Fuel cells and electric motors

Makes it interesting to have ocean full of fuel!!!!!!!!!

Info about this here I found http://www.landfallnavigation.com/fuelcells.html

 

Just as interesting as where to get the energy to convert the ocean to fuel.

 

Who needs fuel, wind can provide speed, joy (winning), anger (losing), fear (oupps, storm!), electricity - everything

 

The use of fuel cells as a power source for boats is quite an intriguing one.
Where HaveBlue (mentioned in the link on post 1) seems to fall short is the thermodynamics. There is a tendency among advocates of new technology to think "well, it's not combustion, so thermodynamics doesn't matter". Wrong. The same fundamental laws of nature apply to all energy conversion systems. Conservation of energy, for instance. The increase-of-entropy principle. A 50 watt solar panel and a 250 watt wind turbine might, in perfect conditions, net you six kilowatt hours a day. 3 kWh a day would be at the high end of what I'd consider realistic. Factor in the inefficiencies of running a watermaker and electrolyzing that water, storing the resulting hydrogen under pressure (it ain't easy!), converting it back to electricity, losses in the motor and its controller.... it's an interesting idea, but energy isn't going to come out of nowhere and unless you turn your boat into a floating solar panel, you're not going to be generating significant amounts of hydrogen on your own. Sometimes you need to step back for a moment and just work out the energy and exergy balances on your radical new system, before too much money gets spent on the wrong things.
That said, I do think fuel cells will find their way into boats. We need to find a way to get rid of the expensive platinum-based catalysts and other exotic stuff that jacks up the initial cost. We need to find a way to either store hydrogen effectively, or reform liquid biofuels such as methanol on board the vessel. And we need to get a distribution infrastructure going for these fuels. Big challenges, and the car industry is really pushing development on all three points, but we will eventually see fuel cells finding their way into boats. Just probably not in the self-contained form of HaveBlue's project.

 

http://www.max-power.com/fuelcell/

 

Fuel cells generate heat and are not really powerfull for their weight. It would be so much better to burn the hydrogen as fuel in a recipricating engine.

If you are going to collect solar and wind power to convert seawater to hydrogen fuel you are looking at inefficiencies loss of around 80% when it finally becomes electricity. Why not bypass the entire process of generating hydrogen and storing it, and just store energy in batteries and drive the engine direct?

The only time hydrogen will be usefull is when the natural gas supplies are finished in around 40 years time, and then the existing gas network can be converted to hydrogen. The fuel cell will work as a microgenerator for each home, generating electricity more efficiently than through the grid, and the byproduct of heat can warm the house and preheat the water for the boiler.

The grid energy transmission causes about 40% loss in actuall generated electricity. Micro generation in the home will result in near zero loss, as the electricity is only produced on demand. Heat energy from electric power grid generation is lost to the environment whilst micro generation heat is used in low temperature heating systems like under floor heating, and the surpluss heat can preheat the boiler for bath and cleaning hot water, reducing the energy requirement.

Central power stations nuclear/tide/wind etc will be used to create hydrogen on a massive scale and use the gas pipework system to pump it into the homes where it will be a clean fuel.

That is the future of fuel cells

 

"Voller Energy, the UK based fuel cell specialists are leading the way in future yacht design with a concept yacht that is completely powered by fuel cell technology. Voller Energy teamed up with the internationally acclaimed yacht designer, Ken Freivokh to develop a ground breaking model and modern ‘way of working’ for future yacht design. This study concentrates on a 55 foot concept cruising yacht powered by a 5 kilowatt fuel cell."

More at: http://www.bymnews.com/news/newsDetails.php?id=17891

Also:
http://www.voller.com/applications_mar.asp
http://www.freivokh.com/page/voller

Cheers.

 

All very nice but as also posted, where does the energy to make the fuel for the fuel cell come from?

 

LPG.
The more intriguing part of it is only having available 5 kW for everything, including propulsion. We are talking of a 15 ton yacht...(?)

Cheers.

 

Just a few comments about fuel cells. I’ve personally been in the field for almost 20 years now and have experienced the promise and cold hard reality of power generation for a long time.

As has been pointed out, fuel cells are energy conversion devices – they convert energy from one form to another. For example, traditional reciprocating engines convert chemical energy into kinetic energy (motion) and thermal energy (heat). The kinetic energy can then be converted via an alternator (generator) into electrical energy (and more heat) which can then be used or stored in batteries (chemical energy again). Fuel cells convert chemical energy into electrical energy and heat. In general, fuel cells are more electrically efficient than a comparably sized engine/alternator by about a factor of two at small sizes (under 5-10 hp or 3-5 kW). At very large sizes (central power generation models), the efficiencies tend to be pretty similar.

Both engines and fuel cells require fuel to operate. Traditionally, that fuel will some sort of hydrocarbon fuel either natural gas, propane, or a heavier liquid fuel such as diesel or kerosene. In the power generation field, hydrogen is generally not considered a “fuel” because it cannot be mined or pumped out of the ground – it’s considered an energy carrier similar to electricity that is produced in one place and then transported for use. Suffice it to say that all chemicals can be converted into other chemicals efficiently if the price is right. Methane to diesel, coal to methane, etc. are all “known technologies” that can be performed at scale as necessary. This includes a range of alternative ‘renewable’ approaches including fermentors, anaerobic digesters, pyrolysis reactors, and gasifiers, etc.

There is a school of thought (mentioned above) that suggests using nuclear power to produce electricity and heat that could then be used to produce hydrogen via electrolysis and transport the hydrogen. The problem with that model is that hydrogen as a molecule is difficult to compress, store, and transport from an energy standpoint (safety is not a serious issue) and if you’re going to go to that trouble, why not just transport the electricity directly? The general response is that the heat generation from a nuclear plant is significant (~80-90% of the total 'nuclear energy’ that was available from the fuel in the first place in all but the most modern schemes) and generally wasted so why not use it for something?

Now the cold hard reality of energy generation – cost. Internal combustion engines have been in wide distribution for 80+ years and the investments in research, manufacturing scale up, process optimization, etc have essentially occurred. The turbine industry is much the same. Sure there are new developments here and there but the heavy lifting is done and the costs are spread over the industry now. Nuclear is nearing that stage and the defense industry already spent the TRILLIONS of dollars to scale up the processes and understandings to the point where commercial systems are ‘known’ technology.

How much will the average consumer spend for ‘more efficiency’? The answer is generally not one penny. Individual buyers may be interested but the ‘public’ at large does not care about efficiency – not with their pocketbook. The public wants OTHER people to spend money to be more efficient but not themselves. Complete systems have to compete on their final costs from day one. That’s true of most technologies, not just fuel cells, and is the “Valley of Death” faced by most new technology. Hybrid vehicle options have been around for 40+ years but only in the last five have commercial vehicles been available. Why? The answer lies in laptop batteries and better control systems. The hybrid car needed a cheep supply of efficient, lightweight batteries and had to wait for the computer industry to pay for the development.

Personally, I can’t think of any technology that hasn’t sat around for several generations before finally finding it’s way into the commercial market. Public cellphones celebrate their 35th anniversary next year for example and that doesn’t include the military use before hand. Fuel cells will be the same. Sometime in the next 20 years (hopefully sooner - my kids need their college tuition!) fuel cells will become entrenched in some application and will flow out from there. My personal opinion is that boating will not be an early adopter but perhaps the high-end yacht market.

 

Thanks Milliken, Very interesting and enlightening reading. My brownie points are posted