Jumping Jack Flash - It's a Gas, Gas, Gas
There has long been a debate about air cooling versus water cooling for marine refrigeration systems. Water cooling has traditionally been generally accepted to be between 25% and 35% more efficient in warm/hot ambient conditions, but some of that efficiency gain has to be offset by the energy required to run a water pump.
The Frigoboat Keel Cooled system is water cooled and does a fantastic job without the need for a fan or a pump. That will be mentioned later, but the following compares air cooled systems to traditional water cooled systems using sea water with a pump.
Many boaters these days seem to be opting for air cooled refrigeration systems even though they’re heading south into hot climates, and despite the notion that air cooled is inherently less efficient than water cooled. Why is that?
What a Trucking Nightmare
We have several house rules at Coastal Climate Control. There are the typical ones such as the sign in the warehouse toilet saying “Gentlemen please lower seat when finished”, and then there are unwritten words of wisdom like; ”If you have it, flaunt it”. Personally I’m a bit lacking in flauntable assets, but Coastal sells some of the best specialized marine equipment available, and we flaunt it whenever possible. In fact, next week we will be in very flaunty mood at the Annapolis Spring Sailboat Show April 20 thru 22, so if you’re in town come on by and see what’s new.
Another unwritten house rule is: “If we don’t have it, we can’t sell it”. It seems obvious I know, but keeping adequate stock of popular items is becoming a bit of a problem these days, especially for products that we import. We strive to be good girls and boys and pay our bills on time and plan way ahead in order to anticipate shipping delays, but we still often get caught out, and increasingly so these days. There are three main areas that we have no control over:
But Weight, there's Less!
So Elon Musk has parked his Tesla in the Milky Way or wherever. Just imagine having the capability and resources to do that, and the mind boggles at the thought of what else you could dispose of up there in the big blue yonder. I presume that he removed the battery before take-off, because those things are heavy.
Yes, I know they are Lithium Ion (LI) batteries, but those are not as light as some imagine. I know this from when I drive my Chevy Volt to my office in Tesla Drive (a bit ironic don’t you think) and feel how solid and sure-footed it is on the highway. That’s because it weighs about 800 pounds more than a similarly sized Chevy Cruze due to the hefty battery pack. But thanks to that 17kw lump, I have sizzling, silent acceleration and decent range in a very stable platform.
Talk is that there’s soon to be an Electric GT motor racing series featuring a modified Tesla. This will no doubt have phenomenal out-of-the-box performance, but weighs in at about 200 pounds more than my road-going Volt, and where less weight = more speed (i.e. on the race track) that means a lot of lithium to be grappling with lurching around the bendy bits.
I started tinkering with LI batteries six years ago, and even made my own 100 amp/hr pack from bits and bobs I bought online. I did it primarily to investigate whether that might be a viable alternative to the few expensive and complex marine LI systems available back then, but soon realized that the safety aspect was paramount.
Those specialized marine LI systems featured external Battery Management Systems (BMS) that could cut loads and/or charging devices if anything got slightly out of whack, and when you’re in the middle of an ocean that’s a pretty important feature. Most of the online offerings I came across were for auto use, where it’s assumed that if something goes wrong you can pull over to side of the road, hop out, and run away. Not so good for a yacht where the closest land may be a just mile away, but happens to be straight down, on the ocean floor.