On board power

[Sandyhollow]

In my experience take the time to do an accurate power consumption worksheet. Understand 110 ac power can be a burden, switch as much as possible to 12v. Then try to figure any future upgrades you are interested in. Calculate the size of the array and then begin to search for charge controllers that can handle the array. Then research battery type and size. Proper planning on the front end will greatly enhance the effectiveness of the entire system. My FB page 'Sailing Faith' has a few posts on how we got it done.

[a64pilot]

Forget the drier, if it's the type of drier that generates heat, our washer just spins, but gets clothes so that when hung up, they dry quickly.

I'm going to throw a curve ball at you and go against conventional wisdom. Rather than trying to determine down to the amp your current use and based on that sizing your Solar and bank, I'm going to say put on as much as you can fit and or afford, same with the battery bank.
Worst case, you end up with excess, what does that mean? Well a bank that is cycled shallower will last up to years longer, and excess Solar will mean you get closer to that 100% charged every day goal, and will mean you have enough in winter and on cloudy days, where if you are sized just right, you won't.


It is exactly like money, if you have just enough then your all the time having to watch the budget to make sure you don't go in the red, if you want to buy something, you have to balance the check book and determine if you can make cuts somewhere else to get by.
However if you have a little excess money, you don't have to watch the bank balance, and if you want something, just buy it, no stress.
Same with electricity, if you decide to splurge a little and make some ice for drinks and watch a movie, go ahead and splurge, if your on an energy budget, then you have to cut corners somewhere else to pay for it

[Teknishn]

Originally Posted by Sandyhollow

In my experience take the time to do an accurate power consumption worksheet. Understand 110 ac power can be a burden, switch as much as possible to 12v. Then try to figure any future upgrades you are interested in. Calculate the size of the array and then begin to search for charge controllers that can handle the array. Then research battery type and size. Proper planning on the front end will greatly enhance the effectiveness of the entire system. My FB page 'Sailing Faith' has a few posts on how we got it done.

I totally agree with this. Have done the same for my boat in the planning stages for adding solar power.

For the OP, and anyone that can use it, I'm attaching a basic 12-VDC Power Consumption Calculator in Excel. Please be advised that I have not protected this file or locked cells in order for it to be modified to suit your specific equipment/systems (Hope you're good with Excel as my Virtual Basic is pretty weak....OK, it sucks). Warning!: ONLY modify the equipment/system nomenclature (Change the name) and ONLY clear entries in the "Pink" cells. Clearing any other cells will delete the formulas associated with that field, and possibly others. Intentionally left it open so that others may use and modify it to suit their boat's needs.

To the OP, you need to know the power consumption of each and every thing on your boat in order to properly manage your power usage, plan for upgrades, additional amenities and to figure out the additional power requirements needed. Hope this helps and good luck!

Edit: The attached file didn't attach apparently...trying again

[Teknishn]

Grrr....Tells me that a sxls file is an invalid upload. Sorry ya'll

[john61ct]

"Save as" an older flavor of Excel

[carstenb]

Look - for those guys telling you can't do this - again our boat is 40 feet, we have two 335 watt sunpower panels mounted on our targa bar. They provide all the juice we need and charge our 600 AH AGM batteries completely full without any problems

We have a 250 liter fridge with a samll freezer, an ice cube machine that takes 90 watts at 220 volts, we run our hot water heater (1200 watts heating 40 liters of water) twice per day. All or lights are LED, we have a stereo and use it, we have a TV, but almost never use it (12 volt tv). We do not worry about electricity, we just use it - we also ahve electric water system (faucets) and we both shwer twice a day here in the caribbean. We ahve a watermaker (8Amp per hour) that we run for 3-4 hours every third day or so.

The only time we ahve to be careful re: juice is when we passage sail if we don't bother to rig the windvane - then we're using the autopilot and then we're really using juice.

But if the sun shines then the panels recharge our batteries even though we have run then down by 150-180 AH . Our 600 AH AGM batteries handle all this without problems

So if you work at it you can find room for this on a 37 footer.

[john61ct]

Horses for courses, your consumption is relatively modest.

Running huge loads like A/C and clothes driers would require 5-10 times the panels output.

If he wants these latter, best to run a nice genset to feed them, and then maybe have some excess to fast-charge and not need so many panels.

