An Italian hydrojet to revolutionize electric boats?

DeepSpeed, an electric hydrojet engine used as an outboard rather than an inboard is causing a stir at the Genoa Boat show this week with its efficiency and speed results.

The concept came about because the price of replacing a V8 fossil fuel motor on a boat owned by DeepSpeed founder William Gobbo in 2007 got him thinking that there must be a better, cleaner solution to getting  a boat through water.

He looked at electric motor options and saw they all had propellers which then got him to wondering why there wasn’t anything like a jet engine as an option. After all, airplanes had ditched propellers for turbines decades ago. There must have been a reasons. Why was boating still stuck on propellers?

Assembled an international team of experts

Sr. Gobbo’s expertise was actually in the banking and information management industry, not engineering, so he began to ask others who did know engineering and gathered a team around him that now includes experts in fluid dynamics, mechanics, electronics, computer science, design, communication and prototyping. They come from six countries and there there are 2 professors, 2 researchers, 11 engineers, 4 designers, an 1 F1 H2O powerboat pilot…and most importantly, one luminary.

The luminary is Professor Ernesto Benini of  the University of Padua a leading international expert on fluid dynamics experts applied to aeronautical propulsion.

Gobbo went to see Benini in 2017, after committing almost a decade and considerable amounts of money to formulate and validate his theory and commission engineering drawings and plans.

“I knew I had something“ he told Italian business daily Il Sole 24 Ore “but I needed scientific bases to support my intuition.

Potential was immediately apparent to the professor

Professor Benini immediately saw that the idea of positioning a water jet engine as an outboard overcame all of the limits of traditional water jet propulsion systems (whether gas powered or electric)  which were all positioned inside the hull of the boat.

The biggest difference is that the inlet flow of water becomes dynamic. With jets inside the hull the flow is static, determined by the motor only, but with an outboard jet the water flowing through the jet as it moves through the water creates a dynamic flow: it increase with speed. In essence the faster the boat goes…the greater the flow…the faster the boat goes – and with increasing efficiency.

The difference in efficiency compared to a propeller is even more stark, as this chart shows.

“When I entered Professor Benini’s office”  recalls the entrepreneur “I found a professor of fluid dynamics with courteous and reserved ways. When I left I saw a boy full of enthusiasm”

So much enthusiasm that Benini immediately joined the team, which resulted in increased interest from investors and Italy’s scientific community as a whole.

In 2018 the DeepSpeed propulsion system achieved “Seal of Excellence” certification from the European Union’s Horizon 2020 department, which is only given to 3 out of 1,000 applicants. This in turn has led to investments of almost €1.2M  from various Italian and European science, technology and startup funds. They are in contention for a Horizon loan of €2M and DeepSpeed’s facebook page has notification of a crowdfunding effort, but no details have yet been posted.

Buzz at the Genoa Boat Show

Which brings us to this week, at the Genoa Boat Show, where Sr. Goddo and his team have been showing off their prototype to enthusiastic crowds. The model on display is the company’s Number 10 prototype, and while it is very secretive about specifics of development, it seems safe to say there has been improvement every step of the way since 2007.

The advance of electric boating has always been marked by innovative thinking. Accumot and then Torqeedo put the electric motor under water, Candela has successfully pursued the potential of hydofoiling.  And countless others are continually taking smaller, but equally important steps in every aspect of making electric boats go longer, faster and more efficiently.

Who knows, maybe a waterjet on the outside of a boat is another  one of those ‘let’s start with a clean sheet of paper’ ideas that will propel (pun intended) electric boating even more quickly into widespread adoption.