What source for electric energy in a hybrid system?

Hi,
for how long do you use the boat and how many days in a week ? and how many days of the week is the boat staying at the pier waiting . If the boat is used one or two days a week and all other days staying we can think about a gas/motor alternator that is feed by hydrogen. The hydrogen can be produced during the days the boat is at the pier with solarpower.
A hydrogen pressure store can store much moore energy than a batterie . Than the hydrogen can be used for the hydrogen combustion motor/alternator or in a fuel cell. Here at horizon fuel cell you can buy a 5 kw stack , need two for 10 kw. https://www.horizonfuelcell.com/h-series-stacks
Yes this is not the ceapest system as you need also a reverse fuel cell or electrolysis cells to produce the hydrogen. But at the end you will have the cleanest drive all,around as the hydrogen is all solarpower product and for duration much better that batteries as batteries waight to much. And nobody wants to carry two or moore Tesla model S packs in a faster boat.
Aske for a sponsor . for such new project to build up the clean boat drive it is possible to find A sponsor or the goverment that helps to show green know how.

Happy Amps Christian
PS: a petrol engine that is feed by syntetic fuell is also very clean , but then i would use a gear reduction to drive a big dia, efficancy propeller. I have worked on a hybrid sub drive for Italien army and i know some designer infolved in the German 212 Sub with fuel cell drive. They switch from alternator sorce to electric sorce using battery and fuel cell stack . In a sub it is ok but for a planing craft ?

 

Hydrogen production isn't free. It is more expensive than bying any other fuel of the shelf. As a system it is more expensive than li-ion batteries. One of the biggest problems with FC cars is lack of infrastructure for refueling. There are a few experimental installations of h2 generation for solar and wind power storage. But not economically viable. The only economical and practical option for domestic energy production is solar. And as energy carrying medium for fuel cells methanol would be the obvious choice. That is also why those are the comercially avaliable systems. The idea of h2 based system is dependent on local production. Which exists but is extremly inefficient and expensive. So it does not make any sense. If direct fuel cell is a must. Then methanol is the only acceptable option at this moment.

 

Hi Niclas,
yes , you are right. But if the boat has long time to charge energy a battery has limited capacity if only electric power has to be stored. Hydrogen made from solarpower is easy to store and the store self is cheap. And you can store power from windmill farming in the night when solarpower is of and wind is strong blowing. Hydrogen has some advantage over batterys and other system if you want to store cheap and a big amount of power.
Researcher at the MIT have found that also molten silicon at 2000 + degre can store a big amount of energy . You can cool it down feeding a sterling motor and you can use the bright light at this high temeratur feeding solar cells by pumping the liquide from hot to colder tank. But yes not very handy at such high temperatur.

Happy Amps Christian

 

All very interesting, and promising for the future. But at the moment, storing hydrogen is very cumbersome expensive, heavy and potentially hazardous. Espescially since leaking often is a problem. Methanol on the other hand can be transported in regular Jerry cans, has an energy density of 6kwh/kg vs max 0,2kwh/kg for the metall hydride tanks. So what's the point?

 

Sails I tell you.
The ultimate wind, and therefore, solar power (wind is made by the sun arguably).
Okay... along with a small IC engine to turn a big prop but only when needed.

 

Methanol is interesting but I know too little about the manufacturing process.

A quick research shows that methanol (pricing from Methanex) costs approximately 7 cents euro per kWh whereas diesel (my current price) is 5,5. In reality the methanol is probably even more expensive as the 7 cents is based on large quantities sans shipping (I presume) while the diesel is by the pump at the local jetty.
Also, it seems like most of the methanol is made from natural gas. Methanol consisting of current coal is much more appealing.

 

Again, "home" production and storage of hydrogen will cost you around 0,5€/kwh. So methanol will be ca 7 to 8 Times cheaper. Of course Dmfc are slightly less efficient. That will make methanol about 5 Times cheaper than hydrogen per kwh at the propeller. And methanol can be produced both from captured methane (farms and organic waste, extreemly environment positive, since methane has around 27 times worse effects on global warming than does co2). And i Think also completly synthezised. But I'm not sure. Was a while since I last checked. I know most methanol is produced from fossile fuels. But it is simply a choice, just the way you can choose 100% bio methane when filling up your cng car.

 

Can you point me in the direction of a dmfc manufacturer that have a solution in the 30-40 kW range?

 

Hi Magnus,
sorry for my late response, One of the leading dmfc are , Company - SFC Energy https://www.sfc.com/en/company/ .

Happy Amps Christian