I thought long and hard and then pulled the trigger on one of these + two
batteries. It arrived this week and I used it for the first time today.
https://www.zerobreeze.com/products/zero-breeze-mark-2
It seems everyone who wants
air conditioning on their
boat focuses on adding more
generator, more
solar, more
batteries. I decided to go the other way, focus on an a/c unit that uses as little
power as possible. As far as I can find, Zero Breeze is the only
battery powered air conditioner there is. Not a swamp cooler, but a true a/c unit. It's not
cheap, although still significantly cheaper than installing a normal
marine a/c unit. It was designed for people going camping but I figured it would
work on boats. It was easy to set up and use, even without reading the instructions first.
It works as advertised, but there are strengths and weaknesses. It was designed for a tent or a
cabin. It won't cool down a large yacht. My
boat is 36' and it handles that alright, but a
single cabin would be better. It was also bigger and heavier than I expected. The photos on their site show people carrying around while camping, but it weighs almost 30lbs together with
battery.
Unlike
marine a/c systems, it doesn't use a
water intake &
exhaust, instead it does it through the air. Which means you have to set it up for the
exhaust to go through one of your
portlights. That's a little awkward, and I'm still trying to find out the best place to place it on my boat. But the good news is that it comes with several foam templates that you can easily cut to fit a window. I attached a
photo of my first attempt setting it up, letting the
water drain into the sink (it comes with a little hose so you can drain it where you want). I could instead put the unit outside in the
cockpit and run a hose blowing cold air into the inside, but it would have to be protected from rain.
You can
plug it into 120v
shore power outlet, but if you want to
plug it into a 12v outlet, you need to buy a separate adapter for $99, which sucks. But then again it's a 24v system, so people who set up their boat on 24v might be able to rig it directly. On batteries, it's supposed to run from 3-5 hours. For me it ran about 3 hours on maximum cool setting. The batteries are expensive but substantial, and have USB
ports to charge other devices (24v 35Ah/840Wh)
One pleasant surprise is that it pulls moisture from the air so it drains the water out the back. In other words, it's also functions as a
low power water maker in humid environments. It made me about a coffee mug full of water per hour.
Pros:
- It quickly cools
- Easy to use
- It creates fresh water
- Runs very quietly
- The batteries are useful to charge other things
Cons:
- No heat, just a/c
- Works in a limited area
- Awkward to set up in a boat
- If you want to plug it into 12v you need to buy an adapter