I can’t really see much difference between your two different video cameras. Can you tape yourself crawling around figuring out the water ballast, please? And another thing I’m wondering: I think you are a smart and thoughtful guy and I think Bob is a smart and thoughtful guy. Why have you decided to go with a hydrogenerator while Bob has decided to go with solar panels?
The main difference is that the field of view is wider in the second one.
I'm not sure what drove Bob's decision process. Mine was both informed and opportunistic. There are many ways to go about this. For me, it is about redundancy. In other words, having multiple options to charge the batteries, regardless of conditions, and failure of course. So there was always going to be a combination of multiple systems: fuel/engine/alternator, solar, wind turbine, hydrogenerator.
We just happened to come across a "used" hydrogenerator (thanks Dave!). Then Rob T (thanks!) helped secure a second used one. I also have 275 Watts of solar panels. And the alternator is 115 Amps. So, the plan is an hydrogenerator for each tack. If one fails I can always swap. If both fail maybe I can scavenge parts from each and still have one working. I'm not sure what I'll do with the solar panels in terms of keeping them mobile or installing permanently (unlikely).
I don't have an electricity budget of my own. In Andrew Evans' book, Michael Hennessy says that his budget is 200 Amps/day for his Class40, or 8 1/3 Amps/ hr. I use that as my basis, untill I come down with a personalized budget. A 300 Watt hydrogenerator generates 8 Amps at 5 kts and it goes up from there. So that's right on the money. At 8 kts it's about twice that.
Now, unlike solar panels, hydrogenerators are quite demanding on a boat like Changabang. One needs to swap the propeller to match conditions. Then if inactive it needs to be secured up. They're in a place that's not exactly practical. The manufacturer also recommends a maintenance every 10,000 miles. They may take a good amount of beating with all the bouncing/banging that Changabang does upwind. Or a big breaking wave on the stern could take both of them away.
If the hydrogenerators work then I'm golden as long as I manage to avoid burning the converter (which is what stopped Joe Harris' attempt and he stopped for the first time in South Africa). If they both fail then I'm down to the solar panels/engine. Let's say that a worst case scenario on the solar panels is 50% efficiency for 6 hours and nothing else during the day/night. So that's about 55 Amps, maybe? I'd have to turn a lot of stuff off ... I can supplement with the engine. I think it burns 1/2 gallon per hour, which may give me about 75 Amps? My fuel tank is about 10.5 gallons. There are a bunch of jerry cans, to allow for a refill. So I have about 40 hours of charging with the engine.
A good battery monitor would help with all this exercise. There's one on Changabang but we think it may have gone South. It's still all a puzzle
