Book Review: Solar Electric Boats: Plan, Build and Benefit

Solar Electric Boats: Plan, Build and Benefit is a comprehensive and informative guide written by someone who knows the subject matter inside and out and is working each day to “enable and empower the transformation of our world to one where the electric power generated from green sources runs the entire transport system”.

Author Sandith Thandasherry is the man behind Navalt Solar Boats and the Aditya solar commuter ferry that won the first Gustave Trouvé Awards for Electric Boats and Boating in the category ‘Electric Boats Designed for Paying Passengers’.

Solar Electric Boats author Sandith ThandasherryThe Aditya is quite remarkable and inspirational. It was launched in Kerala, India, in 2017 and as of its 4th birthday it had transported over 1.35 million passengers and covered 80,000 km without using a single drop of fuel. The cost is about US $2.60. No, that is not the cost of a fare – that is the cost PER DAY to recharge from the local grid, with the rest of its energy coming from the solar panels on its roof.

Thandasherry worked closely with various levels of government to develop, fund, build and operate the Aditya. His background and degrees – a Bachelor in Naval Architecture and MBA from highly respected international business school INSEAD – served him well, and also serves the readers of his book well.

Solar electric boats – physics and finances

With the mind of an engineer Mr. Thandasherry clearly outlines all of the aspects and details that need to be considered for the physics of a solar boat. At the same time he brings the experience of an entrepreneur who achieved success by understanding the needs and desires of both private investors and government officials.

The charts, research, and facts and figures are laid out clearly, concisely and without bias, but also with a passion for proving that the endless supply of energy from the sun provides a better source of energy than burning oils. 

The organization of the book make for easy reading and reference. It starts with the basics of what exactly is meant by the term ‘solar boat’ and his reasoning for ‘Why we need solar boats’ and proceeds to practical matters with chapters covering Technology, Design, Construction, Testing and Quality Assurance…right through to Operations and Maintenance.

Solar Electric Boats Chart of OPEXAlong the way there are various charts that illustrate the advantages of solar boats in terms of CAPEX, OPEX, FOREX  and TCO. Wondering what those terms mean? Mr. Thandasherry understands that not everyone is as familiar with these terms as he is, so acronyms like these are explained, and there is a thoughtful list of abbreviations right up front (which I admit I had to refer to a few times!)

There are also charts and data in each chapter to illustrate what you need to know about nearly every aspect of planning and building a solar electric boat. Some examples: the relationship of speed, power and system type, benefits and disadvantages of different types of solar panels, solar production of a panel throughout the year, energy plots of a solar ferry like the Aditya and more.

Data and recommendations are provided for things like how to analyze what amount of energy will be needed for the boat, how much can be derived from the sun in terms of solar panel size, what batteries are required and what is needed from the grid or even an (eek!) fossil fuel genset.

Solar Electric Boats - three solar panelsI am not a naturally geeky person who likes poring over those kinds of numbers and data, but I found the book easy to read by skimming over the charts and graphs, then reviewing them in detail when I needed specific knowledge.

Practical, hands-on advice also is provided on things like different system configurations, reducing the weight of a boat and designing it for maximum propulsion efficiency and there is also a section on how design of the overall look of the boat as well as the passenger and cockpit sections play important roles.

Covers small, medium and large solar boats

The foreword of Solar Electric Boats says that “the primary target is the marine transport system’s decision makers, advisors and team, who need to understand the fundamentals of solar-electric boats“, but in my estimation this book is beneficial to anyone who is thinking of a solar electric boat for any use, leisure or commercial.

It is written with three sizes and applications of boats in mind: leisure boat (10 passenger capacity), cruise boat (30 passengers) and ferry boat (75 passengers).

Solar Electric Boats - schematic of systemIn the end, they all need to move through the water using solar electric power, so the learning can be applied to each. Certainly the OPEX (Operating eXpenses) and TOC (Total Cost of Operation) are important for a commercial solar ferry carrying 75+ passengers, but they are also important for someone who is looking to escape the grip of fossil fuels in their own leisure boat activities

Aside from Plugboats, I also administer and monitor the Electric Boats forum on the platform. There are many threads about exactly the kinds of things covered in Solar Electric Boats – Plan, Build and Benefit and I can say that this book provides well researched information applicable to many of the questions brought up on the forum. Appendix 2, which charts day by day solar output, motor consumption and resulting battery charge, will be particularly relevant for some.

For the novice, expert, builder and/or investor

Finally, I will provide my full disclosure. If you click on the link and buy this book, I will get a small commission, but that is not why I am recommending it.

solar electric boats vs diesel - cost of operation

I hope you buy it because I think solar electric boats can make the world a better place. I have felt for many years that if the world is to change and rid itself of the continuing and increasing problems caused by the accumulation of carbon in our atmosphere, the two keys will be the 1: electrification of all motors and 2: the harnessing of solar power to provide the required electricity.

In the marine propulsion field, the Aditya and other boats powered totally or in part by the sun’s rays are on the rise. Six out of eight winner’s in this year’s Gussies electric boat awards included solar power components, and for his part Mr. Thandasherry and his companies Navalt and Navgathi are leading a marine solar revolution in India, with dozens of solar ferries, water taxis and fishing boats being built or in development.

So for those who are considering solar power as an option for a boat, whether you are planning to be the owner, designer, manufacturer, investor or government authority considering a project, Solar Electric Boats – Plan, Build and Benefit is for you.

It is one of those books that achieves two goals. It is general enough to be understood by the novice, but also detailed enough to provide food for thought and specific guidance for the expert.

Jeff Butler


Purchase Solar Electric Boats – Plan, Build, Benefit

Leave a comment

Axopar 25e Gussies Award Winner

Get all the latest electric boats and boating news delivered to your mailbox!

Sign up here for the Plugboats newsletter.


No, thanks.