Let's Talk Electric Propulsion Part 4 - Dealing with Range Anxiety
25 01 2012 Posted by Daniel
This is part 4 in the Electric Propulsion mini-series here at Oddasea.com. So far we’ve covered a pretty thorough overview on electric propulsion, a detailed tour of my installation, and a discussion on recharging and power management. Now, let’s talk about the psychological aspects of using such a different technology - we’ll deal with the good, the bad, and the ugly right here.
I’ve said it before, and I’ll say it again: the electric propulsion drivetrain for a boat, especially a sailboat, requires a different mindset than does an internal combustion engine such as a diesel or gasoline engine. This is unavoidable, and as I’ve covered in previous parts of this series, has both its rewards and its challenges. I’ve talked about a number of the rewards already - clean energy, renewable using natural resources like sunlight, wind, and boat motion, quiet and efficient power, reduced space needs, and a dead-simple drivetrain requiring little to no maintenance beyond keeping the batteries happy. Now, let’s dig into some of the challenges.
I prefer to call these topics challenges rather than problems for a very specific reason: they are only problems if you let them be. For instance, in older times, sailors didn’t have the option of ANY kind of internal propulsion. It was sail, row, or, well, hope your anchor held. Rather than, centuries ago, decrying sailboats for lacking this option, they simply chose to develop their sailing skills, learn the limits of what they could and could not do, and were quite happy with that, in fact. To this day, many small boats have no provisions for propulsion other than sail, and even some large boats eschew the idea entirely. Its not unheard of, and thus I don’t consider it a problem. It’s simply another way of looking at a situation.
Range Anxiety: A Case Study
The first, and most noticeable challenge, from the perspective of someone used to having an engine on their boat, is the range of the electric motors and their associated battery banks. I’ve gone into detail on this back in Part 1, so refer there if you want to understand more about why this is. The general factor is that an electric motor will have 1/10th the range of the equivalent diesel, battery weight for fuel weight equal. My boat has an estimated electric-power range of about 15 nm, though I chose a battery bank half the size of the fuel tanks I was replacing. I can easily add more capacity if I so desire.
Now, to the average boater, that’s absolutely unacceptable. They are so accustomed to the idea that if the wind dies, you motor. If you’re in a hurry, you motor. If you want to sail up the ICW against the prevailing wind, you motor. That’s fine for them, but that’s not the only way to look at the situation. Americans, in particular, have got this whole idea of “getting there” fixed in their heads. In that mindset, it’s not about the trip, it’s about “getting there”, and doing it as fast, for any given mode of transportation, as possible. Now, while I understand that bobbing around in 35C weather in the middle of the South Pacific with no wind for a couple days or even a week in a row isn’t the most fun in the world, what do you think sailors without motors and without cold beverages in the fridge did even, oh, just a couple decades ago? Sure, they didn’t thoroughly enjoy the situation, but it wasn’t necessary that they get out of it immediately.
I’m not advocating going sailing for the express purpose of bobbing around in the South Pacific in 35C weather with nary a breeze for a week. I’m simply giving about the worst case scenario I’ve ever heard anybody throw up as a reasonable likelihood for using - nay, demanding - long range power propulsion on a sailboat. I’ll cover a few other scenarios in a minute, but I have a couple answers for this one.
First, slow down. This is not only a pretty worst case scenario, its also largely avoidable and totally bearable. The ITCZ is variable, but there are better and worse places to cross it, times of the year to do it, and ways to go about it. By spending a little more time preparing, learning about the ITCZ, and where it is at various times of the year, plus planning a trip through it at the right time and where it is narrow (and also setting a course nearly as straight across it as possible) you can minimize the time you spend in it and choose, generally speaking, more favorable conditions for yourself while you are in it. Then, just sit back, bob around, read a book or play the guitar, maybe spend some quality time with the person you are sailing with, and generally chill out for a couple days. This Too Shall Pass.
