Island Power

Steven Lake
Steven Lake Solar Expert Posts: 402 ✭✭
http://assets.amuniversal.com/91685e4046200132ab36005056a9545d

Ripley's had another one today. Apparently the island nation of Tokelau gets 100% of its energy from solar. WIN! :D

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,402 admin
    Re: Island Power

    Here is some more information:

    http://tokelau.org.nz/Solar+Project.html

    Note, they are also using generators powered by coconut oil (backup? Assist?).

    Not a small system:

    http://www.nzeco.govt.nz/news/21mar13
    The project involved the installation of 4,032 photovoltaic panels, 392 inverters and 1,344 batteries across the three atolls (Fakaofo, Nukunonu, and Atafu) in the South Pacific Ocean. The atolls have a total land area of 10km² and a population of approximately 1,500 people. Until recently diesel generators were burning around 200 litres of fuel daily on each atoll, meaning more than 2,000 barrels of diesel were used to generate electricity in Tokelau each year costing more than $1 million NZD.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Steven Lake
    Steven Lake Solar Expert Posts: 402 ✭✭
    Re: Island Power

    Wow. They were spending $1mil on power over a year with diesel and with the new solar system they're probably only spending $3 mil total for the solar system. So in about 3years they'll pay off the entire system and basically have free energy after that. Nice. :D On the upside, if they pay for the entire system in the first 3-5 years, baring repairs and other necessities, they could spend the next 17 years storing up the money to completely replace the system and pay cash. lol. And that counts periodical replacements of bad batteries, inverts, and other parts.

    The part that's kinda mind numbing to me is that it took about 2.5 panels per person of power, but less than 1 battery (how bloody big are these things!? O_0) and about 1 inverter per 4 people. That must be quite the system to setup and maintain. o.0;;
  • zoneblue
    zoneblue Solar Expert Posts: 1,220 ✭✭✭✭
    Re: Island Power

    Thats called following the new cost model. Batterys are expensive and short lived. Hence the less the better. They have coconut power for the shortfall.
    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,
    http://zoneblue.org/cms/page.php?view=off-grid-solar


  • Steven Lake
    Steven Lake Solar Expert Posts: 402 ✭✭
    Re: Island Power

    Yeah, I admit they're short lived, but a well maintained wet cell can get you 20 years easily. It just depends on how you manage it and maintain it. I've had wet cells last that long if not longer. Of course, you have to have someone who knows the technology. I only understand them because my dad about beat it into me as a kid. If I'd abused an old wet cell and let it die, my butt would have been smarting for well over a month. o_0;;
  • Ks Solar
    Ks Solar Solar Expert Posts: 47 ✭✭
    Re: Island Power

    I am ready for RE particularly solar to be cost effective with coal/diesel etc. This and other RSS feeds gives me hope. Any truth to something I read, a military wet cell found in an old plane crashed on the bottom of one of the great lakes was still viable after 60+ yrs.?
  • Steven Lake
    Steven Lake Solar Expert Posts: 402 ✭✭
    Re: Island Power

    KS Solar, yeah I heard something about that too, but I don't remember when. As for viability we've got old wet cells from when I was a kid still going strong, so I know if you take care of them they'll last a long time. And speaking of wet cell technology, there is one out there, I forget who makes it, that's got to be the ultimate wet cell ever. It's got the ultra thin plates like what's used in AGM, but it's a flooded battery and so far, at least from what I hear, it's got great energy density and reliability. I wish I could remember who made it, but the video showed them actually having to compress the plate pack just to make it fit in the box it was supposed to go into. lol. Now that's what I would call dense. But yes, batteries are the lynch pin of every system that's entirely off grid. That's why I'm always looking for any possible way to augment energy generation in some way to take maximum advantage of the energy that's brought in and its storage.

    One interesting technology I'm looking into is what one person locally called "switched full cycling". Basically it's two identical battery banks side by side that work back and forth in concert with each other on charging and discharge. Apparently the concept is that one is dedicated entirely to charging with zero discharge during the charge cycle meaning that after each discharge it's topped up to 100% before use. The other is then drained down to like 50-60% (or higher if the other bank completes its charge sooner than later) while the other bank is charging. So with that one there is no power incoming while it's being drawn out. Apparently the idea is to minimize the charge/discharge cycles the batteries have to go through. So rather than 365 days of up/down charge/discharge they go like two days up, two days down, or if usage is higher, one up, one down. It probably doesn't actually extend battery life but the idea seemed intriguing none the less as the concept sounds like it would work. At least in theory. ;)