Green Boating From a Practical Perspective

For real impacts, we need to address habits both on and off the water.


Before diving into the topic of responsible boating, we’re required to say something about global warming and carbon. Primordial carbon was sequestered by several mechanisms. Fossil fuels seem the most obvious, but in fact that represents only a tiny portion of the total.

Most found its way into carbonates sediments, including limestone and sandstone. Plants, of course, are a big sink, but even more is captured within the soil as organic material, both as compost and peat-like material and as microorganisms. And don’t underestimate that last category; bacteria, and fungi out-mass all other life on earth.

The ocean tells a similar tale. Preventing pH drop (a consequence of carbon emissions and acid rain) will allow more carbonates to precipitate into shellfish, coral, and most importantly in terms of tons, diatoms ( PMC7464044/). These microscopic creatures are major factors in carbonate precipitation in the oceans.

Better husbanding of soil and water quality around the world can pull carbon from the air. As it has been for centuries, clean drinking water is an especially valuable resource to sailors (see PS July 2015, Keeping Water Cool and Fresh”).

As humans, our responsibilities are pretty straightforward: be kind to the soil and be kind to the ocean. And while we buy time for the planet, maybe we’ll find a way for carbon to be sequestered as carbonates.


For most of us, boating is a form of recreation. We don’t need it to survive— as we do air, water, and food—but life would be pretty bleak without it. As such, sailing is only green if it produces a smaller footprint than likely alternative activities that fulfill our impulse to play. How does sailing compare to hiking? Cycling? Kayaking? Surfing? Given what it takes to build and maintain a boat, the fuel needed to get to the boat, and the fuel burned underway, sailing needs to clear a pretty high bar to match the carbon footprint of these activities, But maybe, with effort, we can get close.

If you live aboard, your footprint is small to start with. Good on you. For rest of us, owning a house and several cars means most of our impact is not boat related. We have a larger footprint and no amount of recycling or sustainable choices will make an elephant into a mouse. Ostensibly, this article is about clean boating, but for most of us the rest of our life is by far the larger contribution, so we need to consider the whole picture if we want to feel good about our boating habit.


Don’t buy what you don’t need. Recycling water bottles is good, but not buying them is better. Using a green cleaner is good, but rinsing with water and squinting at a few stains is better. Don’t replace lines just because they are stained and don’t use strong chemicals to remove stains that don’t matter.

The best recycling is reuse. Use it up. Maintain it. It does not need to be new. Then donate or resell things that are usable. But don’t use donation as feelgood trash disposal. Freecycle bins at marinas are a great outlet for old ropes and left-over materials, such as hose and fabric. They go fast.

Search thrift shops: cheap work clothes or used Carharts are more comfortable, last longer and cost less than Tyvex coveralls. I haven’t bought new Goretex or fleece in 40 years; I find like-new cast-offs that either went out of style or someone gained weight.

Stop “wish-cycling.” If you cannot confirm that the recycling collector wants a certain item, it is not recyclable, and including it increases recycling cost.

For example, my curbside pick-up recycler only recycles plastic water bottles, LDPE milk and food containers, clean paper and cardboard, aluminum cans, and steel cans. The rest, including all other plastics, glass, and paper with coatings or attached plastic, goes in the trash. Including a prohibited item increases the recycler’s sorting and disposal cost, and potentially reducing the value of the sorted product. It doesn’t matter that polypropylene or styrene are recyclable in principle or that the item has a recycle code on it. If it’s not on the recycler’s list, they don’t have an outlet for it and it is not worth the their time to identify all of the plastic types and separate them.

Bottom line: If you cannot confirm practical access to recycling outlets, no matter what the label says, it is not actually recyclable.


We’ve found that many manufacturer’s “eco-friendly” claims made without proof are just nonsense. When buying perlite for this project I noticed that some bags were labeled “organic.” This makes no sense at all.

Perlite is a mineral product made from volcanic glass and thus is not an organic material. It contains no organic additives. The claim is nothing but words on a label. We’ve seen cleaners labeled as biodegradeable that were based on inorganic salts. If the company has a strong reputation, or if the ingredient list makes sense to you, OK, but keep your BS filters on and never believe that a green label means the footprint is dramatically less.

Fortunately, the US EPA has reviewed many of the claims and has published a list of certifications they recommend ( If the product label is not on the EPA list, I disregard it. If it is on the list, I recognize that it is probably a little bit better, but probably not a whole lot better than alternatives, and that using less is best.