Oh, I didn’t mention that you can squeeze a couple knots on the electric motor and recharge using solar. That’ll get you out of the ITCZ a bit faster, and that’s without a single drop of generator power, which you can always fire up for more juice and overnight motoring. So there are far more options than the “get there fast” crowd like to talk about. But if “get there fast” is the point for you, then why are you on a sailboat anyway? Fly there and charter a sailboat if that’s your thing.
Now that the Grand Worst Case scenario has been discussed, let’s talk about another “dealbreaker” for a lot of the should-own-a-powerboat-instead crowd: the ICW and the GIWW. But first, my honest opinion: why in the hell would you want to take the ICW/GIWW in a SAILBOAT for more than a short inland passage to get somewhere specific between offshore runs? It’s absolutely a horrid proposition (this coming from a guy who spent nearly 2 weeks on it in a sailboat, mind). The ICW/GIWW was NOT meant to be sailed. It was not designed for sailboats (actually it wasn’t really designed for recreational craft at all), and while SOME sailboats can actually sail it just fine (shoal draft, small boats with low tacking penalty and/or self-tacking rigs come to mind) the majority of our boats in many cases are hardly able to do a 180 degree turn in the middle of the ICW in many parts. And if you’re taking a sailboat in a place specifically designed for a powerboat, you’re on a fool’s errand in my not-so-humble opinion. As far as rivers go, for centuries sailboats have sailed rivers, waiting for the right wind and occasionally being towed along as necessary. Engines have never been necessary for the right boat in those circumstances.
So, there are a couple solutions to this situation as well. The first is obviously not to take a sailboat where that boat is not designed to be. However, if one insists upon firmly shoving a square peg into a round hole as it were, then accept the compromise that comes with that and run a genset in a series-hybrid propulsion manner for the duration of the trip. Of course a compromise is often achievable as well, with offshore runs tempered by inland access if the weather gets feisty. This would be a likely - and entirely reasonable - scenario for the electric motor, as the run to get in the lee of an island often requires only a few miles of motoring in and out, and overnight a wind generator can recharge a good portion the main bank. This allows a useful range heading inshore and, with a good blow, a nearly full charge not even 12 hours later. Those of you less averse to burning fossil fuels can recharge even faster or from even deeper discharge with a genset.
The principle trick remains to think ahead, anticipate the weather, tides, and other factors, be circumspect of your craft and your limitations and to stay within those margins. Over time not only will you be a better sailor but you will also develop a much more healthy philosophy of using your boat as it was designed and not trying to make a perfectly good sailboat into a terrible powerboat1. By following this philosophy, range anxiety will effectively be eliminated. People have been doing it for centuries.
Auxiliary Services
The other major difference in a boat not equipped with an internal combustion engine is that it must differently handle services commonly assigned to the engine. Engine-mounted watermakers, refrigeration, and other large power consumers are not an option. There is less of an option to fire up the engine and recharge the batteries in the middle of a storm. With a small portable genset a certain amount of adverse weather can be handled but nothing particularly serious. The answer, again, is almost more philosophical than physical: preparation. By thinking ahead, reducing the energy consumption of a vessel through conscious elimination of inefficiencies, conversion to manual processes, or other simple reductions in system load, the runtime draw on a main battery bank is greatly reduced. In addition, alternative energy sources such as wind and solar generation are a must. And last, but not least, remember that the electric motor is itself a charging source when the boat speed is in excess of about 5 knots by propeller regeneration. This comes in handy when the wind pipes up. But perhaps most importantly is just to have a very solid electrical system, keep a close watch on your charge state, and treat your batteries with respect. Preparation is the greater part of prevention.
I should note that I personally subscribe to the philosophy that most services people are accustomed to are not, in fact, the conveniences that they pretend to be. I have come to prefer foot-pumped water for its reliability and lower inclination to drain my water tankage in the event of a system leak, for instance. As a result, pressure water does not exist on my boat. Not only am I quite content with the idea, but my guests adjust very quickly and often remark how much they like the arrangement.
Another philosophy I subscribe to is that any electrical device I have aboard my boat I am prepared and able to do without for any length of time include an entire voyage, if necessary or if I so choose. As a result, my electrical system, while convenient, handy, and often quite useful, is not a necessity, with the current exception of my running lights for which I have not been able to find a quality oil-lamp replacement for at any sort of reasonable price.
