Energy Observer Boat... Solar/Wind Over Hydrogen Efficiency

[JeepHammer]

A former customer sent me this link (and others) and wants some idea of how this could be adapted to small cargo delivery throughout smaller islands.

I don't know crap about hydrogen electrolysis or fuel cells, but if this is correct they are way more efficient than fossil fuel engines.

Any USEFUL ideas on the subject?

 

[sunshine_eggo]

Hmm. USEFUL? By "useful," do you mean only positive spins in the desired direction, or data that yields a conclusion even if it's not the desired outcome?

First thing to realize is that this boat has no cargo function and is only a technology test bed that is HIGHLY specialized.

Second thing is that every single conversion of energy results in an efficiency loss. Direct use of PV output is dramatically better than conversion to hydrogen and then burning or running through a fuel cell. Typical electrolysis process is only about 75% efficient... and then you run it through a fuel cell... to get electricity at about 60% efficiency... so 0.75 * 0.60 = 45% efficient to go from electricity to hydrogen to electricity.

Monumentally fucking stupid unless you hate electricity and only want to use 45% of what you produce.

Some numbers:

28kW of solar = 38 hp at peak output
Assuming 4.5h/day of peak solar = 126kWh/day
Assuming 12 hours of operation per day, 10.5kW or 14hp continuous for 12 hours.

Add some "sails" and get some "free" wind energy. Use any surplus (at the expense of speed) to run the engines in reverse and generate electricity to produce hydrogen.

Worth noting that even though they indicate a 1700kg storage system with 1000kWh of energy (equivalent 30 gallons of gas), they also indicate that to date, they have generated "more than half a ton" of hydrogen, or something north of 500kg - not even enough to fill 1/3 of their storage capacity.

Summary:

With a PV array capable of delivering the equivalent of 14hp continuous for 12 hours/day and a couple of funky sails, they have generated the equivalent of about 10 gallons of gasoline worth of hydrogen.

Putting sails on a boat helps reduce it's propulsion demand, but I bet they really hurt PV production.

I see ZERO practical applications for cargo delivery, ESPECIALLY for small applications.



Interesting website info:

Energy balance from Singapore to Thailand

It took us 8 days of sailing to reach Thailand from Singapore. Facing the absence of sun and wind for 5 days, hydrogen once again proved to be an indispensable ally in the ship's energy mix!

www.energy-observer.org

It took them 8 days to go 755 nautical miles from Singapore to Thailand at an average speed of... 4 knots... and they had to CONSUME on board hydrogen while producing NONE to make this happen, i.e., they relied on a consumable to get them there due to poor wind conditions.

Review of the 15,000 nautical miles of navigation in 2021

In 2021, Energy Observer has broken its record for the longest navigation! Back on 15 000 nautical miles of navigation, from the Atlantic to the Pacific Ocean.

www.energy-observer.org

15,000 nautical miles in 2021... generated 1% hydrogen while consuming 17% and 44% of total production came from sails.


The nerd in me thinks this is awesome. I would have loved being on this project... as long as I knew the backers were 100% okay with no ROI and were doing it for pure science.

 

[JeepHammer]

Hmm. USEFUL? By "useful," do you mean only positive spins in the desired direction, or data that yields a conclusion even if it's not the desired outcome?

First thing to realize is that this boat has no cargo function and is only a technology test bed that is HIGHLY specialized.

Second thing is that every single conversion of energy results in an efficiency loss. Direct use of PV output is dramatically better than conversion to hydrogen and then burning or running through a fuel cell. Typical electrolysis process is only about 75% efficient... and then you run it through a fuel cell... to get electricity at about 60% efficiency... so 0.75 * 0.60 = 45% efficient to go from electricity to hydrogen to electricity.

Monumentally fucking stupid unless you hate electricity and only want to use 45% of what you produce.

Some numbers:

28kW of solar = 38 hp at peak output
Assuming 4.5h/day of peak solar = 126kWh/day
Assuming 12 hours of operation per day, 10.5kW or 14hp continuous for 12 hours.

Add some "sails" and get some "free" wind energy. Use any surplus (at the expense of speed) to run the engines in reverse and generate electricity to produce hydrogen.

Worth noting that even though they indicate a 1700kg storage system with 1000kWh of energy (equivalent 30 gallons of gas), they also indicate that to date, they have generated "more than half a ton" of hydrogen, or something north of 500kg - not even enough to fill 1/3 of their storage capacity.