[StuM]

Originally Posted by carstenb

We ahve a watermaker (8Amp per hour) that we run for 3-4 hours every third day or so.

You mention items running at 12V and 220V . You don't need to specify voltage if you tell us the wattage, but one place where it makes a difference, you don't specify.

Is your watermaker 8 Amps (not "per hour"!!) at 12V or 220V?

[cayennita]

In my 51' sailboat, I installed a 8.5 kw gen set. Microwave, coffee maker, toaster oven. 400 gl/ day watermaker, 120 v refrigerator/freezer system. 2/16000BTU's A/C's. 4 6 volts Trojans. Separate starter batteries. The Inverter/charger will run all but the A/C's. actually, I never tried it. When at anchor, I run the gen set twice a day. In the morning and at night one hour each. Always had ice and hot water. I don't like roll bars with all kind of things hanging all over the place. If we are leaving the boat, and not at a marina, for an extended period then we remove any thing that can spoil and give it away. Did this for 15 years. Age made us move to a condo and day sail a Catalina 30.

[carstenb]

Originally Posted by StuM

You mention items running at 12V and 220V . You don't need to specify voltage if you tell us the wattage, but one place where it makes a difference, you don't specify.

Is your watermaker 8 Amps (not "per hour"!!) at 12V or 220V?

Stu

As usual, you electrical knowledge is far greater than mine and I tip my hat in respect

The watermaker is a spectra 200T, makes 30 liters per hour and uses 8 amps at. 12V dc. Spectra says it uses 8 amps - according to my measurements it really uses about 5.5 amps.

Nevertheless - our 2 335 watt panels provide all the juice we need - but admittedly we don't have, and don't feel the need for AC. A washing machine might be nice but we don't have a problem washing our clothes by hand - i mean we got lots of time and here in the tropics we don't wear many clothes anyway

[PacificGreen]

I like 48v for power distribution. Things just run better. Loose all the 12v appliances and propane you can. A 20kwh lithium battery pack 16 400 ah cells in series is plenty - you can even propel the boat with that amount. If you have sails you might want to consider ditching them as well. Big generator or diesel engines sell.

Power Producers:

2 48v Lestronic II 48v chargers (Provide 30amps)
2160 Watts Flexible Solar (120lbs installed produce over 1000W)
2 AlphaGen DCX3000 36/48v Generators (50amps <52.5v load bearing)

Power Distiubution:

2 Cotek 3000w 48v Inverters
1 Max Burton 120v to 12v converter (15amps 200w)

Power Consumers:

2 Induction Cooktops (20amps on lvl2 setting)
1 Toaster Oven (35 amps but great feature - big consumer)
2 Quick BH16 Quick Nautica Boilers (50amps hot 1/2hr)
1 Incinolet Electric head (42 amps burn 18amps blower)
1 Hair Portable Washing Machine (22 amps)
1 Electric infrared heaters (28 amps max - Nights 10 amps)
1 Ceramic Square heater (25 amps)
2 Dehumidifiers (3 amps each if that)
1 3.2cu ft fridge (5 amps)
12v Electronics (Radar, VHF, Chartplotter, Nav lights - 4amps)
2 Laptops (2 amps)
2 Ray Electric Outboards 48v (0-160 amps - 20-30amps 4 knots 100+6.7)

Boat load can be reduced to a miserly 5amps when cruising. Displacement 5600 lbs on the travel lift loaded wet tools and all fully provisioned. Most amp usage observed while on hard or dockside plugged into extension cord for chargers. Catamaran is quite capable of long extended journeys of unlimited duration with or without shore power.

This cat has big wide displacement hulls that are still quite efficient to push. I only wish I did this all this on a cat with nice sleek hulls.

[PacificGreen]

Keep the 12v appliances as they are at least DC to DC.

[sealife1]

I would suggest consulting a solar expert as there are so many variables. Where are you sailing? What is the weather? How often are things running simultaneously? Lithium batteries are the way to go but not the ones made in China. This is an area you definitely want quality and that isn't cheap. I know a woman in St Petersburg, Florida who is an expert in these things her name is Nancy Frainetti. She is very nice and very knowledgeable. You could probably consult with her for a few hundred dollars and gain so much more then that in education and advice. Her website is www.theelectricmarina.com. I am going to actually replace my Diesel engine with electric and she is going to be doing the switch. Worth an email to her.