Final Thoughts
The most dangerous thing on a sailboat is a calendar. ~ Anonymous, oft requoted
Its really true that modern sailing philosophy has so far removed itself from safe, sane, and even enjoyable traditions of sailing as to divorce a great portion of the pleasure from the process and replace it with a great deal of fictitious ideals which are only occasionally borne out by experience. The tragedy is that those ideals replace what are, in my mind, much greater pleasures which are actually borne out by experience quite often. These nearly forgotten pleasures are many. Among them lie confidence in one’s abilities through hard work and self-education. Also included, a true sense of freedom borne out of reliance on skill and creativity versus tools and external systems. But above all, a childish sense of exploration and curiosity, created by the boundless travel afforded by a sailboat, furthered by the lack of need for much beyond some simple and easily obtained materials and bodily sustenance in the form of food and good humor, and ultimately rewarded in the journey itself, a passage of endless serendipity and treasured experiences appreciated through challenge and the clever application of skill to naturally afforded resources such as the wind and water and heightened by the closeness of nature, the lack of abstractions and insulations, and the direct relationship between action and result.
Personally, I find that, in both the advantages and the challenges of the electric motor as compared to the diesel engine, I have taken a great step towards these pleasures and away from the contrivances of industry and commercialized society. I have become more self-reliant and challenged myself to be more engaged with my voyage. I have gained fewer distractions and realized a greater reliance upon and harmony with nature rather than against her, and I have not given up a level of mechanical assistance which is there when necessary and does provide both a greatly appreciated aid and a further degree of peace of mind. As a result, I consider this decision one of the greatest modifications anybody can make to a larger sailboat.
If you are interested in going electric on your boat, I am glad to discuss general questions as well as the topic as a whole. Specific questions to your installation will be best directed to your vendor. And if you need a vendor, I can highly recommend Scott at Electric Yacht, whose technical assistance and product I can personally vouch for.
Thanks for reading this mini-series on Electric Propulsion. Normal blog content will resume forthwith!
Footnotes:
1. Not that powerboats are terrible. Sailboats, however, are near-universally terrible powerboats.
_________ /) _________
Categories : Ship EquipmentI’ve said it before, and I’ll say it again: the electric propulsion drivetrain for a boat, especially a sailboat, requires a different mindset than does an internal combustion engine such as a diesel or gasoline engine. This is unavoidable, and as I’ve covered in previous parts of this series, has both its rewards and its challenges. I’ve talked about a number of the rewards already - clean energy, renewable using natural resources like sunlight, wind, and boat motion, quiet and efficient power, reduced space needs, and a dead-simple drivetrain requiring little to no maintenance beyond keeping the batteries happy. Now, let’s dig into some of the challenges.
I prefer to call these topics challenges rather than problems for a very specific reason: they are only problems if you let them be. For instance, in older times, sailors didn’t have the option of ANY kind of internal propulsion. It was sail, row, or, well, hope your anchor held. Rather than, centuries ago, decrying sailboats for lacking this option, they simply chose to develop their sailing skills, learn the limits of what they could and could not do, and were quite happy with that, in fact. To this day, many small boats have no provisions for propulsion other than sail, and even some large boats eschew the idea entirely. Its not unheard of, and thus I don’t consider it a problem. It’s simply another way of looking at a situation.
Range Anxiety: A Case Study
The first, and most noticeable challenge, from the perspective of someone used to having an engine on their boat, is the range of the electric motors and their associated battery banks. I’ve gone into detail on this back in Part 1, so refer there if you want to understand more about why this is. The general factor is that an electric motor will have 1/10th the range of the equivalent diesel, battery weight for fuel weight equal. My boat has an estimated electric-power range of about 15 nm, though I chose a battery bank half the size of the fuel tanks I was replacing. I can easily add more capacity if I so desire.
