Test Sail

While last week was day after day of beautiful weather, the weekend is not. We had a storm system sitting on top of us, not moving at all. No working outside on Saturday, so it was a good day to catch up.

Last month we went out for a test sail and the sailing part of that went great. The boat did everything it was supposed to do. The sails are in great shape, the lines ran freely and the standing rigging stood strong. The problem we found was our electrical system was not up to the task of supporting live aboards. We have two sets of batteries – house batteries and engine starter batteries. Everything in the boat runs off the house batteries; water pumps, lights, refrigeration, fans, computers, tablets, phones and navigation equipment all run off the batteries. We have replaced almost every light on the boat with LED lights to reduce our power demand, but the house batteries still could not keep up. After that weekend, job #1 was beefing up our electrical system.

Here’s the math for our house batteries. We had four 225 amp hour 6V golf cart batteries. Two of these batteries in series make up one giant 225 amp hour 12V battery, so we basically had two big 12V batteries in parallel giving us a total of 450 amp hours at 12V. However, you need to be careful to not use too much of the battery’s charge. If you use over 50% it reduces the life of the batteries. That reduces our total usable capacity to 225 amp hours. Since we were just out for a weekend, the batteries were fully charged and we had access to the full 225 amp hours. When cruising the batteries rarely reach full charge; typically they only reach about 80%. That means that with a 450 amp hour battery bank you usually get about 135 amp hours of useful service from the batteries. Our refrigerator uses about 1 amp per hour or 24 amp hours per day. The pumps use about 5 amps, but they only run for about a minute at a time. LED lights use fractions of an amp. Compared to incandescent light using several amps that is a huge savings. Anyway, we should have had access to 225 amp hours and that should have been plenty, but the batteries were getting old and they could no longer hold that much charge.

The engine starter batteries. These are used for one thing and one things only and that is to start up our big, old diesel engine. There are two batteries that are just like car batteries. They are designed to deliver a lot of current for a short amount of time. They start the engine then get recharged from the alternator while the engine is running. Those batteries are doing well for now, so no need to change them out.

Anchored out for the night.

Our night out went well. Our new anchor held us in place, Wendy used our new stove to cook up a delicious meal, we ate dinner in the cockpit and watched dolphins swim around the boat. Everything electrical ran just fine. In the morning we could see that the battery voltage had dropped. That wasn’t good. We prepared to start the engine and while it did turn over, it turned over slow. It wasn’t able to start, so we switched from starter batteries to all batteries. That gave us a boost, but it was a cold morning (for FL) and the engine still didn’t catch. After a couple of tries the batteries quickly lost their charge, so we let them rest. We have solar panels and we had a sunny morning, so we let the panels slowly charge up the batteries. We also have a gas generator that we could use, but didn’t need to. After about 15 minutes the batteries had enough charge to try again and this time the engine started. That was a lot more trouble than it should have been and showed us that our batteries need replacing. After testing the batteries it appeared that our house batteries were weak and we used some of our engine batteries for house power. That weakened the engine batteries and made it more difficult to start the engine in the morning.

A truck battery might weigh 40 pounds, a small car battery only about 25 pounds. Our old house batteries weighed 65 pounds each. I had to pull each of those out and carry them off a floating boat while stepping over and around several obstacles. That was tough, but doable. When I went to buy the new batteries, the guy suggested larger 245 amp hour batteries. They had the same footprint as our old ones and were just ¾ inch taller with about 10% more storage capacity. That sounded like a good deal until I realized the batteries were 75 pounds each. It turns out that about 65 pounds is my limit for lifting something with one hand. 75 pounds required two hands. That made everything more difficult and it took a lot more effort to get the new batteries in than it took to get the old ones out. The next morning I felt like I had been hit by a car. Everything hurt. I need to add deadlifts to my workout routine.

New house batteries installed, we needed a way to keep them charged. If I wasn’t working, we probably wouldn’t have bothered, but with the energy demands of running a computer, phone and internet connection all day, every day, we decided to put in new solar panels. Our solar panels were only about 12 years old, but solar has changed a lot over that time. The new panels have twice the power for the same size and cost about half as much. Our old panels could produce as much as 230 watts in peak conditions, but replacing them with slightly smaller new panels we increased our charging capacity to 460 watts. That boils down to about 135 amp hours per day in peak conditions. That should be enough to keep the batteries charged. If we have a lot of cloudy days we can run the engine or use the gas generator. We want to install a wind generator, too. Unfortunately, that takes time that I don’t have, so it will have to wait.

We are working to get out of here in the next two weeks. The boat is nearly ready then we just need to get rid of a few more things, like some scuba equipment and our cars. We really want to get over to the Bahamas this month then work our way down to the Virgin Islands in April. Hopefully, my job doesn’t get in the way and in the next few weeks we can sail the boat over to where there is warm, blue water and white sand beaches.