Are Your Boat Electrics

Safe & Reliable?

...or do they look like this:

  • Your boat's electrics are a "black box" to you?
  • You are worried that parts of your system might fail?
  • You want to install and maintain a DC system on a boat like a pro?

Sounds familiar?

Nigel Calder
Dr. Jan C. Athenstädt
Michael Herrmann

We are Nigel, Jan & Michael.
We help you understand, extend and redo your boat electrics.

The right way.

I now understand all the electrical systems and how everything works together.

Bob Russell - S/V Spartina

Jan, Nigel & Michael,
I want to let you know how impressed I was with the BoatHowTo course!!
Having purchased a new to me Island Packet 350 this year, I was overwhelmed with all electrical systems on the boat!
Modern cursing boats have become very complex and I was lost!
Having taken your Boat Electrics 101 course I now understand all the electrical systems and how everything works together.
From the very basics, through creating a detailed circuit diagrams of the electrical systems on my boat, my knowledge is years ahead of where I thought it would be at this point.
Thanks for a wonderful, extremely useful (and fun) course that takes a lot of the mystery out of sailboat electrical systems!! 

Boat electrics is not rocket science...
...but it still has to be DONE RIGHT!

Electrical systems on boats have become more and more complex over recent years.

Even moderately equipped boats today rely completely on their electrical system. A loss of power means in most cases an emergency at sea. (Or do you still have a sextant and all nautical almanacs on board?)

Boat electrics are often poorly understood, despite being such a vital part of the operation of a boat.

The good news: It's not that hard!

With a bit of time and a commitment to learning, everybody who mastered basic high-school math and physics will be able to understand the DC system on a boat. All it takes is a reliable and easy to understand source of information.

Clearly expressed and illustrated, the course is full of practical information

Derek Nowek - Falmouth, ME

he Boat Electrics 101 course is a fantastic resource for beginners like myself who know little about electricity and even less about boats electrical systems. Clearly expressed and illustrated, the course is full of practical information presented in a way that makes boat electrical systems understandable. Thank you for putting it together.

You want to understand your system?

The majority of fires that start on boats 
are caused by the electrical system!

Understanding your boat's DC system can significantly improve the safety of your boat!

Unfortunately, many owners have only a vague understanding of their boat's electrical system. Or, even worse: They think they know how to install a system and end up making damaging mistakes...

...and teach others these mistakes in blogs or on YouTube. 

YouTube is full of videos about Boat Electrics

– many  are wrong and some are dangerous!

The internet is a great source of information. And in recent years, many people have shared their experience installing or fixing electrical problems on their boats.

The problem: Many of those people are not professionals!

It's easy to put a professionally looking video on YouTube...

...but it is hard to tell, if this actually is professional advice - or misleading BS.

If you follow bad advice on how to varnish teak and you end up with a mess, in the worst case you lose time and a bit of money.

If you follow bad advice on how to connect batteries and your boat ends up in flames, this is a different story. 

A typical example of bad advice... soldering. Soldering is often praised as a great way of connecting wires. On a boat, it is not. Soldered connections are rigid and tend to break when exposed to the vibrations common on boats.

This is why electrical installation standards from the American Boat and Yacht Council (ABYC) and the European International Organization for Standardization (ISO) both explicitly prohibit soldering as the only means of connection!

You want know how to do it right?

Your brand new boat is properly wired...

...or MAYBE NOT?

When visiting boat shows, Nigel likes to inspect the electrical systems on brand new boats. Unfortunately, this has become quite frustrating: a shockingly high number of production boats come with badly installed electrics – straight from the boatyard.

These batteries were installed on a brand new boat. What's wrong here?

  1. Inadequate support against sliding off the shelf
  2. Parallel connections badly designed - this will lead to premature battery death
  3. Too many cables on the positive battery post
  4. No overcurrent protection devices anywhere near the positive battery pole

This installation might look neat at first glance. But:

It is unprofessional and asking for trouble!

You want to assess your system?

Who or what are ABYC and ISO?

The ABYC E-11 and the ISO 13297 standards cover the principal electrical systems on small craft.

Even though they are legally non-binding, they are based on decades of experience of hundreds of experts in the field. 

So, instead of trying to figure things out for yourself (with potentially disastrous consequences), it is a good idea to follow these standards as closely as possible.

Nigel and Michael have been long-term members of various standards committees of the ABYC and ISO. Everything we teach at BOATHOWTO is compliant with ABYC and ISO standards. 