Now, to the average boater, that’s absolutely unacceptable. They are so accustomed to the idea that if the wind dies, you motor. If you’re in a hurry, you motor. If you want to sail up the ICW against the prevailing wind, you motor. That’s fine for them, but that’s not the only way to look at the situation. Americans, in particular, have got this whole idea of “getting there” fixed in their heads. In that mindset, it’s not about the trip, it’s about “getting there”, and doing it as fast, for any given mode of transportation, as possible. Now, while I understand that bobbing around in 35C weather in the middle of the South Pacific with no wind for a couple days or even a week in a row isn’t the most fun in the world, what do you think sailors without motors and without cold beverages in the fridge did even, oh, just a couple decades ago? Sure, they didn’t thoroughly enjoy the situation, but it wasn’t necessary that they get out of it immediately.
I’m not advocating going sailing for the express purpose of bobbing around in the South Pacific in 35C weather with nary a breeze for a week. I’m simply giving about the worst case scenario I’ve ever heard anybody throw up as a reasonable likelihood for using - nay, demanding - long range power propulsion on a sailboat. I’ll cover a few other scenarios in a minute, but I have a couple answers for this one.
First, slow down. This is not only a pretty worst case scenario, its also largely avoidable and totally bearable. The ITCZ is variable, but there are better and worse places to cross it, times of the year to do it, and ways to go about it. By spending a little more time preparing, learning about the ITCZ, and where it is at various times of the year, plus planning a trip through it at the right time and where it is narrow (and also setting a course nearly as straight across it as possible) you can minimize the time you spend in it and choose, generally speaking, more favorable conditions for yourself while you are in it. Then, just sit back, bob around, read a book or play the guitar, maybe spend some quality time with the person you are sailing with, and generally chill out for a couple days. This Too Shall Pass.
Oh, I didn’t mention that you can squeeze a couple knots on the electric motor and recharge using solar. That’ll get you out of the ITCZ a bit faster, and that’s without a single drop of generator power, which you can always fire up for more juice and overnight motoring. So there are far more options than the “get there fast” crowd like to talk about. But if “get there fast” is the point for you, then why are you on a sailboat anyway? Fly there and charter a sailboat if that’s your thing.
Now that the Grand Worst Case scenario has been discussed, let’s talk about another “dealbreaker” for a lot of the should-own-a-powerboat-instead crowd: the ICW and the GIWW. But first, my honest opinion: why in the hell would you want to take the ICW/GIWW in a SAILBOAT for more than a short inland passage to get somewhere specific between offshore runs? It’s absolutely a horrid proposition (this coming from a guy who spent nearly 2 weeks on it in a sailboat, mind). The ICW/GIWW was NOT meant to be sailed. It was not designed for sailboats (actually it wasn’t really designed for recreational craft at all), and while SOME sailboats can actually sail it just fine (shoal draft, small boats with low tacking penalty and/or self-tacking rigs come to mind) the majority of our boats in many cases are hardly able to do a 180 degree turn in the middle of the ICW in many parts. And if you’re taking a sailboat in a place specifically designed for a powerboat, you’re on a fool’s errand in my not-so-humble opinion. As far as rivers go, for centuries sailboats have sailed rivers, waiting for the right wind and occasionally being towed along as necessary. Engines have never been necessary for the right boat in those circumstances.
So, there are a couple solutions to this situation as well. The first is obviously not to take a sailboat where that boat is not designed to be. However, if one insists upon firmly shoving a square peg into a round hole as it were, then accept the compromise that comes with that and run a genset in a series-hybrid propulsion manner for the duration of the trip. Of course a compromise is often achievable as well, with offshore runs tempered by inland access if the weather gets feisty. This would be a likely - and entirely reasonable - scenario for the electric motor, as the run to get in the lee of an island often requires only a few miles of motoring in and out, and overnight a wind generator can recharge a good portion the main bank. This allows a useful range heading inshore and, with a good blow, a nearly full charge not even 12 hours later. Those of you less averse to burning fossil fuels can recharge even faster or from even deeper discharge with a genset.
