detector, regularly.

Spread Out

Avoid water skiing, wakeboarding, tubing and surfing within 20 feet of the boat while it's moving. And don't dock, anchor or raft within 20 feet of other boats that have engines or generators running. This tip can also help you avoid propeller injuries.

Move Forward

Do not sit or swim near or under the rear deck or platform while the engine or generator is on. Boating safety experts recommend avoiding this area for at least 15 minutes after the engine is shut off.

Other Tips

• Allow fresh air to circulate throughout the boat at all times, even during bad weather.
• Know where your engine and generator exhaust outlets are located and keep everyone away from these areas as they can contain the highest concentration of carbon monoxide.
• Ventilate immediately if exhaust fumes are detected on the boat.
• Install and maintain CO detectors inside your boat. Replace detectors as recommended by the manufacturer.

Frequently asked questions