There is no one who knows the standards better than us.

The American Boat & Yacht Council (ABYC) is a non-profit, member organization that develops voluntary global safety standards for the design, construction, maintenance, and repair of recreational boats. As an independent consensus-based body, the industry experts at the ABYC (including Nigel Calder from BOATHOWTO) work together with the sole purpose of protecting the safety of the boating public.  

The ABYC’s Standards and Technical Information Reports for Small Craft cover all major boat systems. The development and regular review of these standards provide boat building guidelines that correlate directly with a significant reduction in the number of boating accidents over the past six decades.

The International Organization for Standardization (ISO) develops high quality voluntary International Standards. The sub-group of the ISO that addresses small craft (up to 24m/70 feet), is known as Technical Committee (TC)188 (of which Michael Herrmann from BOATHOWTO is a member). This committee has developed a set of standards that are closely aligned with the ABYC standards. 

With respect to boat electrical systems the principal difference between the ABYC and ISO standards lies in the fact that the ABYC standards tend to be more detailed. In order to provide the most detailed information in our lessons, we follow the ABYC standards. Where there are minor disagreements with the ISO (only a handful) we point these out. 

You want your electrics to comply with ISO & ABYC standards?

We know what we are talking about...

...and how to apply this knowledge.

Understand the basics of a safe and troublefree installation. Learn how to plan and design a system. Get practical advice on how to put everything in place.


Understand the basics of electrics in general and boat electrics in particular


Learn how to assess existing systems and how to (re-)design the wiring of your boat


Get your hands dirty with practical advice on how to crimp wires, install batteries and much more

The course has given me the knowledge to make better choices

Tommy Kaine - SV Alboe

Just a note to say how terrific the Boat Electronics 101 course is. It is very comprehensive. It has empowered me to refit my 1976 Westsail 32 original electrical system. Though I am outsourcing some of the work, the course has given me the knowledge to make better choices, do my portion of the project, and have a smart conversation with the contractors. Thanks for all your hard work and keep it up!

Good marine electricians are rare...

...and expensive!

So why not learn how to do it yourself?

Instead of paying hundreds of dollars for a few hours of advice and help from a marine electrician, you can invest in your knowledge - and become more self-reliant!

With our help you can learn how to operate, maintain and extend your boat's electrical system in a professional manner. Better than many people who do this for a living!

Invest in your knowledge and self reliance

Even if you know a good marine electrician: You will still have to deal with problems on your own as soon as you are away from the dock.

Proper preparation is key to good seamanship. 

Stop worrying about potential hidden failures in your system. Empower yourself by uncovering the secrets of your boat's electrical system. Regain control in the complex world of marine electrics.

BOATHOWTO helps you spend a carefree and relaxed time on the water. Boating or sailing the way it's meant to be.

Join us for our ONLINE COURSE on DC Systems:

BOATHOWTO Boat Electrics 101

Safe & Reliable DC Systems

Set up a safe and reliable DC system on your boat that complies with ABYC and ISO standards.

  1. 1
    Fundamentals: Understand the basics of electricity, how common components work and how to connect them.
  2. 2
    Batteries & Charging: How do lead-acid batteries work and how to charge them to double or triple their lifetime?
  3. 3
    System Design: Step-by-Step guide to plan and install a DC-System on your boat.

In 8 modules, you will learn everything from the basics of electricity to designing a whole DC system on your own.

Boat Electrics 101 - Course Contents

59 easy to follow video lessons will turn you from beginner to expert. 

Take a look at the course syllabus:

A quick welcome and introduction of your teachers and a few words on who this course is for and what to expect.

Get an overview on the contents of this course and the underlying standards.

In this lesson we will cover some dangers and necessary safety precautions to keep in mind before working on your system.


Get to know the basics of electricity and learn about Volts, Amps, Ohms and how they relate to each other.

What is electricity?

What is electricity and what happens when a current flows? We take a quick look at the behavior of electrons inside metallic conductors.

Voltage, Current & Resistance

Learn all you need to know about voltage, the equivalent to pressure in electrical systems.

Ohm’s Law

Ohm's law allows you to calculate how resistance affects voltage given a certain current and vice versa.

Power, Energy, Consumption & Capacity

Power the product of voltage and current. With two examples you will learn how to calculate the power draw of an appliance.


A quick recap on everything we have learned so far.

Electrical Components and Circuit diagrams

Get to know the most common components of a boat's electrical system and learn how they can be represented in a circuit diagram.