The principle trick remains to think ahead, anticipate the weather, tides, and other factors, be circumspect of your craft and your limitations and to stay within those margins. Over time not only will you be a better sailor but you will also develop a much more healthy philosophy of using your boat as it was designed and not trying to make a perfectly good sailboat into a terrible powerboat1. By following this philosophy, range anxiety will effectively be eliminated. People have been doing it for centuries.
Auxiliary Services
The other major difference in a boat not equipped with an internal combustion engine is that it must differently handle services commonly assigned to the engine. Engine-mounted watermakers, refrigeration, and other large power consumers are not an option. There is less of an option to fire up the engine and recharge the batteries in the middle of a storm. With a small portable genset a certain amount of adverse weather can be handled but nothing particularly serious. The answer, again, is almost more philosophical than physical: preparation. By thinking ahead, reducing the energy consumption of a vessel through conscious elimination of inefficiencies, conversion to manual processes, or other simple reductions in system load, the runtime draw on a main battery bank is greatly reduced. In addition, alternative energy sources such as wind and solar generation are a must. And last, but not least, remember that the electric motor is itself a charging source when the boat speed is in excess of about 5 knots by propeller regeneration. This comes in handy when the wind pipes up. But perhaps most importantly is just to have a very solid electrical system, keep a close watch on your charge state, and treat your batteries with respect. Preparation is the greater part of prevention.
I should note that I personally subscribe to the philosophy that most services people are accustomed to are not, in fact, the conveniences that they pretend to be. I have come to prefer foot-pumped water for its reliability and lower inclination to drain my water tankage in the event of a system leak, for instance. As a result, pressure water does not exist on my boat. Not only am I quite content with the idea, but my guests adjust very quickly and often remark how much they like the arrangement.
Another philosophy I subscribe to is that any electrical device I have aboard my boat I am prepared and able to do without for any length of time include an entire voyage, if necessary or if I so choose. As a result, my electrical system, while convenient, handy, and often quite useful, is not a necessity, with the current exception of my running lights for which I have not been able to find a quality oil-lamp replacement for at any sort of reasonable price.
Final Thoughts
The most dangerous thing on a sailboat is a calendar. ~ Anonymous, oft requoted
Its really true that modern sailing philosophy has so far removed itself from safe, sane, and even enjoyable traditions of sailing as to divorce a great portion of the pleasure from the process and replace it with a great deal of fictitious ideals which are only occasionally borne out by experience. The tragedy is that those ideals replace what are, in my mind, much greater pleasures which are actually borne out by experience quite often. These nearly forgotten pleasures are many. Among them lie confidence in one’s abilities through hard work and self-education. Also included, a true sense of freedom borne out of reliance on skill and creativity versus tools and external systems. But above all, a childish sense of exploration and curiosity, created by the boundless travel afforded by a sailboat, furthered by the lack of need for much beyond some simple and easily obtained materials and bodily sustenance in the form of food and good humor, and ultimately rewarded in the journey itself, a passage of endless serendipity and treasured experiences appreciated through challenge and the clever application of skill to naturally afforded resources such as the wind and water and heightened by the closeness of nature, the lack of abstractions and insulations, and the direct relationship between action and result.
Personally, I find that, in both the advantages and the challenges of the electric motor as compared to the diesel engine, I have taken a great step towards these pleasures and away from the contrivances of industry and commercialized society. I have become more self-reliant and challenged myself to be more engaged with my voyage. I have gained fewer distractions and realized a greater reliance upon and harmony with nature rather than against her, and I have not given up a level of mechanical assistance which is there when necessary and does provide both a greatly appreciated aid and a further degree of peace of mind. As a result, I consider this decision one of the greatest modifications anybody can make to a larger sailboat.
If you are interested in going electric on your boat, I am glad to discuss general questions as well as the topic as a whole. Specific questions to your installation will be best directed to your vendor. And if you need a vendor, I can highly recommend Scott at Electric Yacht, whose technical assistance and product I can personally vouch for.
Thanks for reading this mini-series on Electric Propulsion. Normal blog content will resume forthwith!
Footnotes:
1. Not that powerboats are terrible. Sailboats, however, are near-universally terrible powerboats.
_________ /) _________
