Adding Solar and some Power Thoughts

We made the last major upgrade to the boat: we added a hoist for the dingy (a davits) which includes 2×400 watt solar panels on top. We travelled to ‘the guy’ for Amel arches (Emek Marine in Gocek, Turkey) and we are very happy with the result. Here is a picture:

It is a beautiful design that fits with the look of the boat. Lots of other arches are square looking pieces of stainless steel that are functional, but ugly. Very happy with this.

On Spruzzo we use roughly 3600 watts of power a day, or 3.6 kW. You might think that with 800 watts of solar I could make maybe 800 watts * 8 hours for 6400 watts of power……but I don’t think that will ever happen. Today (mid-September) we made 2600 watts of power. It was perfectly sunny all day, but we are in an area that is shaded after 4pm so maybe I’ll get a bit more in the future or in mid-summer.

In the bad old days ;-), before solar panels, to get power I would run the generator for 4 hours a day (2 hours in the morning, 1 in mid-afternoon and 1 at 8pm to fully charge the batteries for the night). 4 hours of our wonderful 3-cylinder diesel Onan generator uses about 8 litres of diesel, which costs about 12 euros. This means our cost per used kilo-watt from our generator is about 3.3 euros or C$5! Now compare this to Ontario….the cost per kwh is C$0.13! Such a difference! Note that I make sure the batteries are fully charged at least once per day. Lead-acid batteries like to be fully charged frequently.

Interestingly energy consumption on the boat is much less than at home. I found an electricity bill from last year and I roughly used 700 kw/month at home….on the boat I am using 108 kw/month.

Besides being expensive, I don’t like running the generator because it is noisy. It is nice to be on a quiet boat.

I expect now to run the generator for 1 hour in the morning and 1 hour at night or however long it takes to charge the batteries. Update: today I only needed 30 minutes at night to fully charge the batteries! Better than expected.

I expect to save 4 litres of diesel, or about 6 euros/day of cost. The cost of the entire solar system (panels plus charge controllers plus new chargers/inverters plus battery monitor) has a payback of 1000 days of use, but perhaps it is not fair to include the new chargers/inverters….if we exclude them the payback is a more reasonable 500 days which is about 2 years of cruising. Plus I’m helping reduce green-house gases!

The New System

This is what I installed:

2x Sunpower 400W panels

2x Victron 150/30 MPPT solar charge controllers

2x Victron Multiplex 24/3000/70 inverter/chargers

Victron Battery Monitor

The solar panels were new, but I replaced the existing 2000w inverter and the 2x existing battery chargers (I think they were 25w and 75w respectively). The 2 Victron Multiplex chargers/inverters work together so they can provide 140 amps of battery charging and up to 6000 watts of 220v power from the batteries. We also don’t need to turn on the inverter any longer, it is always on.

Previously we had to be careful with what we turned on with the 2000w inverter and not everything would work. For example, the espresso machine would not work off the inverter (as an aside, I bought a very expensive coffee grinder and a good semi-automatic espresso machine which combined makes great espresso!), the dishwasher would not run off the inverter, and no Air Conditioning units could run off the inverter (ed. note by V: I can actually hear 80% of liveaboards rolling their eyes at the “hardships” we had with the inverter not being able to run the espresso maker (1), the dish washer (!!) and the A/C (!!!) when most boats don’t have these things anyway…). Now we can run almost everything at once! This is a big upgrade for the boat. (During the boat survey, when the French boat surveyor looked at the cheap inverter we had on the boat he pointed to it and swung his chin in the air a bit and said in a french accent: “I would replace THAT”.)

The battery monitor and the solar charge controllers are all blue-tooth enabled and can be monitored and configured by a Victron app which is very cool. I assumed that the inverters/chargers would be the same but you need to buy a device to blue-tooth enable them…..which I didn’t know and didn’t do. Maybe I’ll do that over the winter.