The Idea Behind a Circuit Diagram

Learn why it is important to be able to read and draw circuit diagrams.

Wires & Conductors

In this lesson you learn the symbols for wires and wire connections.

Circuit Ground

What is ground/earth and how is it represented in circuit diagrams?

Switches, Buttons & Relays

Get to know the basic symbols for switches and buttons and learn how relays and solenoids work.

Resistors & Shunts

Get to know the symbols for resistors and learn about the most common type of resistor on board: the shunt.

Fuses & Circuit Breakers

How are fuses and circuit breakers represented in circuit diagrams?

Coils & Transformers

Coils mostly occur on boats within transformers. Here you will learn about their basic function and how to represent them.

Lamps, LEDs, Diodes, etc.

In this lesson you will get to know a few more symbols for common components in a boat's electrical system.

Basic Circuits

In the final lesson of the module, you will learn how the components in boat electrics are connected in parallel and in series and how this affects battery capacity and voltage.

Cable Selection and Installation

In this module, you will learn how to choose the right type and size of cable and how to properly install it. This is crucial knowledge for anyone planning any modification on their boat's electrical system.

Cable Construction

Learn about different types of cables and which ones are suitable for use on boats.

Colors & Labeling

Learn what cable colors you can use for what purpose and how to properly label your wiring.

Sizing Cables

Learn how to choose the proper size for a cable with respect to ampacity and voltage drop.

Terminals & Terminal Installation

It is crucial for the system's safety to establish proper connections. In this lesson you will learn how to install terminals in a professional manner.

Making the Connection

Proper connections of terminals to bus bars and consumers are vital. Here you learn what makes a professional connection.

Overcurrent Protection (OCP)

In order to prevent fires due to overcurrents and short circuits, protective measures are absolutely crucial. In this lesson you will learn how to choose fuses and circuit breakers and where to install them.

Cable Installation

Learn the proper way to install cables in order to protect them from chafing and physical stress

Case Study: High Output Alternators

In this lesson we will apply what we have learned in this module to the special case of high output alternators. As we will see, there are quite a lot of things to consider.

Bonus: Nigel’s Examples

Here we show a few more examples of good or bad installations and also what happens in case of a short circuit if no adequate OCP is installed.


In this module we cover all you need to know about lead acid batteries.


Get an overview on what to expect in this important module.

Battery Safety

Even though they operate at relatively low voltages, there are significant dangers when dealing with batteries. In this lesson we cover the required safety measures.

Lead-Acid Battery Chemistry

In this lesson you will get an overview on the chemistry inside a battery and how lead acid batteries work.

Battery Construction

Here we go more into the details of the internal construction and discuss the differences between cranking and deep cycle batteries.

Battery Types

Now it's time to look at different types of lead acid batteries, such as wet cell, AGM, gel-cell and some new innovations.

Battery Efficiency

Learn about the crucial difference between amp-hour and watt-hour efficiency and how to evaluate batteries based on this.

Battery Ratings

What do the common ratings found batteries (nominal voltage, nominal capacity and cold cranking amp) mean?

Battery Failure Modes

In this lesson you will learn what the most common reasons for battery failure or reduced lifespan are and how to avoid them.

Series & Parallel Batteries

Learn how to maximize battery life when installing batteries in serial or parallel.

Sizing Battery Banks

This lesson will help you decide how much battery capacity you really need for reliable operation and optimal battery lifespan.

Lead-Acid Battery Installation and Maintenance

Learn how to properly install your battery bank and how to maintain it in order to optimize its performance.

Charging Systems

In this module we cover in detail all you need to know about charging batteries. Topics include charging profiles, charging systems, charging circuits and systems monitoring.

Failure Modes Revisited & Expanded

Learn about the most common failure modes with lead acid batteries so mistakes can be avoided.

The Water Tank Analogy

Through the analogy of a water tank with semi-permeable membranes we explain why it takes a long time to completely top off a lead acid battery.

Charge Profiles

Learn what an IUoU profile is and how the bulk, absorption and float phases increase battery life.

Fast Charge & State of Charge (SOC)

Learn strategies to reduce charging times and engine hours while at the same time increasing your battery's lifespan.

Charging Devices

Learn what to look for when choosing a battery charger, an alternator or when planning on installing renewable energy sources.

Charging Circuits

Learn about different ways to charge multiple battery banks from a single power source.

Systems Monitoring

Learn about the importance (and challenges) of proper battery monitoring.

Summary: Batteries & Charging

A quick recap on what we have learned so far in this module.

