Will you go for solar (photovoltaic cells) on boat?

[PVboat]

Dear boat owners/users, I am doing research on the development of markets of solar (PV – photovoltaic) based boats . I would appreciate very much to know your opinion on use of electricity from PV cells on boat. This is a link to the questionnaire: http://www.questionpro.com/akira/TakeSurvey?id=459150
Thank you very much in advance for your interest! You might be interested to have a look at the ‘Shot overview on possible use of PVs in boats’ before answering questions. Check it at http://sunergy.thrijswijk.nl/solarboat/. I will publish the results form this survey at this page.

[FAST FRED]

When the decimal point in the purchase price moves 2 places solar will have its place.

Right now we put solar to its best use 75W Shell with a Trace C12 regulator keeps the batterys up on our boat at a mooring.

With a cheap $200 ,1750 W inverter we can use power tools ect , and the boat is always 100% charged.
This helps the battery life a lot , 5+ years out of cheapo 8D starting batts seems fine.

Solar is great , but not yet (if ever) for propulsion on a serious boat.

FAST FRED

[tom28571]

Fred,

I think your acessment is a bit too pessimistic. When there is room for them, as on top of a powerboat cabin, solar cells can do quite a bit more than that. 200 watts works well enough to run an Adler refrigerator/freezer and keep batteries up with engine running only enough for propulsion. It may not do more than that, but it is great to not have the noise, fuel or maintenance to deal with. Many sailboats of my knowledge make long ocean voyages using only solar for charging batteries if they give up the refrigerator.

You are certainly right in saying that solar is a long way from being practical as a propulsion source. However, should there be a magitude leap in efficiency of insolation to amperage conversion, solar will surely be in the game for real. If I remember correctly, about 6KW/day/sq M of solar energy falls on my lot each day in June. Harness this and you can cut your ties to the power grid.

[Wellydeckhand]

Flexible solar cell should be able to be incorperate into sail mast and part of sail and become a ready and significant source of power...... In consider you can almost cover the whole deck with this stuff.....

[FAST FRED]

AT $10.00 a watt its use will be very limited forever.

When solar is $1.00 a watt , it MAY be worthwhile .


Get the PV industry to bring the cost to 10c a watt , and the mid east will return to a third world sewer.

FAST FRED

[marshmat]

Solar power certainly has a lot of potential; I know Fred sounds pessimistic but he's right that the cost is the big obstacle right now.
Let's look at solar PV against some other technologies (approximate capital cost, ie. initial construction/installation):
Solar PV, spacecraft grade (22-26% eff): $50-$100/watt
Solar PV, home grade (12-18% eff): $5-$10/watt
Solar PV, home grade, mass production 5 years from now: Probably $2-$8/watt
Nuclear fission: $2-$5/watt, plus maintenance
Coal and gas: $0.50-$2/watt, plus maintenance
Estimates are ballpark figures but you get the idea. By the time you factor in the various subsidies, fuel costs, maintenance etc. of 'conventional' power sources, solar PV starts to look a bit more feasible. Especially if you wait five years, when a whole lot of new technologies currently in the lab are expected to be in mass production. $0.10 a watt would be wonderful, yes, but even at $2 a watt it will be cheaper for a lot of situations to generate power locally from solar and wind, than to tie into the grid.

[SeaSpark]

Nuclear fission: $2-$5/watt, plus maintenance
Coal and gas: $0.50-$2/watt, plus maintenance

Nulear power on yachts?
Coal and gas generators are also hard to find for use on pleasure boats.

It would be nice to find some figures on price per Watt for marine generator sets in sizes usually found on yachts. My estimate is that solar power will come out as a serious alternative when you compare these figures.

Genset faillure is common practice on cruisers, bet solar cells are more reliable. Anyway they make you less dependent on shore, extend you cruising range, something that most cruisers want.

[tom28571]

The cost per watt is important but the cost and bother of fuel, noise, maintenance and weight is not being given proper attention. The life of a solar panel is better than any alternative on a boat that I know of. 20 years is typical. Any genset in constant use approach that without a series of major overhauls? 50 watt rigid panels are available for $7 to $8 per watt up front cost for the life of the unit. Up front cost is just the start of the bill for the alternatives on a small boat.

[FAST FRED]

Nuclear fission: $2-$5/watt, plus maintenance
Coal and gas: $0.50-$2/watt, plus maintenance


Perhaps , but the cost of these commercial power plants is provided by investors , and tax subsadies such as deprecation.

Most Nuke power SELLS for about 3c and the other gas & coal go for 5c or 6c , to a power company for distribution, and 12c or so to home owners.

When we can create our own power for what we now pay for power , it will make sense , perhaps , to do our own capatalization of the supply.

Till then retail power purchase makes far more dollars and cents , sense.

Unless you have a very very special need.

FAST FRED

[tom28571]

True enough Fred, but I thought we were talking about boats.

[FAST FRED]

but I thought we were talking about boats.


On most boats the biggest long term energy user is the refrigeration/freezer.

Solar can work on a boat for refrigeration , but within severe limits.

At leasat 200W of generating panels seems to be necessary for eith a small OTS unit (Tundra), or for a larger Quality insulated custom box reefer.

200W is a large area to be unshaded and safe from damage (foot trafic ) .

Then the system will require a mechanical backup for those rainy weeks.

This requires a large (at least 50 hours) batt set , some type of noisemaker to create power , usually a large alternator with special 3 or 4 stage voltage regulation.

A big price as a backup , although certainly the vessel when static will be glad of the DC ,for consumer toys.

If the noisemaker is fitted with a good sized mechanical pump (cast iron auto air cond compressor) and good sized eutetic plates are installed in a well insulated box , the performance between recools will be better than the electric unit.

Best of all , the eutetic plates and mechanical refrigeration can easily be home brewed, and repaired most anywhere.
Not so for the computer controlled DC compressors , necessary for efficent DC refrigeration.

So where you go cruising might be MORE important than the avilibility of delicate overpriced solar cells.



FAST FRED

[tom28571]

Originally Posted by FAST FRED

but I thought we were talking about boats.


On most boats the biggest long term energy user is the refrigeration/freezer.

Solar can work on a boat for refrigeration , but within severe limits.

At leasat 200W of generating panels seems to be necessary for eith a small OTS unit (Tundra), or for a larger Quality insulated custom box reefer.

200W is a large area to be unshaded and safe from damage (foot trafic ) .

Then the system will require a mechanical backup for those rainy weeks.

This requires a large (at least 50 hours) batt set , some type of noisemaker to create power , usually a large alternator with special 3 or 4 stage voltage regulation.

A big price as a backup , although certainly the vessel when static will be glad of the DC ,for consumer toys.

If the noisemaker is fitted with a good sized mechanical pump (cast iron auto air cond compressor) and good sized eutetic plates are installed in a well insulated box , the performance between recools will be better than the electric unit.

Best of all , the eutetic plates and mechanical refrigeration can easily be home brewed, and repaired most anywhere.
Not so for the computer controlled DC compressors , necessary for efficent DC refrigeration.

So where you go cruising might be MORE important than the avilibility of delicate overpriced solar cells.FAST FRED

Fred,

I don't want to get into an argument. The situation I described is from experience. The boat in question cruised the east coast from Lake Ontario to southern Florida for over a year. Two 50W solar panels on the cabin roof, Adler mechanical refrigeration and the usual other electrics. It was enough power but no big surplus. Boat power was a 50hp Merc, so no big alternator there - about 13 amps, I think.

Solar power systems must be chosen for the job and aren't always adequate for many applications. When they can handle the load, like on an outboard powered cruiser, I much prefer them over a genset. Solar is not overpriced. It is priced to meet competition and make a profit. Its not always competitive with on board generation but often is. Unlike gensets, it will get less expensive with time and lasts longer.

For me, freedom from noise, fuel bother and cost (did I mention fuel cost) and maintenance is worth a lot of bucks in the cost equation.

[Wellydeckhand]

Pls see those Swiss design electric boat........ cool and practicle used of solar power......... only if we can use it fully free electric on a sizable full length yacths

[FAST FRED]

The biggest problem with electric , or solar has always been the batterys, and the long dance needed to recharge them properly.

Popular Science claims a new breed of Lithium Ion batts can be broulft from 0 to 80% in ONE MINUET!

They are being developed for I-Pods and small Cell phones , but perhaps they will eventually be scaleable to 1000A

Of course I'm still waiting for that Popular Science personal air car in my garage ,coming soon, in 1955!

When the storage issue is resolved , the world will change!!

FAST FRED

[tom28571]

You are certainly right about the power storage issue. At this point it is still very hard to beat the old lead-acid battery. When I got out of college nearly fifty years ago, fuel cells and maglev trains were just around the corner. It has proven to be a big corner.