ELECTRIC PROPULSION: SOME THOUGHTS ON ELECTRO SAILING: Part Two

Now that I've shown an example of how I am able to easily Electro-Sail with BIANKA when the winds fail to show up. I'll discuss the components that enable me to achieve it and some of the things I have learned in the past nine years since I converted BIANKA to Electric Propulsion.

My Thoosa 9000 EP system specifications were designed  for 20 miles at 4 knots. This was using my 8A4D AGM batteries only. I have never checked if this was the actual case nor do I want to unless it becomes necessary. BIANKA is a sailboat and I always prefer to use the sail for propulsion. Another reason to avoid trying to push the battery bank close to depletion is you decrease the amount charge cycles of the battery bank. As this chart below shows:

It's about saving the amps champs! But, that does not mean I just use the EP system to get into and out of the harbor. Which is very easy for an EP system to do. I tend to leave my home harbor for other destinations not just day sails. But, EP makes that easy to do too.

So what do I use when I feel the need to Electro Sail? I will first start out under battery power alone. I watch the XBM battery monitor to see when my battery back has dropped down to about 75% battery capacity from the 100% fully charged condition I started out with. This is about two hours after I have started motoring. As noted above this habit allows me to have more recharge cycles out of the battery over it's lifetime. This is better than depleting the bank to down say 50%. It also reduces the amount of time spent to charge the battery back up to 100%

So when the battery bank has dropped to the 75% capacity.  I fire up the Honda 2000i generator and plug in the ZIVAN NG-1 charger into it.

The ZIVAN has turned into a real workhorse and has been very reliable. When I first installed the Thoosa system back in 2008 I was concerned about what would happen if the charger went bad and could no longer charge the battery bank while on a cruise. So I bought a backup NG-1. I'm happy to say that the backup has remained in it's box for these past nine years and has never had to be put into service.  The ZIVAN also works well with the Honda 2000 generator. When I use it for Electro Sailing on BIANKA it functions as a power supply pushing out 15 amps of max current to propel the boat acting as a power supply to push the boat along. It's output is just 900 watts well within the maximum 1600 watts continuous rating of the Honda generator. As the graph below from one of my harbor tests shows that 900 watts allows me to motor BIANKA at around three knots without drawing any amps out of the battery bank:

 In fact it allows me to operated the Honda Generator in ECO mode which makes the one gallon of gas in the Honda generator last for about four hours. I have operated the ZIVAN in this full out mode for hours at a time without issue. BIANKA will move along quite nicely at this speed until the fuel runs out. Of course despite being a fairly sophisticated charger the ZIVAN does not know it is being used only has a power supply to push BIANKA along on a windless day. It thinks it is still charging a battery bank. Which brings up something one has to be on the lookout for when Electro-Sailing with this and other chargers. Because the charger never sees the battery being charged at some point it will disconnect. Thinking the battery is not charging it will timeout. It takes several hours to reach this conclusion and it is easily reset by unplugging it from the generator and plugging it back in. Then it is good to go for another several hours.
 One of the nice things about having Electric Propulsion is how easily it is to modify components of the system or change operating modes. Because the ZIVAN's output is limited to 900 watts it means I am not able to take advantage of the full 1600 watts continuous output of the Honda 2000i. So I am contemplating buying a 48 volt 1500 watt power supply to use when it looks like I will have to operate on an extended Electro-Sail mode. I expect it should move BIANKA along about 4 knots. I'll test and post about that hopefully some this upcoming season.

OH WELL!: Not all ideas work out.

Having Electric Propulsion can be boring. Once installed there is not a lot of maintenance or repair. But, it is easy to modify. So one day I thought about how when using the propulsion system  in hybrid mode on a windless day I am only using 900 watts of power from the Honda 2000i generator. That is because this is the max that the ZIVAN NG-1 charger can provide to the 48 volt battery bank. So I thought if I bought an additional 600 watt power supply and connected it in parallel with the Zivan I might be able to get another 12 amps when electro sailing. So yesterday I installed the wiring to make this happen and did some tests to see if my idea would work. Let's just say it did not. The Zivan performed as usual but, the new 600 watt power supply did not add any amps for charging like I thought. Oh well. I have not totally given up on the concept. I'll try another test and see if I can make it happen but, the first attempt was not encouraging. But, at least nothing smoked either. I'll post about the next attempt in the future.