Energy Systems Design

In this module we will draw on what we have learned about batteries and charging systems to design an energy system optimized for how we want to use our boat

Energy Systems Introduction

In this lesson we introduce the BoatHowTo Boat Electrics Planner which will help us to determine the energy balance on our boat

Energy Consumption

In this lesson, we will look at all loads on the boat and determine their energy consumption for different scenarios.

Energy Storage

To store the energy between charge interval, we have to carefully design our battery banks. In this lesson we look at various options for batteries depending on our calculations from the previous two lessons.

Energy Generation

Now we look at the supply side and determine the available charging sources such as shorepower chargers, alternators and renewable energy sources and their required output to keep up with our energy needs.

Case Studies: Planning a (Re-)Wiring


Circuit Diagrams with easyEDA

Planning the Wiring

Simple Boat

Medium Boat

Complex Boat

Final Remarks & Outlook

+ free access to the BOATHOWTO Boat Electrics Planner spreadsheet tool

+ exclusive bonus lessons that will be added to the course over time

The first bonus content which is already available is a whole mini course on Alternative Energy Sources. And there is plenty more content in the pipeline!

It’s excellent value for money

Martin L. - 

Perhaps some might say the course isn’t particularly cheap but I would argue the cost versus the excellent work that has been done in the creation of the course and in my view at least, it’s excellent value for money. It is also a reminder that there are things we may think we know, until you complete the course you may well find there are things you didn’t know or had assumed differently.

So thanks for all your hard work and I do hope that many will learn better and safer ways and take a much closer look and inspection of their own electrical systems. I certainly have. There is a great deal of information to absorb and I have no doubt I will be returning again and again to re-read various sections of the course.

Ready to acquire expert knowledge
in Boat Electrics?

Take advantage of our limited-time launch offer:

Immediate access to Boat Electrics 101
for only $199 instead of $299.
This includes future course updates and bonus lessons.

100% Satisfaction guaranteed
– or get your money back

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Boat Electrics 101: More Testimonials

"Boaters know there is nothing better than a trouble-free day on the water."

"Having the confidence and skills to tackle unexpected issues makes boating much more enjoyable.
The team at BoatHowTo has put together a ‘Boat Electrics 101’ course designed with the recreational boater in mind. They will walk you through the skills and tools required to troubleshoot your boat’s electrical system. Each work-at-your-own-pace module will help you understand the basics, apply it to your existing system, then get your hands dirty.
I always say, 'learn then do,' so we can all be safe on the water."

Jeff Cote

“Great hands-on information for upgrading my system."

“Boat Electrics 101 helped me understand how to plan an upgrade to the energy system of our Moody 44 "High Flight". Thanks to Jan's great explanations, I am now confident to have a plan forward and make the the right choices when I will be sizing the new battery bank and upgrading the old alternator with a modern B2B charger."

Chris Loewe
- SY High Flight

This is the course I wish I could've had years ago!"

“This would've saved me hours of trying to figure out what the best approach is for various parts of the power setup on our Tayana 37. More importantly though, this course has given me the confidence to know that I am doing it 'right' from the start. 

I've made a lot of mistakes in the past that cost me time and money, even putting the boat at risk unknowingly. 

The content of Boat Electrics 101 is clear and easy to navigate. And Jan presents the content in an easy to follow (and even entertaining!) way.

I've noticed I feel less anxious, knowing better how things work and how to fix them myself. So save your time, money and stress! Invest in knowledge that will pay you back again an again as you cruise."

Lars Sandved Smith
- Navika Sailing / The Floating Studio

Meet the team:
The faces behind BOATHOWTO

Nigel Calder

Author of the famous Boatowner’s Mechanical and Electrical Manual, often referred to as the "bible for boatowners"

Nigel Calder

Nigel is a full-time sailing writer, with a focus on marine technical systems. He is often referred to as the guru when it comes to mechanical and electrical systems on boats.

His books are widely acclaimed by both boaters and professionals in the field. His most famous book, the Boatowner’s Mechanical and Electrical Manual has sold 300,000 copies and a staggering 4,8 stars out of 596 ratings on Amazon.

Besides writing books, Nigel is a long-time member of the American Boat and Yacht Council (ABYC) electrical Project Technical Committee (PTC) which writes the standards for recreational boat systems in the USA, and has also been involved in European standards development. He has recently joined marine energy systems company OceanPlanet Energy as a mechanism to continue his passion of constantly improving boat electrical systems.

