As promised in other posts, after the crossing we looked at our power systems. The solar worked, but 22 years of data on cloud cover, and calculating the length of the day and the sun angle shows that in the Salish Sea in January on average you get only about 8% out of your solar panels on average. That’s not a lot, especially not as that is why you’re running ACs in reverse to heat, drawing an additional 30%.
During the design and construction of Vingilótë we made many decisions about what she would be when she grew up. We decided against a generator (more at Why Vingilótë does not have a generator). I was intrigued by Integrel Solutions (https://integrelsolutions.com/), an advanced power generation and control system, basically, super alternators with very high output, improving engine efficiency, and super smart controllers. At the time I thought their technology was too new and we went with the more or less industry standards Balmar alternators as second alternators. In our case their Series Six 70A 24Vdc alternator. Both failed a few days out of Cape Town, Vingilótë and her crew made it fine to Florida, with all around great support from Balance Catamarans, Nexus Yachts (who build the 526, 580, and 620 for Balance Catamarans, and Multi Marine (the marine electrician company that designed and installed all things electric and electronic on Vingilótë). In Florida Balmar investigated both alternators and concluded the rotors had been incorrectly by a (possibly disgruntled) employee in their last few weeks of employment. They repaired them overnight and installed them, all free of charge, and they worked without flaw since.
But in trying to debug why the alternators failed during the crossing to support the crew I did a lot of research on those alternators. In my opinion, the Balmar 70A/24Vdc alternators really aren’t well suited for the main power generation on marine diesels. They only produce power above 2,000rpms, they cut back their output to 60% when their temperature hits 100 degrees, which, because of the small frame form factor and lack of cooling air is very fast. On top of that the Balmar controllers do not support Lithium-Ion batteries well, if at all, and programming them is something a) out of the 1960s, b) you wouldn’t wish on your worst enemy, or c) not something you would want to do underway or even in less than ideal weather. Really, it’s d) all of the above.
A separate issue I discovered is that semi-custom catamarans like the Balance 526 systems change from boat to boat, and, with every system being unique, it is hard to get a system fully debugged and bring forward any improvements.
I went back to look at Integrel Solutions, talked a lot with Balance Catamarans, and out of that came the idea we could together design a power system that would work for everyone, no matter what usage they put on it where.
As we had a hand in designing it we wanted to a) not attach our name if we hadn’t thoroughly tested it ourselves and b) benefit from this awesome design. So we are currently reconfiguring Vingilótë to the ultimate power design for a catamaran and are taking her out for a three-day long weekend sailing.
Here is a video by Balance Catamarans on the Dream Team and the Dream Power Generation Solution: