Solar power Basics

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  • D.I.M.1
    D.I.M.1 Solar Expert Posts: 59 ✭✭✭✭
    Re: Solar power Basics

    LOL but anyway, that was just one of those parameters I wanted to ask, I'll ask my BD forum for more constraints concerning the size of the battery.
  • D.I.M.1
    D.I.M.1 Solar Expert Posts: 59 ✭✭✭✭
    Re: Solar power Basics

    I come bearing the good the bad and the fairly depressing.
    First technology isn't so far along to make my project viable, or at least that's what ten forum posters, an engineer and my gut have told me. Why? since batteries suck.
    The energy density of gasoline or combustible liquid fuel sources are too great that our current level of batteries aren't even close to effective as them, which is why we don't have battery power cars and what not.
    The good news is I have redefined my goals, the even better news is that my idea based on a prototyping engineer's opinion seems appealing and will work out in the markets. My idea is to use renewable energy to power the auxiliary systems on boats and if there is a problem with the fuel or in case of emergencies, the auxiliary battery could be used to propel the boat at a slow rate of speed indefinitely since there is always wind or sun on the ocean. Storms= winds, No storms= sun, cloudy= you're screwed.
    The depressing news is that I have to write a knowledge based paper and I'm terrible a t writing, but that shouldn't concern any of you guys I just ranting in this third or fourth paragraph ignore it.
    DIM
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Solar power Basics
    D.I.M.1 wrote: »
    .... My idea is to use renewable energy to power the auxiliary systems on boats and if there is a problem with the fuel or in case of emergencies, the auxiliary battery could be used to propel the boat at a slow rate of speed indefinitely since there is always wind or sun on the ocean. Storms= winds, No storms= sun, cloudy= you're screwed.

    Say you have 2KW of alternative power at hand - sun, wind, whale blubber.

    as an exercise, what speed can that propel the vessel, at what cost of initial investment, and travel time?

    Is it better to have a good radio and call for help, or put-put for 3 weeks with no food?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Solar power Basics

    It's not just batteries that suck: solar panels are at best 18% efficient. Imagine the results if that number were closer to 100% - like newer inverters that run 93%. Wind turbines ... another efficiency nightmare.

    There is the whole energy problem in a nutshell: inefficiency. The gird suffers from losses in transmission (up to 50%!), generators turn more fuel into heat than electricity, and then the end user wastes 75% through lack of insulation or low PF equipment or sloppy management.

    Live off grid for a while; learn about waste! I go from my All-Electric 'winter' house in the Lower Mainland where BC Hydro charges 7 cents per kilowatt/hour to my cabin in the woods which has so far cost around $16/kW/hr (it'll come down). Manage to live much the same, switching from 48 kW service to 3.6 kW solar.

    A big part of it is using the right type of energy for the job, too.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Solar power Basics

    Marc,

    Not to pick nits,, but IMHO, efficiency of Pv solar panels is not really an issue, but rather the cost of said same. Efficiency of Pv is really only a concern if there is limited space to put panels, and in most cases space isn't the issue, dollars are.

    For example if a 15% ef panel cost $3/watt and a 5% ef panel were $.50/watt, (all else being equal) then the latter would be the better deal. What we need is not really the ability to make panels that convert sun to electricity more efficiently (although that would be nice) but rather be able to manufacture Pv at a net/net lower price.

    I do agree however that inefficiencies are rife within the system. The search for energy efficiency begins "at home" however. As you well know, you can live quite well in your bush cabin on way less power than you can in your city home. The key is to figure out how to make the city home more efficient. (metaphorically at least!)

    The reality is when we are in town, we use energy like a drunken sailor sort of. TV's left on, lights where we don't need them, long hot baths etc, etc, etc. The reason is that is because it is too easy!

    Tony
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Solar power Basics

    Tony;

    No argument! But the panel efficiency is an issue with the OP's idea, as he needs to produce as much power per square meter as possible due to the size limitations inherent in a boat design. Imagine having a panel the same size as a 175 Watt unit but instead putting out 900 Watts!