Michael Herrmann

Author of several books about technical equipment on boats. His book on electrical systems Elektrik auf Yachten is considered the reference for technical information in the  German language.

Michael Herrmann

Michael belongs to the rare kind of people who combine a vast theoretical knowledge with the ability to apply this to the practical world.

Besides having written seven books on the topic, he has published over 500 articles in technical magazines, mainly on the topics of boat electrics and mechanics.

Since 2007, Michael has been a member of the German Boat Builders Association committee on electrics and a member of ISO TC188 establishing standards for small craft.

His latest activity in the ISO was contributing to the merger of the two basic standards for electrical systems on recreational craft - ISO 10133 and 13297.

Jan Athenstädt

Jan runs KlabauterKiste, a German online magazine for boatowners and Klabauter-Shop an online shop for boat electrics. He holds a PhD in Computer Science.

Dr. Jan Athenstädt

Jan is the youngster in the BOATHOWTO team. During his studies of computer science in Germany and the US, he has worked as crew on various tall ships before moving aboard his own boat.

He started teaching people how to install and maintain technical systems on their boat through his online magazine KlabauterKiste.

He later started an online shop for boat electric supplies which he runs from his boat while sailing the Med.

Jan takes care of the technical side of BOATHOWTO and will guide you through most of the video lessons.

What people say about us

Nigel Calder is universally recognized as the guru of yacht systems. His hardcover tomes grace the bookshelves of yachts the world over. On Isbjorn, his are some of my most referenced books.

Andy Schell ‧ Skipper of ICEBEAR & ISBJORN at

I know quite a bit about boat technology. But Michael Herrmann is a living technical encyclopedia. There is definitely no question that remains unanswered. If I hit a dead end, he is my first point of contact. He simply knows everything, and if he doesn't know it he'll find it.

Christian Haschke ‧ Yacht Brokerage & Service at

Jan has a wealth of knowledge about boats and boat systems. In particular when it comes to electrics, his online shop made him a great advisor regarding the choice of the right components and their proper installation.

Laura Secorun  ‧ Managing Director at ona ocean

Is Boat Electrics 101 really for me?

Unless you are already deeply familiar with the ISO 13297 or ABYC E-11 and other electrical standards, you will get valuable information from Boat Electrics 101!

We designed the course with both beginners and experts in mind: 

The first modules cover the basics of electricity and the basic components of a boat's electrical system. They are specifically designed for beginners who have no or very little technical background.

The later modules go deeply into the specifics of the ISO and ABYC standards and contain information that is relevant for anybody who wants to extend an electrical system or plans a complete rewiring of a boat. These lessons are interesting for amateurs as well as professional boat builders.

With exclusive access to our Boat Electrics Planner tool you can design your own system and calculate the energy balance for multiple scenarios and complex boats with up to 6 separate house battery banks.

It actually isn't only a course, but it is an evolving learning platform

Miro Peternelj

Having access to up-to-date materials on Boat Electrics is very handy for someone who deals with small boat design, like me. The best part of the whole course is that it actually isn't only a course, but it is an evolving learning platform.

The course is for you if...

  • want to properly understand your boat's electrics.
  • want to be able to spot weak links and assess the safety of your system.
  • want to be able to safely extend or even rewire your boat electrics.
  • want to be self-reliant and be able to help yourself if a problem arises.

It's NOT for you if...

  • are not willing to invest some time to do things right
  • don't care if your boat's installation is safe and according to standards
  • prefer to hire someone to do all the work on your boat
  • are never further than a few miles from the next service station

What's included in our

Online Course on Boat Electrics

  • 59 video lessons (+ an increasing number of bonus lessons) you can watch as often as you like 
  • Access to the BOATHOWTO Boat Electrics Planner
  • Extensive case studies for three example scenarios (including wiring diagrams)
  • Future bonus lessons & exclusive access to talks from Nigel

100% Satisfaction Guaranteed

Secure Payment

100% Satisfaction Guarantee

You are fully protected by our 100% Satisfaction-Guarantee. If you are not convinced by our course within 60 days of your purchase, just let us know and we'll send you a prompt refund.

Nigel, Jan & Michael

Frequently Asked Questions

I know nothing about electrics. Is the course still for me?

Can I really get my money back?

Is there a schedule for the lessons?

Will there be Q&A sessions?

I am a boat surveyor. Does the course make sense for me?

What kind of bonus content are you planning?

P.S.: If you have any further questions about BoatElectrics 101, don't hesitate to contact us

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