Most recycling is down cycling. Plastic water bottles become clothing, which is used only once. Recycled clothing takes 25-35 percent more dye.

Recycled PET makes 32 percent less CO2 and takes 59 percent less energy than virgin PET and 20-30 percent is also discarded from the waste stream, making the overall process less than 50 percent efficient under the best of conditions. For comparison, used oil recycling, on the other hand, is 85-90 percent efficient, after correcting for water and contaminants.

Fiber ropes are not recycled in large scale because the UV has damaged the polymer too much and because identifying polymer type is too difficult (blends are impossible to recycle at this time). Paper becomes lower quality paper, as the fibers become shorter. Fortunately, this degradation is not very important for many recycled products, because enough virgin material is still needed to fill the open loop, and this dilutes the degraded properties.

Green Boating From a Practical Perspective
A simple homemade pot skirt helps conserve cooking fuel. Such efforts become more valuable in distant ports, when cooking fuel is hard to come by (see PS June 2016 Pot Skirt: DIY Cooking in the Wind).


Many of the synthetic products we use replaced organic ones that could be grown or sustainably produced. The synthetics lasted longer and performed better, but as more manufacturers see sustainable profits in sustainable products, some of those original organic products, improved by new technologies, are making a comeback.

However, some of these sustainable products have much shorter useful lives, requiring more energy during the manufacturing process which can offset any green gains.

For example, is nylon rope better than hemp, even though it is not recyclable or renewable? It is stronger, lasts many times longer in a damp environment, and is safer. Perhaps the overall impact on the environment is still less, since one rope replaces 10.

A bamboo bicycle frame makes a statement, but given the vast number of perfectly good, used metal frames on the planet, this doesn’t add up. I still ride my 1979 college bike to the store, something a bamboo frame would not have endured without careful treatment (I treated it badly) and faithful (and environmentally harmful) refinishing. In the end, steel is very recyclable, but a bamboo frame, with attached fittings and epoxy, is just noncompostable trash.

Is fiberglass better than wood because with typical maintenance it will last longer? (Yes, a wooden boat can last 100 years, but we also know that 15-25 years is more typical, versus 40- 60 years for fiberglass). And either way, you still have the disposal problem, since the main problem is the labor to dismantle the boat, not the disposal of the fiberglass. Either way, in places like the U.S. where fiberglass recycling is in its infancy, it’s going in the landfill.

Balsa and plywood are often touted as sustainable, but I wonder if there is a correlation between balsa cores and a boat’s early demise? This is certainly true of plywood cores. Foam cores can’t be sustainably produced, but if the boat lasts long enough, this impact is mitigated. Sustainable is not always better than durable.

Renewable was the old buzz word. Firewood is renewable, but burned in a typical fireplace it pollutes the air more than other heating methods. It is not sustainable, in terms of hazardous air pollutants or global warming. Solar is better, but making panels has impact.

Bottom line: Switching to “sustainable” products can help minimize our impact, but a simple and often more effective way to reduce our impact is to reduce consumption. Sometimes, as in the case of heating, this means system design changes like improved insulation. In other cases, it is simply resisting the urge to buy.


Boating closer to home pays off in saved time and energy. Since I started boating, I estimate I have used about as much fuel commuting to the boat as underway. Carpool if the commute is long. Combine boatwork trips with sailing days, knocking out a few small things, taking measurements, or spending the night aboard to finish the project in the morning. Multi-day visits to the boat—sailing or not—pack a lot more activity into the time and mileage. If you fly to a charter destination, stay longer and go less often.

Green Boating From a Practical Perspective
Old rope is good for boat projects—baggy wrinkles, door mats, etc. — or for uses like fender pendants and tarp tie-downs. Don’t expect it to support high loads (PS December 2007, “Used Three-strand Rope Faces the Ultimate Endurance Test”).

Boat sharing. Perhaps one of the easiest ways to reduce your impact is through boat-sharing. If pride in ownership means a lot to you, by all means own your own boat. I have, three times. But I’ve also enjoyed my current partnership. This reduces expenses, work, and my personal footprint.

Fuel management. Avoid spills (“Taking the spill out of Fill-ups,” November 2016). Upgrade your fuel cans. The early CARB cans were terrible, but the new generation reduces emissions and eliminates spills.

