What's so Special about this Battery?
What's so special about this pesky Firefly Oasis battery that I'm tripping over everywhere I go?
The word seems to be out about the Firefly Oasis battery. So much so, in fact, that we seem incapable of keeping them in stock, and the manufacturer is so swamped that they can’t produce enough of them!
What is it about this battery that has stirred up so much interest? Maybe it has the same sort of allure that the Ford Model T did back in the day. With a choice of just one size, it can be ordered in any color as long as it’s a rather fetching green and blue, something that wouldn’t look out of place on the mantelpiece at Christmas.
Or maybe some folk are keeping them as pets, showing them off to fellow boaters in between feeding them freshly charged volts and cleaning up their discharge. No, there must be more to it ….
It’s a Group 31 AGM battery - Nothing ground-breaking there. It’s a VRLA (Valve Regulated Lead Acid), AGM (Absorbed Glass Mat), PSOC (Partial State Of Charge) battery, for all you AL’s (acronym lovers) out there. It’s a nominal 12 volt battery containing lead and acid and is no lightweight, weighing in at 75 pounds. It has comparable capacity to other Group 31 batteries and has similar charging requirements. No super-acidic acid; no extra heavy lead; no kryptonite or unobtainium. Pretty boring so far, so what’s the big deal?
10 Myth Busters - Solar Panels on Boats
I've just come across yet another sailing magazine article giving inaccurate and misleading information on solar power for boats. (Why don't they bother to do some research and ask the real experts?) So here is a list of ten myths and busts in an effort to set the record straight.
MYTH 1 - Glass solar panels with aluminum frames are the most efficient
BUST - No, no, no! The type of cell determines how efficient a solar panel is, not how it is constructed. Coastal offers three types of panels all made with the highest available efficiency SunPower® cells:
1) aluminum-framed glass panels,
2) razor -thin walk-on panels, and
3) flexible panels for installation in canvas areas like biminis.
All three types enjoy the same high efficiency because they all use the same cells with 22.5% efficiency. Glass panels are more common and less expensive, but not necessarily more efficient.
MYTH 2 - You can't walk on solar panels.
Air Cooled or Water Cooled?
Which marine refrigeration system is better when cruising in warm waters: air cooled, pumped-water cooled, or Keel Cooled?
A well designed and fabricated air cooled refrigeration system, like the Frigoboat Capri 50, should be able to maintain refrigerator and freezer temperatures in the tropics if the application, installation, and operation are all within the manufacturers' guidelines.
But in tropical/Caribbean conditions, air cooling will be 25% to 35% less efficient than water cooling. As a result, the overall power consumption of an air cooled system will be considerably higher than for a pumped-water cooled system, and very much higher than for a Keel Cooled system.
Many serious cruisers these days install hybrid Air-plus-Keel Cooled systems, where the air cooling is only used when the boat is hauled for any reason. For a new installation, this could be a Frigoboat Capri 50 installed together with a Keel Cooler, with a switch installed in the fan circuit of the Capri 50. Existing Frigoboat Keel Cooled systems can be easily converted to an Air-plus-Keel Cooled system by installing an Air Add-On condenser. This is accomplished with the use of just basic tools, and without any adjustment to the refrigerant charge.
If your boat is aluminum, then due to corrosion considerations that prohibit the installation of a Keel Cooler, you would be best served by installing a pump-water cooled system like the Frigoboat W50. That, together with the Air Add-On air-only condenser for use when hauled out, will provide the same efficiency as a Keel Cooled system, although the added current draw from the water pump will negate some of the power savings normally experienced over an air cooled system.