The New Age of Sail


(noboxes) #135

Yes! And the ratings are based on them being cool and in high intensity laboratory light conditions simulating the equator, sun directly overheard!

If you have 5 hours of direct sun, and at hour 2.5 you have the panel aimed right at the sun, you’ll probably get 250w from a 350w panel for the 5 hours. But if you then turn the boat around the panel will be aimed away from the sun.


(bill mapezzi) #136

Well screw the 10 knots then. Electric is good for onnly a reliable 5knots, 7 if you want two wag a "trailer around, Maybe 8 or 8 1/2 if the trailer is big enough and you had all lithium batteries.Too slow and expensive. Tracking would add a lot more weight/windage/cost. Better off with sails and tow a water generator…


(noboxes) #137

Park for two days to charge the batteries, then drive the boat the third day? I don’t know tho, i cannot get past the battery cost. But, batteries beats solid lead ballast for storing power. If the lead-acids last only a year, is it worth it?


(bill mapezzi) #138

No, not worth it. I had estimated battery storage at 120% of the of a full days worth of storage at 50% only capacity, So they should get 2000 days or 10 years whichever comes first of running time since they might only get discharged 25-30% on a long cruise and at 10% discharge should have an 70 knot range now that the speed is reduced to 8knots or so being under powered and all. Basically I posted, not as a design I would want, but as the best I could come up with considering there was interest in an electric boat. In reality it supports your experience in electric powered vehicles and realistic estimate of the true lack of potential in electric powered boats in general. Diesel electric great but stand alone for long range “sailing”? Buyers choice, not mine. Like you said 36 x 12 volt lead acids would at best get 50 hsp-hours. I doubled the amount of battery storage…didn’t I? My truck batteries (29D) deep cycle read 125 amp hour, I don’t remember AGMs getting any more, just double - triple the cost. Complete “seat of the pants” estimate on resistance added due to the “trailers”, but I have built a dozen or so skinny motorboats to estimate accurately the resistance of them at different speed ranges, and I know how to use torque/RPM/hsp curves and true propeller charts, not the bs prop calculators.


(Marc Hawk) #139

I have been thinking about this topic for the last 6 months and I have the design ready. You are right, the batteries are very expensive at this time. $1,000 a KW for light marine grade lithium ion batteries. aka 30k for 30.5 kw battery which weighs 500lbs. I can’t afford it, but some people can and they need to start buying to bring the price down. I have a potential buyer in Gibralter and another guy in Florida who is building an all electric Aquila 44. In truth the sweet spot is a 40’ catamaran that displaces less then 30,000lbs. Maine Cat P-47 is probably the best choice. 1.2 million will get you an all electric boat that can do 15 knots or 8 knots all day. Add 300sqft of solar which would give you 30kw in a day and you can cross the atlantic averaging 4 knots. Add station keeping and you are ready to seastead anywhere for an unlimited amount of time.


(noboxes) #140

I think you can make 4 knots from Tampa to UK if you drop a drogue into the currents (the water currents, not the electrical ones). Pretty sure you cannot do the reverse trip if the best you can do is 4 knots. Solar recharging may be iffy in UK in winter too, so planning is needed.


(Marc Hawk) #141

You take the route past the azores and sailors only average a few more knots.


(Marc Hawk) #142

Also the 4 knots its average over 24 hours. Its probably better to go 7 or 8 during a sunny day and simply stay on course at night.


(Marc Hawk) #143

image @chinaseapirate Shuttleworth has a good design for folding out panels.


(noboxes) #144

<cough>
The $16 million MS Turanor Planet Solar :


(bill mapezzi) #145

Wow,an 85 ton 4 passenger boat that does 7 1/2 knot on its own power. at only 16 million…what a deal::sleeping:. I’ll see if I can find the shuttleworth specs without paying 10 bucks for study plan. If I had to buy one I’d still go with my off the shelf plywood/strip plank combo for 450k. 80 ft and room enough for 49 pax…Maybe im wrong and LiPo4s are not $300/kwhr … but if they are I’d get those so 600k. and save 12 tons.


