Marina power

[Hkalan]

Hello,

Been living on my boat for 2 years at this marina. Summer is in full heat now. The price per kWh has just gone up to 0.25 USD per kWh.

Although we have all the windows and doors open on the low humidity days. We installed a split unit residential air conditioner in the saloon and master cabin, as the occasional jelly fish, or plastic bag would find its way into the strainer for the cruisAir units, and shut down a few times a week in the marina shelter. Got tired of cleaning out the Jelly Fish.

My question is how those on live aboard keep their AC consumption at a acceptable level. Last month my bill said I used 1,232 kWh. All lighting is LED off the house bank. We have the inverter that is powering the fridge, TV, computers. The 1,200w solar panels top off the 1,200Ah house bank during the day. We cook with LPG, and hot water via tankless LPG water heater.

I almost feel that 2 boats would use 1,232 kWh per month.

Alan

[transmitterdan]

It doesn't sound too far off. Residential units are not efficient compared to water cooled units unless water is above 75F. Your monthly usage is equivalent to about 140A continuously from 12V batteries. Solar and LED are not a drop in the ocean by comparison. Try your water cooled system and your usage should go down. Run each one for 10 hours and record the meter reading before and after each test to see which is more efficient.

[colemj]

Here in the Rio Dulce Guatemala, we are paying 0.46 USD per kWh. We run a single 16,000 BTU unit controlled at 78F on a 40' catamaran and are using 300kWH/month.

Your boat is larger, so would take more cooling, but your usage does sound high regardless. I personally monitor the electrical meter and track our usage because we have had marinas in the past simply make up outrageous numbers. Have even taken time dated photos to use as evidence.

Full canvas tarps set over the boat helps reduce the heat load dramatically. Maybe close to halving it.

Mark

[valhalla360]

Assuming 50% duty cycle, that translates to around 30amps @ 120v (not sure hong kong voltage).

Assuming that is a 70' boat in your info, that sounds pretty reasonable. We pull about 10 amps in out 34'.

I wouldn't get too excited about marine units. We just went with an air cooled unit and it draws almost the same as the water cooled marine unit it replaced with the same BTU rating.

[Hkalan]

Hello,

On the 70 foot Grand Harbour (Ruby), as well as the 50 ft Chinese Teak vessel we are restoring, have the exact same 2 units. One in the Saloon, and One in the Master Cabin.

We have 230v 50Hz AC power in Hong Kong (220v 50Hz appliances).

Attached is the label on the side of the evaporator unit of the split system on both vessels.

I am installing a kWh meter in the main AC panel on the Chinese Teak vessel so I can accurately monitor the power consumption !!!

Thanks,

Alan

[SecondBase]

+1

Maybe close to halving it.

http://cooltarp.com/

[Stu Jackson]

The AC fridge would seem to contribute a lot, too.

[SecondBase]

12v cabin fans bring perhaps another 10 degrees of air temp "down" into the comfort zone. Fans use less juice than AC.

1-2 cabin fans for every 10 feet of hull does the trick.

The fans should be run 24x7 for as long as you own your boat for more than one reason.