If your dinghy or boat runs on gasoline, reduce evaporation by upgrading to low permeation lines and a low permeation portable tank. Fuel lines should be replaced every 10 years or so, anyway. Keep the portable or integral tank vent closed when not actually running—this reduces vapor emissions, water absorption, and consequent carburetor corrosion, clogging, and phase separation. If you have an installed gasoline tank, add a vent filter (see PS January 2013, “EPA Mandate Sparks Fuel-vent Filter Test”).

Slow down when motoring. By staying well below hull speed, fuel consumption can be halved and noise is reduced. About 60-70 percent of hull speed usually results in the best efficiency in a properly matched hull, engine, and prop. (See PS September 2016, “Determining a Fuel Efficient RPM”). Some newer common rail diesels come with fuel consumption gauges.

When cruising, allow extra time. If the wind is too light to sail, you can stay an extra day and sail farther on the next leg. Choose a flexible itinerary that allows you to pick weather conducive to sailing rather than motoring.

Sustainable power sources. Instead of generators, use solar and wind power to charge your batteries. LED lighting has made it practical to meet our essential power needs using sustainable sources.

Fridge-free sailing. You can cruise for years without a refrigerator (see PS March 1, 2003 “Helpful Refrigeration- Free Food Ideas for Your Next Sailboat Outing”), or at least improve the efficiency of your existing unit (see PS October 2013, “Fine-tuning Fridge Efficiency.” Good insulation is key. Check out, “Keeping You Cool: Improving Your Icebox.” www.practicalsailor. com/boat-maintenance/keepingyou- cool-improving-your-icebox

Avoid air conditioning. Americans are closely attached to their air conditioning, but as Eric Dean Wilson describes in his new book After Cooling: On Freon, Global Warming, and the Terrible Cost of Comfort (July 2021, Simon and Schuster, $28), this convenience has proven to be a very inefficient way to keep humans cool. Before diving into air-conditioning, explore ways maximize ventilation through the use of hatches and vents (see PS September 2020, “Simple Tips to Improve Ventilation”) .

Electric drives. An emerging technology with limitations on range, electric propulsion still holds promise, especially for marina-based sailors in fresh water environments, which are free of the corrosive effects of saltwater (see PS September 2008, “Electric and Hybrid Propulsion for Sailboats”).

Use few disposables. Allow no paper plates or disposable cups, use glass tupperware instead of freezer bags, and maintain your water system so the tap is fresh (see PS August 2015 “Tap Water That’s Better Than Bottled”). Who has room for the extra trash anyway?

Follow marine sanitation rules. As municipalities continue to struggle with wastewater problems ashore, boaters can set an example by obeying local restrictions. Consider composting or desiccating toilets. They have notable advantages in small boats and in areas where pump-outs are scarce, specifically freshwater lakes (see PS July 2021, “Dissecting the Desiccating Head”)

Green Boating From a Practical Perspective
The acids in waterline stain cleaners have little impact on the water quality, but they are often unnecessary. A scrub-pad is all you need for moderate waterline slime.

Keep your graywater clean. Don’t drain food grease down the sink (save it in a jar). Minimize soap usage. Get clean by swimming, so all you have to do is rinse (see PS November 2011, “The Best Products for Staying Clean on Board”). Avoid 2-stroke engines. They are light and reliable, but the smaller ones pollute way too much. There was a time when biodegradable 2-stroke oils made a splash. Turns out it was just greenwashing and they went away.

Avoid anchoring on sensitive bottoms. Sea grass is vital to sea life and damaged coral does not come back. Pick up a mooring. Go somewhere elsewhere. Search for a patch of clean sand. Minimize scope to reduce scouring the bottom with your chain. Sometimes a very small fender tied about 20 feet from the anchor will lift chain off the bottom to reduce damage to the sea bottom.

Maintain your boat. The best recycling is continued use and maintenance, so don’t be the dreaded “previous owner” that let the boat go. If you’re tired of boat work, that’s your cue to sell the boat to someone with the enthusiasm to keep her up. Buy something smaller (see.

Keep the prop clean. Vibration is bad for the cutless bearing and even slight fouling wastes a lot of fuel. This alone is good reason to have a wet or dry suit, if the climate requires it. For sailors who want to minimize dips in the water, I’ve had good results with the Davis 4400 Scrubbis.


Reducing impact means reassessing maintenance routines. Assuming you can keep bottom drag at bay, minimizing haulouts automatically reduces your footprint.