Summary:

With a PV array capable of delivering the equivalent of 14hp continuous for 12 hours/day and a couple of funky sails, they have generated the equivalent of about 10 gallons of gasoline worth of hydrogen.

Putting sails on a boat helps reduce it's propulsion demand, but I bet they really hurt PV production.

I see ZERO practical applications for cargo delivery, ESPECIALLY for small applications.



Interesting website info:

Energy balance from Singapore to Thailand

It took us 8 days of sailing to reach Thailand from Singapore. Facing the absence of sun and wind for 5 days, hydrogen once again proved to be an indispensable ally in the ship's energy mix!

www.energy-observer.org

It took them 8 days to go 755 nautical miles from Singapore to Thailand at an average speed of... 4 knots... and they had to CONSUME on board hydrogen while producing NONE to make this happen, i.e., they relied on a consumable to get them there due to poor wind conditions.

Review of the 15,000 nautical miles of navigation in 2021

In 2021, Energy Observer has broken its record for the longest navigation! Back on 15 000 nautical miles of navigation, from the Atlantic to the Pacific Ocean.

www.energy-observer.org

15,000 nautical miles in 2021... generated 1% hydrogen while consuming 17% and 44% of total production came from sails.


The nerd in me thinks this is awesome. I would have loved being on this project... as long as I knew the backers were 100% okay with no ROI and were doing it for pure science.

I'm not a 'pie in the sky' type person, I don't get emotional either way. It either is, or it isn't. Political slant has no place in science or engineering.

This would be a retrofit of a 100+ foot (103 feet i think) aluminum hull, beaching cargo/ferry catamaran. Holds one big truck/trailer or two 40 foot shipping containers.

It was a research platform for the Australian navy at one time, several were built as landing craft, and some haven't seen service, this particular customer sailed on one, fou d out about the rest and found out they are for sale fairly cheap.

It's diesel over electric now, diesel direct drive with electric thrusters, etc.

It's almost flat/arched top now, air burst protection for the cargo deck, almost the entire top surface could be solar with very little work... Or so this guy thinks...

My first question was "How much does it weigh?" Answer; "No idea..."

Not exactly my field of expertise, so I'm asking...

 

[sunshine_eggo]

According to the wiki, energy observer is 99.7 ft long and 42 ft wide. Let's say you covered it perfectly with 21% efficient solar panels... That's 82kW (109 hp) at peak output.

Using the same calculation, assuming 4.5 hours of peak solar and 12 operating hours per 24 hours, that's 41hp continuously for 12 hours.

I think those horsepower numbers might be enough to give your former customer an idea of the scale of power.. $50K worth of panels and controllers can deliver 41hp continuously for 12 hours. This doesn't consider the cost of a bunch of batteries either.

Not even going to bother with the hydrogen stuff. It's just absurdly useless.

 

[JeepHammer]

According to the wiki, energy observer is 99.7 ft long and 42 ft wide. Let's say you covered it perfectly with 21% efficient solar panels... That's 82kW (109 hp) at peak output.

Using the same calculation, assuming 4.5 hours of peak solar and 12 operating hours per 24 hours, that's 41hp continuously for 12 hours.

I think those horsepower numbers might be enough to give your former customer an idea of the scale of power.. $50K worth of panels and controllers can deliver 41hp continuously for 12 hours. This doesn't consider the cost of a bunch of batteries either.

Not even going to bother with the hydrogen stuff. It's just absurdly useless.

I worked on a hydrogen combustion engine project that lasted for about a minute back in the 90s, really no point to it except they paid me.
The dyno doesn't lie...

The volume of hydrogen it took to make any horsepower at all barred any reasonable usage by internal combustion.

The boat... He got the big idea because it was diesel/electric and immedately thought this might be some kind of conversion, I kind of dropped the bad news on that unless he thinks it will run on thrusters which are mostly electric.

The only way I see hydrogen being effective is fuel cell/electric, but you would need a nuclear reactor to produce enough electricity for electrolysis separation,
AND... If you have a nuclear reactor producing electricity, wouldn't you just use the steam/electricity directly?
(See aircraft carriers and nuclear subs)

Test beds/prototypes are a long way from finished products, but it looks good on BoobTube.

The Energy Observer was a racing boat, the reason I asked about weight. A military landing craft will be a crap ton heavier right out of the box.
80s military wouldn't think 2 seconds about ditching fiberglass and functional carbon fiber was a stealth aircraft secret...

He wanted an opinion, and barring some relivation, and mine hasn't changed much, I think it's impractical at best and won't work at all at worst...