(bill mapezzi) #146

Really the Planet Solar is a poor design. Seaworthy great, they have a big monohull hanging in the air to plane over a lot of big wave interference…but if it only carriers 4 passengers and a lot off wetted surface. They should have went with a foil stabilized SWAM. A submarine with three big surface piercing foils attached to three floatation pods connected by vacuum tubes to get from one to the other. Only sacrifice is you have to inflate some airbags on one side of the sub to get to the hatch and do motor/battery repair/modification/maintenence on a tilt, but other than that, drag drops maybe 66% from their design and it looks like the starship enterprise instead of an insect.


(noboxes) #147

Like a 6X4 or 5U4 or 50C5 or 6146? Sounds really fragile. But really, what do you mean?


#148

Instead of regular batteries, Redox flow batteries save on weight by storing the charge in the fluid. So, 2 recirculating tanks can be in use charging(solar?) and discharging through a second set of plates at the same time.

ConclusionsIn this work we demonstrated the possibility of storing solarenergy in a simple way using a vanadium redoxflow battery(RFB) and a CdS photoanode; unbiased charged of a solar-RFB (CdS(s)|V3+,VO2+||V3+,V2+|Carbon Felt(s),E0=0.6VNHE) was achieved. A good semiconductor/electrolytematch was achieved allowing the unbiased solar charge ofa RFB up to high state of charge (SOC). CdSe protective overlayer had a twofold increase with photocurrents up to1.4 mA cm2with no external bias. A tandem systembattery using a dye-sensitized solar cell was also studiedto provide necessary photovoltage to charge a standard allvanadium redoxflow (DSC/CdS(s)|VO2+,VO2+||V3+,V2+|Carbon Felt(s),E0=1.2 VNHE); in this configuration, theobserved photocurrent was 1 mA cm2.Given the acidic nature of the electrolytes (pHE0), thephotoanodes are still limited by their long-term stability. Toimprove further the performance of the proposed solar-RFBsystem, the CdS/CdSe junction should be further optimizedto produce more reproducible photoelectrodes displayinghigher photopotentials, currents and stability. Anotheroption is reduced graphene oxide, that have been provenuseful in minimizing CdS photocorrosion[53]. It is antici-pated that new approaches will be proposed and photo-electrodes able to delivery higher current densities andphotopotentials will be soon available. For example, organicalkaline electrolytes are currently being tested that allowthe use of stable semiconductors such as hematite

Unbiased solar energy storage: Photoelectrochemical redox flow battery. Available from: https://www.researchgate.net/publication/295539790_Unbiased_solar_energy_storage_Photoelectrochemical_redox_flow_battery [accessed May 01 2018].


A solar rechargeable redox flow cell
Abstract
The present invention relates to a solar rechargeable redox flow cell, a method for storing solar energy by chemicals conversion through the solar rechargeable redox flow cell, an electrochemical system comprising the solar rechargeable redox flow cell and a method of operating the electrochemical system. The invention allows for direct conversion of sunlight into chemicals production that can be stored and used as fuel in a redox flow battery.

https://patents.google.com/patent/WO2015120858A1


(noboxes) #149

I am looking forwards to a few years of testing this tech in a power company situation.


(bill mapezzi) #150

image readjust size of the three pods and connect them with vacuum tubes like drive up bank tellers have (so you can lay down flat and be sent across to the other pod. Make all the pods aerodynamic and the hull like an USS Albacore submarine. Three foil struts would give roll stability (dynamic) and rudder on the forward strut (also gives roll stability with symmetric foil shape. The two making a “V” in the rear would be asymmetric. Small Waterplane Area Monohull…

Or if you don’t want three pods…just one with the same three struts. All the accommodation under the panels…


(Marc Hawk) #151

less then 1/10 the cost, Nova Luxe!. affordable for your average wealthy person! is the tagline i use. I see the way the solar panels are on tracks that spread out. Interesting.