Bottom paints. Two-year bottom paints are cheaper in the long run, reduce cleaning, and release copper at a slower rate than one-year paints— slow release is how they last two years. If you must use a one-year paint, apply only one coat if possible; this will reduce build up and release less copper.

Do not scrub ablatives. It shortens their life and does not actually keep them clean longer (see PS April 2018, “Bottom Paint Care”). If you must scrub, use the gentlest possible method and scrub before it gets ahead of you, requiring more aggressive methods (no hard growth). Several eco-friendly paints have proven effective, especially in freshwater (see PS May 2018, “Freshwater Bottom Paint Test”).

Less deck washing. Learn to squint. A boat is a tool for adventure, not fine crystal for display as a demonstration of wealth. A water rinse, perhaps with a little spot scrubbing, is most often enough.

Fight interior mildew with leak prevention, ventilation, and borax. We see a lot of good stuff thrown way simply because of black spots from mildew.

Use the least harmful cleaner. Rinse first. Most cleaners work better on pre-wetted stains and they streak less. More soak time is always better than more soap. Gently cleaning teak decks regularly with seawater reduces the need for cleaners. Boat Zoap (Sudbury) is effective, cheap, and has tested very low impact (see PS January 2013, “Best Boat Soaps for Regular Washdowns”). Use very little. Citric acid is good for stainless (see PS July 2020, “Passivating Stainless.”) Keep the bilge squeaky clean; dry is best, if you can.

Use non-flammable solvents (like diesel) for cleaning winches and parts when possible. Alternatively, you can look for low odor or Rule 66 compliant (reference to California regulation) mineral spirits. Not very good for thinning paint, but quite suitable for cleaning. In many cases, such lowerhazard solvents can be recycled along with the used oil (the process recovers diesel as a side cut). Note: we do not recommend water-based mineral spirits replacements. They’re basically useless and not recyclable.

Recycle solvents. They can often be reused after settling for a few weeks. Seal them up in a mason jar and watch what happens.


Living green is a change in mindset. Less is more and everything has consequences, and green labels don’t change that much.

Always pick up litter. Since it costs nothing, this is probably the most efficient way, in dollars per pound, to keep plastics out of the water. Bending over and picking up stuff in the gutter can be good exercise. Don’t wait for the local sanitation workers, or someone else to do the job for you; it will rain before that happens.

Creating a Composting Galley

Most sailors commonly feed their scraps to the fish, reasoning the meat wastes are consumed in short order. However, sensitive areas and freshwater lakes may demand more care.

Grease. You can’t discharge it anywhere and you can’t compost it. Save it for waste disposal ashore.

Composting. Several years ago, related to several PS testing projects, we started composting kitchen waste as a way of creating a very active environment to accelerate the decomposition of TP and wood, and mildewing of fabrics. We stopped at the end of the projects because the kitchen waste bin stunk and dumping it every day, often in foul or cold weather, was a drag. Since then, we’ve learned the right way to do it.

The right bin. Our kitchen now sports a Utopia can. As long as we avoid meat waste, the combination of a carbon filter in the lid and sufficient ventilation controls anaerobic smells (avoid meat waste). At $31 it seemed a little pricey, but we found ours at the thrift store for just a few dollars (reuse is best!). The real upside is that our kitchen trash can no longer stinks and we can wait until it is full to empty it. An easy win, and one that transfers to boating.

On the boat, in the summer, kitchen trash becomes foul in a hurry, and it’s hard to get away from. See also PS “Trash Compactor,” April 2020 for a tip on reducing trash volume by packing it in boxes.

Disposal into a composting or desiccating head is another option (see PS August 2021). In any case, ventilation is essential to controlling odor; a completely sealed bin will quickly turn ripe.

Drew Frye, Practical Sailor’s technical editor, has used his background in chemistry and engineering to help guide Practical Sailor toward some of the most important topics covered during the past 10 years. His in-depth reporting on everything from anchors to safety tethers to fuel additives have netted multiple awards from Boating Writers International. With more than three decades of experience as a refinery engineer and a sailor, he has a knack for discovering money-saving “home-brew” products or “hacks” that make boating affordable for almost anyone. He has conducted dozens of tests for Practical Sailor and published over 200 articles on sailing equipment. His rigorous testing has prompted the improvement and introduction of several marine products that might not exist without his input. His book “Rigging Modern Anchors” has won wide praise for introducing the use of modern materials and novel techniques to solve an array of anchoring challenges.