Solomon Technologies - "Electric Wheel" electric motor propulsion systems

[philv]

For the first application (ferry in toronto) a quiet and green alternative to the huge battery bank is maybee a mcro turbine :
http://www.capstoneturbine.com/prods...ucts/index.asp

Since you will have to heat the boat some part of the year, you could use that microturbine to do so and have it charge your battery bank.

The weigth of the smaler turbine (off grid) is more than 500 kg.
This limit the marine applications but the product is great :
Electricity generator oil free and almost maintenance free...

[brian eiland]

Originally Posted by philv

For the first application (ferry in toronto) a quiet and green alternative to the huge battery bank is maybee a mcro turbine :
http://www.capstoneturbine.com/prods...ucts/index.asp

The weigth of the smaler turbine (off grid) is more than 500 kg.
This limit the marine applications but the product is great :
Electricity generator oil free and almost maintenance free...

This company is the same one that was employed to provide the small turbine/generator for the Super Flywheel Patriot LeMan's Race Car that Chrysler was working on:

The Patriot hybrid-electric racing car
Chrysler designed and built a hybrid-electric, turbine-powered, liquid natural gas-fueled racing car for racing; the company said it could reach 200 mph for short durations, with competitive handling. The powertrain included a two-turbine alternator, an ultra-high-speed flywheel and an electric traction motor. All components were water-cooled.

The traction engine was a four-pole, three-phase, 525-volt AC induction motor, weighing 143 pounds, with a maximum speed of 24,000 rpm; it had an aluminum housing, was lubricated by oil, and had an 8:1 motor to final drive ratio.

The turbo-alternator was a compoounded twin-spool turbine with two alternators, fuled by natural gas, with a 100,000 rpm high speed and 50,000 rpm low speed; an intercooler was placed between the low and high speed compressors. A single point combuster was used; the alternators were three-phase AC induction. The whole thing weighed 186 pounds and was water-cooled; materials used included composites, ceramics, titanium, and stainless steel.

I brought up this 'flywheel energy storage' subject on several postings here

[gregzw]

Do you know of anyone who has used your electric engines as an addition to an existing gas/diesel engine?

The purpose being to use the gas/diesel engine to get up to planing speed and use twin electric engines to maintain the plaining speed. My understanding is that it takes less than half the power to maintain planing speed than to get to planing speed.

You could also use the electric engines as "re-generators" when running on the gas/diesel engine. Hopefully doing away the the need for a diesel generator.

Perhaps this could work on a smaller catamaran like the 23' C-Dory.

Greg Zwick

Originally Posted by ewhel

Gentlemen...First...our motors are designed to be capable of 4KW (6HP) at 120VDC....that means you can actually get more power out of them at 144VDC (but we limit the control so you can't...sorry!...they last longer). Depth of discharge is really independent of voltage...but for one principle...in watts ...voltage and current are inversly proportional...and...the true measure of how much depth of discharge you can get on a battery without doing damage to it is current....lower current and you can discharge them lower. To blanket applications with generalized statements doesn't work with lead acid accept when you talk current. Batteries do not like high current draws....that's why we went to a higher voltage. 4KW...at 24VDC=166amps(bad do not discharge more that 40-50%).....at 120vdc=33amps(much better and you can take them down to 60%)....at 144vdc=27amps (even better still and we have taken them to 80% without any damage). It' all in the current...actually we recomend to our users that they only do this in emergency and when they do reduce the throtle control to 2KW(or about 13.5 amps) so damage is prevented. More volts actually yields larger depth of dischare because of reduced amperage to produce the same power.
Also....we are not trying to send every one out there with just batteries! 3/4 of the boats we have done todate are diesel electric hybrids...think about this.....a 4KW diesel generator weighs in at about 200 lbs. with fuel (or 3 group 31 batteries). This means you could go with less amp hours for normal operation but still have the ability to have unlimited motoring if necessary. The key is NORMAL, or cycle of use, or mission profile, or standard operational scinario. The size of the generator(or shore charging capability) and batteries are both on a sliding scale. You must first figure out what your cycle of use is. Also, there is no where in anything I have read or experienced that indicates if you use 30% of the batteries power that it comprises a whole cycle. We have AGM that have been routinely charge and discharged to 40% hundreds of times with no degradation in performance at all.
This is not how FF motors work and there is more to think about.....BUT....you can taylor a diesel electric hybrid/electric system to your specific needs and minimize energy usage or increase energy usage with more power and ammenities. I personally chose more power....Yes I have a 28 ft. sailboat with TV/VCR, Microwave, electric stove, refrigerator, stereo and electric back masager......for me more power.

<Admin Edit: Post moved into the main thread>

[brian eiland]

I was going to just make an additional reply to this older subject thread, but it appears to have strayed off subject in several instances, so I thought a new begining was applicable considering the fellow who really brought this relatively new technology to the yachtng scene has also a new begining.

Originally Posted by ewhel

HI Folks....David Tether here. Have been forwarded a bunch of email stuff that suggested you all had questions....so I checked in and logged on! Having read the emails with interest I will submit one basic premise....We have studied this something fierce for 6 years. Several basic things about fossil fuel motors...they are here to stay for awhile because it is hard to achieve the power densities with any other medium(and the big three/Oil companies won't let you any way), Fossil fuel motors are over rated(motor torque rating at some RPM where you can't use it constantly, Parasitic losses are on brand new pumps, impellers, alternators (with charged batteries) and with new belts, they are oversized to be able to push a prop at start-up rpm's, and anyone that thinks the average boat transmissions are 98% efficient needs a new drug. Also...through there support systems have to be entirely variable and have Idle capability
Having said this....the average generator, because it is ballanced and blueprinted to make electricity with a ballanced load can convert fossil fuel into electricity at about 45 to 70% efficiency. Now the battery pack becomes your second fuel tank and allows the generator to only run at it's optimum efficiency. The battery pack is your source for quick, on demand high demand, current draws. What happens is that whenever you use fossil fuel it is always converted at the highest efficiency. This also allows one to adjust the batteries and generator to the mission profile....large batteries with small gen...small batteries with large gen...small batteries with small gen....large batteries with large gen.
Didn't want to ramble on just a beginning primer....

And then his new website:
E Motion Hybrids

Been There, Done That

Although it’s taken a quantum leap forward in sophistication, Tether’s basic
system has been around for some time. Years ago he founded Solomon Technologies and helped pioneer hybrid-electric propulsion technology for sailboats working from a ramshackle collection of waterfront buildings on Maryland’s Patuxent River. There he developed a plug-in hybrid-electric system for boats more than 15 years before General Motors was able to do it for cars like its Chevy Volt.

Unfortunately, the revolution got sidetracked temporarily. In 2004, Tether received a welcomed injection of capital from a group of outside investors. But the new relationship went sour, a nasty breakup ensued and he found himself on the outside looking in – no longer a part of the company he had founded.

Nothing if not determined, he sat out his contractual non-compete period and started over in Fort Myers Beach, FL, with Electric Marine Propulsion.

New Subject Thread
Hybrid Electric Propulsion for Boats, Diesel-Electric, etc