NOTES OF AN ELECTRIC SAILOR: Late summer cruise 2013

I decided to head out on a late summer/early fall cruise yesterday. Before I did I topped up the 48 volt propulsion bank for the Thoosa 9000 system using the Honda 2000i generator at the mooring. In the morning I used the helm instrumentation panel to read the battery voltages here were the readings:

BATTERY 1   13.3 VOLTS

BATTERY 2   13.1 VOLTS

BATTERY 3   13.1 VOLTS

BATTERY 4   12.8 VOLTS 

PACK VOLTAGE 53.2 VOLTS

I left later than I had planned and so had to buck some current while heading out of the harbor. Once I got out to open water I found the winds were light to nonexistent for most of the day. So I motor sailed for most of the eight hours in the light breeze drawing currents from 5 amps to 25 amps. After a trip of 18 miles I picked up a mooring in a nearby harbor and took the following readings of the batteries on the instrumentation panel:

BATTERY 1   12.6 VOLTS

BATTERY 2   12.5 VOLTS

BATTERY 3   12.4 VOLTS

BATTERY 4   12.4 VOLTS

PACK VOLTAGE 50.7 VOLTS 

The percent charge as read on the Xantrex XBM battery monitor showed a reading of 83%. I fired up the Honda 2000i generator using the 900 watt ZIVAN NG-1 battery charger until it reached the second stage of charging. I then switched to the Dual Pro 4 charger which topped up each battery individually until fully charged. It took three and a half hours to fully recharge the propulsion bank. During which time I also charged the battery for the 12 volt house bank and the Electric Paddle outboard.


BLOG UPDATE:  I was relaxing in the cockpit enjoying a glass of wine when I suddenly realized that I never took the Amp Hour readings off of the XBM battery monitor after I finished the sail. After six years I guess I'm just too comfortable with the electric propulsion system to keep an eye on all the parameters. :)  Perhaps I'll remember next time.

LESSON LEARNED: Fear and Panic in East Hampton

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"I understand that fear is my friend, but not always. Never turn your back on fear. It should always be in front of you, like a thing that might have to be killed."-Hunter S.Thompson

I was thinking about a situation that occurred last year after I rode out Hurricane Earl in East Hampton's Three Mile Harbor . A few days later I decided to leave and head back to BIANKA's home port before the winds shifted in a few days. Looking at the Eldridge Tide and Pilot  book I knew I would have to get an early start to make sure I would make it through Plum Gut with a favoring current. So I awoke at 3:45 am and got ready to head out.  Normally I would start my Honda 2000 generator to power the 12 volt  battery charger. This helps lighten the load on the 12 volt battery bank when using the electric windlass. But, since it was the middle of the night and I did not want to disturb the other boats around me I just used the battery bank and windlass alone to raise the anchor.  After that was done I silently used my electric propulsion system to move the boat to the channel that lead to Gardiners Bay. When I was in the channel I fired up the Honda and  plugged in the 48 volt Zivan charger for the propulsion bank. I watched as the lights  came on that told me it was putting out some amps into the bank. I then turned on my Pro Mariner 12 volt 30 amp charger to help replenish the amps lost from raising the anchor. Everything was fine for a few minutes when all of a sudden I heard the Honda sputter and then rev just a little, It was still running but, I glanced at the indicator light for the 48 volt Zivan charger and it was out. Panic spread over me. I though the charger had died or at the very least a fuse had blown inside. What should I do? Do I continue in the hope that I don't need the charger to help provide the extra power for the propulsion bank. I do have a back up charger that I can use to charge the bank but, it can't be used  to help propel the bank like the ZIVAN NG-1 can. Do I turn around and go back and anchor to work on the problem? If I do I will probably miss the favoring current at Plum Gut.  I had a few fearful moments as I pondered what I should do.  I hated the idea of missing the current at Plum Gut because it might mean I would have to wait out several days until the wind shifted again. On the other hand having a fully operational auxiliary propulsion system was important too and since I was sailing alone it would be hard to work on it while underway. It turns out that my initial fears were entirely misplaced. There was nothing wrong with the 48 volt Zivan Power supply at all. In fact all systems were working fine. It took me a few minutes after my initial panic to figure out what had happened. What had actually happened is the circuit breaker on the Honda Generator had tripped. When that happens the generator does not stop running. The breaker just trips and stops supply power to the outlets. So in my mind when I heard the generator still running and saw that the lights for the 48 volt Zivan power supply were out I assumed there was something wrong with the charger. But, why did the breaker trip? Because I only used battery power to the windlass when raising the anchor I had drawn down the 12 volt battery bank a little more than usual. So when I was using the generator to charge that bank and then also plugged in the 48 volt Zivan charger it was too much current draw for the generator so the breaker tripped. The solution was to reset the breaker and just either charge the 12 volt bank or use the 48 volt Zivan charger but, not both. Which is what I did and happily I made it through Plum Gut before the current change and learned a lesson once again about not panicking when something goes wrong because it may not be as bad as you first think it is.
 

 "Everthings gonna be alright."- Bob Marley
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