    Yes, at first it would probably cost $1 million per panel. But prices have been coming down and efficiencies have been going up. Let's hope the trend continues. Like with computers. :D

    You're right about usage; we waste as individuals and even more so as a society.

    'Motel' Marc
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Solar power Basics

    I don't know what they cost now, but you can get near 30+% solar panels for $300-$400 per watt range (back in 2002-space rated).

    Even if you assume satellite rated makes everything 10x as expensive--they still would be over $30 per watt...

    Regarding using cheaper, less efficient panels; if you assume that mounting framework costs ~$1 per watt for a crystalline panel ($3.00 per watt + $1 mounting = $4 per watt). Assume they are (to make things worst case and easy to use numbers) 15% efficient...

    Vs a 5% efficient amorphous panel at $0.50 per watt + 3x$1=$3 per watt for frame work = $3.50 per watt hardware (3x more panels to mount because 1/3 the efficiency)...

    $3.50 a watt hardware costs for hardware with "cheap" $0.50 per watt panel vs $4.00 a watt hardware for the expensive crystalline $3 per watt panel.

    Add the extra labor to install and wire with 3x the number/square footage of $0.50 per watt solar panels panels... The "cheap panels" do not really reduce the costs by any appreciable amount (or may even increase overall system costs).

    Of course--I am just using past rules of thumbs... Get a quote from a reputable installer/retailer for real numbers based on your requirements.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Solar power Basics

    Even with 100% efficient cells, that would be about 0.7HP per square meter of area at solar noon. Basic math will show that you would need huge areas to move a vessel, so the point is moot. There isn't the energy available in the irradiance from the Sun to replace a fossil fuel based method of transport in real-time
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Solar power Basics

    And, without batteries, you would only be able to move the ship on solar power for 6 hours per day or less (depending on season, weather, and location).

    If you want to move the ship 24 hours per day with solar power, you need to gather at least 4x as much energy during the 6 hours to give you 24 hour motive power (excluding losses from conversion and batteries, etc.). So, now you are looking at 4-8x the area of solar panels/wind turbines/etc. for your 24 hour power vs just during daylight power.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Solar power Basics

    On the contrary, humans have been moving ships via solar power for millenium! Truth be told sailing ships at the height if their technology moved amazing loads with (relatively) amazing speeds. What was the Clipper ship speed record from England to NY, 12 days 6 hours? Not too bad for free "solar" energy. Question is with modern design and technology how much better could it be done with sailing ships? Not only can yo do it, it is a pretty reliable and predictable power source.

    Tony
  • dwh
    dwh Solar Expert Posts: 1,341 ✭✭✭
    Re: Solar power Basics

    And no one has yet mentioned a head wind. In put-put RE mode, even if you could get the boat moving, it would probably move backwards if there was any head wind.

    Run out of gas? Try the radio. Radio doesn't work? Fire up the EPIRB and wait.


    DIM,

    There are plenty of boats out there using renewable energy. But it's mostly on the same scale as RVs - a couple of PV panels, a couple of batteries and that's it. Mostly enough to run the radio or flush the head. Maybe keep the fridge going for a couple days.

    To stick enough PV modules on a vessel to do any good, would require a LOT of square footage of flat space to mount them. Not likely to happen on a ship. Now, a barge might be a different story. There might be a few types that would be perfect to stick a large PV array on:

    http://www.maritimesales.com/Barges%20for%20sale.htm
  • westcoastslider
    westcoastslider Registered Users Posts: 20
    Re: Solar power Basics

    The only realistic way of powering a large vessel with renewable energy is Waste Vegetable Oil!
    Many people have been successfully running there diesel powered vehicles on it for years. I wouldn't be surprised if there where a few commercial fishermen doing it too...
  • D.I.M.1
    D.I.M.1 Solar Expert Posts: 59 ✭✭✭✭
    Re: Solar power Basics

    You're right sadly I have to redefine my goals.
    And I have, so I'll get back to you all when its tweaked.
    The really high blood sugared
    DIM
    HAHAHAHalloween